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10-01-18 PC - APP B - PRELIMINARY WATER QUALITY MANAGEMENT PLAN ASMBLD
Appendix B: Preliminary Water Quality Management Plan (WQMP) THIS PAGE INTENTIONALLY LEFT BLANK PRELIMINARY WATER QUALITY MANAGEMENT PLAN (WQMP) TENTATIVE TRACT No. 17847 Orange, California Prepared For MILAN CAPITAL MANAGEMENT, INC 888 South Disneyland Drive, Suite 101 Anaheim, CA 92802 Prepared By Fuscoe Engineering, Inc. 16795 Von Karman, Suite 100 Irvine, California 92606 949.474.1960 www.fuscoe.com Project Manager: Dino Capannelli, PE Date Prepared: August 1, 2018 Job Number: 881.003.01 F:\Projects\881\003\_Support Files\Reports\WQMP\881-003rp_MaraBrandmanPWQMP_2018-08-01.pdf PRELIMINARY WATER QUALITY MANAGEMENT PLAN (WQMP) TENTATIVE TRACT NO. 17847 Santiago Canyon Road & Nicky Way Orange, CA 92869 COORDINATES: 33.813209, -117.787626 APN 379-451-24 Prepared for: MILAN CAPITAL MANAGEMENT, INC. 888 Disneyland Drive, Suite 101 Anaheim, CA 92802 714.687.1900 Prepared by: FUSCOE ENGINEERING, INC. 16795 Von Karman, Suite 100 Irvine, CA 92618 949.474.1960 Dino Capannelli, PE Date Prepared: August 1, 2018 Date Revised: Public Works Director Date City Engineer Date P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 MILAN CAPITAL MANAGEMENT, INC. i OWNER’S CERTIFICATION PROJECT OWNER’S CERTIFICATION Permit/Application No.: Grading Permit No.: Tract/Parcel Map and Lot(s)No.: TTM 17847 Building Permit No.: Address of Project Site and APN: Santiago Canyon Road & Nicky Way, Orange, California 92869 APN: 379-451-24 COORDINATES: 33.813209, -117.787626 This Preliminary Water Quality Management Plan (WQMP) has been prepared for MILAN CAPITAL MANAGEMENT, INC. by FUSCOE ENGINEERING, INC. The WQMP is intended to comply with the requirements of the City of Orange Site Plan No. requiring the preparation of the plan. The undersigned, while it owns the subject property, is responsible for the implementation of the provisions of this plan and will ensure that this plan is amended as appropriate to reflect up-to-date conditions on the site consistent with the City of Orange Local Implementation Plan (LIP), and the intent of NPDES Permit and Waste Discharge Requirements for the City of Orange, County of Orange, Orange County Flood Control District and the incorporated Cities of Orange County within the Santa Ana Region. This WQMP will be reviewed with the facility operator, facility supervisors, employees, tenants, maintenance and service contractors, or any other party having responsibility for implementing portions of this WQMP. Maintenance requirements within Section V and Appendix D will be adhered to with particular emphasis on maintaining the BMPs described within Sections IV and V. The Owner’s Annual Self Certification Statement along with a BMP maintenance implementation table will be submitted by June 30th every year following project completion. At least one copy of the approved WQMP shall be available on the subject property in perpetuity. Once the undersigned transfers its interest in the property, its successors-in-interest shall bear the aforementioned responsibility to implement and amend the WQMP. The City of Orange will be notified of the change of ownership and the new owner will submit a new certification. Signature: Date: Name: Title: Company: Address: Email: Telephone #: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 MILAN CAPITAL MANAGEMENT, INC. ii OWNER’S CERTIFICATION NOTICE OF TRANSFER OF RESPONSIBILITY Water Quality Management Plan WQMP Number – As assigned by the City of Orange: Submission of this Notice of Transfer of Responsibility constitutes notice to the City that responsibility for the Water Quality Management Plan (WQMP) for the subject property identified below, and implementation of that plan, is being transferred from the Previous Owner (and his/her agent) of the site (or portion thereof) to the New Owner, as further described below. I. Previous Owner/ Responsible Party Information Company/ Individual: Contact Person: Street Address: Title: City: State: Zip: Phone: II. Information about Site Relevant to WQMP Name of Project: Title of WQMP applicable to site: Street Address of the site: Date of Transfer of Responsibility: III. New Owner/ Responsible Party Information Company/ Individual: Contact Person: Street Address: Title: City State Zip Phone: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. iii TABLE OF CONTENTS TABLE OF CONTENTS SECTION I DISCRETIONARY PERMITS AND WATER QUALITY CONDITIONS ............................ 1 SECTION II PROJECT DESCRIPTION ...................................................................................... 2 II.1 Project Description ....................................................................................................... 2 II.2 Project Purpose and Activities ........................................................................................ 3 II.3 Potential Storm Water Pollutants .................................................................................... 3 II.4 Hydrologic Conditions of Concern ................................................................................. 5 II.5 Post Development Drainage Characteristics .................................................................... 7 II.6 Residential Projects ....................................................................................................... 7 II.7 Property Ownership/Management ................................................................................. 7 SECTION III SITE DESCRIPTION .......................................................................................... 8 III.1 Physical Setting ............................................................................................................ 8 III.2 Site Characteristics ....................................................................................................... 8 III.3 Watershed Description................................................................................................ 10 SECTION IV BEST MANAGEMENT PRACTICES (BMPs) ......................................................... 11 IV.1 Site Design BMPs ....................................................................................................... 12 IV.2 Source Control BMPs ................................................................................................. 14 IV.2.1 Non-Structural Source Control BMPs..................................................................... 14 IV.2.2 Structural Source Control BMPs ............................................................................ 16 IV.3 Low Impact Development BMP Selection ...................................................................... 17 IV.3.1 Hydrologic Source Controls (HSCs) ....................................................................... 17 IV.3.2 Infiltration BMPs .................................................................................................. 19 IV.3.3 Evapotranspiration & Rainwater Harvesting BMPs ................................................... 21 IV.3.4 Biotreatment BMPs .............................................................................................. 22 IV.3.5 Hydromodification Control BMPs .......................................................................... 23 IV.3.6 Regional/Sub-Regional LID BMPs ......................................................................... 24 IV.3.7 Treatment Control BMPs ...................................................................................... 24 IV.4 Water Quality Credits ................................................................................................. 24 IV.5 Alternative Compliance Plan Information ...................................................................... 24 IV.6 Vector Control ........................................................................................................... 24 IV.7 Drainage Management Areas ..................................................................................... 24 IV.8 Calculations .............................................................................................................. 26 IV.8.1 Design Capture Volume (DCV) ............................................................................. 26 IV.8.2 Bioretention Without Underdrains BMP Design (Capture Efficiency Method) .............. 35 P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. iv TABLE OF CONTENTS IV.8.3 Modular Wetland System BMP Design ................................................................... 38 SECTION V IMPLEMENTATION, MAINTENANCE & INSPECTION RESPONSIBILITY FOR BMPs (O&M PLAN) .................................................................................................................... 41 V.1 Frequency Inspection Matrix ........................................................................................ 42 V.2 Regulatory Permits ...................................................................................................... 46 V.3 Funding .................................................................................................................... 46 V.4 Owner Self-Certification Statement .............................................................................. 47 V.5 BMP Implementation Tracking ..................................................................................... 48 SECTION VI LOCATION MAP, SITE PLAN AND BMP DETAILS ............................................... 49 SECTION VII EDUCATIONAL MATERIALS ............................................................................ 53 APPENDICES ......................................................................................................................... 54 APPENDICES Appendix A .................................. Conditions of Approval, Resolution Number______ dated _______ Appendix B ................................................................................................... Educational Materials Appendix C ................................................................................................................ BMP Details Appendix D ................................................................... BMP Maintenance Information / O&M Plan Appendix E ....................................................................... Infiltration Testing & Geotechnical Report Appendix F .................................. Hydrology Information (Q2 – Two-year frequency storm evaluation) LIST OF TABLES Table 1. Site Design BMPs ....................................................................................................... 13 Table 2. Non-Structural Source Control BMPs ........................................................................... 14 Table 3. Structural Source Control BMPs ................................................................................... 16 Table 4. Hydrologic Source Control BMPs ................................................................................. 18 Table 5. Infiltration BMPs ......................................................................................................... 19 Table 6. Evapotranspiration, Rainwater Harvesting ..................................................................... 21 Table 7. Biotreatment BMPs ..................................................................................................... 22 P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 1 DISCRETIONARY PERMITS & WATER QUALITY CONDITIONS SECTION I DISCRETIONARY PERMITS AND WATER QUALITY CONDITIONS PROJECT INFORMATION Permit/Application No.: Grading or Building Permit No.: Address of Project Site (or Tract Map and Lot Number if no address) and APN: Santiago Canyon Road & Nicky Way, Orange, California 92869 APN: 379-451-24 COORDINATES: 33.813209, -117.787626 WATER QUALITY CONDITIONS OF APPROVAL OR ISSUANCE Discretionary Permit(s): Pending – to be provided in Final WQMP Water Quality Conditions of Approval or Issuance applied to this project: (Please list verbatim.) Pending Issuance - To be provided in Appendix A of the Final WQMP upon issuance by the City of Orange. Water Quality Conditions of Approval (COA) are copied from full project COAs (Appendix A) and included here in the Final WQMP. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 2 PROJECT DESCRIPTION SECTION II PROJECT DESCRIPTION II.1 PROJECT DESCRIPTION The proposed Tentative Tract No. 17847 (formerly known as the Mara Brandman Arena Site) project site encompasses approximately 7.44 acres in the City of Orange. The project site is bounded by East Santiago Canyon Road to the north, Orange Park Boulevard to the east, and Nicky Way to the south and west. A Vicinity Map is included in Section VI. The table below summarizes the proposed project. DESCRIPTION OF PROPOSED PROJECT Planning Area/ Community Name: Not applicable. Project Area (ft2): 7.44 ft2 (323,794 acres) # of Dwelling Units: 6 undeveloped, rough graded residential lots SIC Code: Not applicable Narrative Project Description: The proposed 7.44-acre redevelopment project plans to rough grade 6 single-family residential estate lots of approximately 1.0 to 1.3 acres in size for future development or sale. No buildings, or structures will be developed on the rough graded pads as a part of this project. They will remain vacant lots upon completion. The project will also include a public street as well as additional public street improvements to Nicky Way. The proposed improvements to Nicky Way are to widen the existing street and to include the extension of an equestrian trail. Biofiltration BMPs are proposed within the proposed public streets and Nicky Way street improvements. Development of BMPs for both public right-of-ways followed the guidelines from US EPA’s Green Streets Manual, found in Appendix B of the 2013 Model WQMP for North Orange County. The proposed BMPs are discussed further in Section IV.3 of this WQMP. Project Area: Pervious Area Pervious Area Percentage Impervious Area Impervious Area Percentage Pre-Project Conditions: 6.70 ac 90% 0.74 ac 10% Post-Project Conditions: 3.72 ac 50% 3.72 ac 50% Drainage Patterns/ Connections: Under existing conditions, water runoff from Nicky Way drains to grate inlets found along Nicky Way. Runoff then continues from the grate inlet to the public storm drain line that connects to the Santiago Creek Channel located north of the project site. Runoff from Santiago Canyon Road drains in a westerly direction along the street before draining directly into the Santiago P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 3 PROJECT DESCRIPTION DESCRIPTION OF PROPOSED PROJECT Creek Channel. All runoff into Santiago Creek discharges to the Santa Ana River and ultimately the Pacific Ocean at Huntington Beach. Under proposed conditions, runoff will be conveyed in a manner similar to existing conditions. Each of the proposed lots will be graded to drain towards the center of the site and the proposed public street. Low-flows and first-flush runoff from each of the lots will be intercepted by on-lot infiltration BMPs. Flows from the public street will drain westerly and to one of two Modular Wetland Units for treatment prior to discharging into the existing storm drain along Nicky Way. Runoff then flows northerly and outlets to the Santiago Creek Channel. II.2 PROJECT PURPOSE AND ACTIVITIES The purpose of the project is to rough grade the project site for future sale or development of the resulting 6 residential estate lots. No activities are proposed for the project site. No buildings are proposed as a part of this development. II.3 POTENTIAL STORM WATER POLLUTANTS The table below, derived from Table 2 of the Countywide Model WQMP Technical Guidance Document (revised December 2013), summarizes the categories of land use or project features of concern and the general pollutant categories associated with them. Priority Project Categories and/or Features: Streets, Highways, & Freeways. Detached Residential Development (to be developed in the future or by others). POLLUTANTS OF CONCERN Pollutant E = Expected to be of concern N =Not Expected to be of concern Additional Information and Comments Suspended Solid/ Sediment E Nutrients E Heavy Metals E Pathogens (Bacteria/Virus) E 303(d) listed impairment (Santa Ana River, Reach 2) Pesticides E Oil & Grease E P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 4 PROJECT DESCRIPTION POLLUTANTS OF CONCERN Pollutant E = Expected to be of concern N =Not Expected to be of concern Additional Information and Comments Toxic Organic Compounds E Trash & Debris E There are no GeoTracker-listed cleanup sites within the vicinity of the project site. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 5 PROJECT DESCRIPTION II.4 HYDROLOGIC CONDITIONS OF CONCERN The purpose of this section is to identify any hydrologic conditions of concern (HCOC) with respect to downstream flooding, erosion potential of natural channels downstream, impacts of increased flows on natural habitat, etc. As specified in Section 2.3.3 of the 2011 Model WQMP, projects must identify and mitigate any HCOCs. A HCOC is a combination of upland hydrologic conditions and stream biological and physical conditions that presents a condition of concern for physical and/or biological degradation of streams. In the North Orange County permit area, HCOCs are considered to exist if any streams located downstream from the project are determined to be potentially susceptible to hydromodification impacts and either of the following conditions exists: Post-development runoff volume for the 2-yr, 24-hr storm exceeds the pre-development runoff volume for the 2-yr, 24-hr storm by more than 5 percent or Time of concentration (Tc) of post-development runoff for the 2-yr, 24-hr storm event exceeds the time of concentration of the pre-development condition for the 2-yr, 24-hr storm event by more than 5 percent. If these conditions do not exist or streams are not potentially susceptible to hydromodification impacts, an HCOC does not exist and hydromodification does not need to be considered further. In the North Orange County permit area, downstream channels are considered not susceptible to hydromodification, and therefore do not have the potential for a HCOC, if all downstream conveyance channels that will receive runoff from the project are engineered, hardened, and regularly maintained to ensure design flow capacity, and no sensitive habitat areas will be affected. Is the proposed project potentially susceptible to hydromodification impacts? Yes No (show map) A preliminary hydromodification analysis was prepared for the ultimate condition of the project site. However, this condition is not representative of the proposed project since the rough graded residential lots will remain vacant and undeveloped, where hydromodification impacts will not exist. Removal of the existing paved parking lot will, in fact, reduce post-development runoff conditions from pre- development conditions in the interim. The purpose of this analysis is to provide full disclosure of the ultimate build-out condition for the future development or sale of the property. The project site is a part of the Santiago Creek watershed, which is a major tributary of the Santa Ana River. Handy Creek, which the project site runoff discharges into, is an underground box culvert underneath Nicky Way. Handy Creek conveys site runoff to Santiago Creek, north of the project site. Santiago Creek confluences with Santa Ana River downstream and ultimately discharges into the Pacific Ocean. Santiago Creek Channel (E08) is considered hydromodification susceptible (see screenshot below). P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 6 PROJECT DESCRIPTION Figure XVI-3c Susceptibility Analysis Santa Ana River 2-YEAR, 24-HOUR STORM SUMMARY Condition Tc Peak Runoff Volume Pre-development 17.53 min 6.64 cfs 0.59 ac-ft Proposed 17.17 min 7.05 cfs 0.70 ac-ft Difference – 0.36 min +0.38 cfs +0.11 ac-ft % Change – 2% +5.7% +18.6% The results of the 2-year hydrology analysis found that implementation of the proposed project in its ultimate build-out condition would result in an increase in overall volume of flows discharged from the site (see Appendix F). Since the increase is greater than 5%, it represents a potential HCOC, and would require on-site retention to mitigate the impact. Retention of the excess volume of approximately 0.11 acre-feet (4,792 ft3) will be achieved through the implementation of LID BMPs, since the DCV exceeds this hydromodification volume (see Section IV for details). This will be accomplished in a future phase of development and separate WQMP(s), since HCOCs will not exist for this current project. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 7 PROJECT DESCRIPTION II.5 POST DEVELOPMENT DRAINAGE CHARACTERISTICS Under proposed conditions, runoff will be conveyed in a manner similar to existing conditions. Each of the proposed lots will be graded to drain towards the center of the site and the proposed public street. Low-flows and first-flush runoff from each of the lots will be intercepted by on-lot infiltration BMPs. Flows from the public street will drain westerly and to one of two Modular Wetland Units for treatment prior to discharging into the existing storm drain along Nicky Way. Runoff then flows northerly and outlets to the Santiago Creek Channel. II.6 RESIDENTIAL PROJECTS The proposed residential estate lots will remain as rough graded pads for future development or sale, ranging from 1.0 acres to 1.2 acres in size. No buildings, pools, parking lots, landscaped areas, or any structures are proposed as part of this development. These details will be provided in a future, separate WQMP(s) as part of their subsequent development. II.7 PROPERTY OWNERSHIP/MANAGEMENT PROPERTY OWNERSHIP/MANAGEMENT Public Streets: City of Orange Open Space: Milan Capital Management, Inc. Estate Lots: Milan Capital Management, Inc. Equestrian Trail: City of Orange Structural BMPs: On-lot BMPs: Milan Capital Management, Inc., Individual Homeowners Public Right-of-Way BMPs: City of Orange The Owner, Milan Capital Management, Inc. shall assume all BMP maintenance and inspection responsibilities for the six proposed residential estate lots. The City of Orange shall assume all maintenance and inspection responsibilities for BMPs within the City right-of-way. Inspection and maintenance responsibilities are outlined in Section V of this report. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 8 SITE DESCRIPTION SECTION III SITE DESCRIPTION III.1 PHYSICAL SETTING Reference Location Map: 33.813209, -117.787626 Site Address: SEC of Santiago Canyon Road and Nicky Way, Orange, CA 92869 Land Use: Estate Low Density Residential Zoning: R-1-40 (Single Family Residential, 40,000 ft2) Predominant Soil Type: Group A Impervious Conditions: Existing Impervious: 10% Proposed Impervious: 50% Pervious Conditions: Existing Pervious: 90% Proposed Pervious: 50% III.2 SITE CHARACTERISTICS Precipitation Zone: 0.85 inches per TGD Figure XVI-1 Site Description: Under existing conditions, the project site is occupied by an equestrian arena facility with an asphalt parking lot. A portion of the project site is also undeveloped and exists as a vacant dirt lot. Adjacent land uses include a quarry site to the north, the Salem Lutheran Church to the east, and residential neighborhoods to the south and west. Topography: The western portion of the project site is relatively flat and generally drains towards an existing low point and catch basin at the intersection of Nicky Way and Santiago Canyon Road. The eastern portion of the site contains steeper slopes (approx. 39% grade) that will be graded and flattened for the rough grading pads of the residential estate lots. Existing Drainage Patterns/ Connections: Under existing conditions, water runoff from Nicky Way drains to grate inlets found along Nicky Way. Runoff then continues from the grate inlet to the public storm drain line that connects to the Santiago Creek Channel located north of the project site. Runoff from Santiago Canyon Road drains in a westerly direction along the street before draining directly into the Santiago Creek Channel. All runoff into Santiago Creek discharges to the Santa Ana River and ultimately the Pacific Ocean at Huntington Beach. Soil Type, Geology, and Infiltration Properties: Based on a soils infiltration study performed by Ginter & Associates, Inc. in 2015, 5 boring holes were tested throughout the project site to depths of 5 feet. Infiltration rates in the western-most portions of the site were lower than those found in the central eastern portions of the site. The overall site was deemed to be feasible for infiltration, with an infiltration rate of 3-4 in/hr prior to application of a factor of safety. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 9 SITE DESCRIPTION Hydrogeologic (Groundwater) Conditions: Based on a geotechnical report conducted by Ginter & Associates, Inc. in 2011 for a site directly north and adjacent to the current project site, significant subterranean groundwater flows were present south of the Santiago Creek. The direction of subterranean flow is generally east to west and parallel to the Santiago Creek and found to be approximately 34-52 feet below ground surface. Geotechnical Conditions (relevant to infiltration)1: Infiltration is considered feasible for the project site, with an average rate of 2.4 inches per hour prior to application of a factor of safety. Off-Site Drainage: Runon onto the site will be minimal (drainage area of approx. 0.56 acres), originating from the slopes along the eastern portion of the project site. These slopes will remain natural, vegetated condition. Utility and Infrastructure Information: Handy Creek (Orange County Flood Control District), which the project site runoff discharges into, is an existing underground box culvert underneath Nicky Way. Handy Creek conveys site runoff to Santiago Creek, north of the project site. Watershed Management Priorities: Not applicable. 1 (Albus-Keefe & Associates, Inc., 2016) P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 10 SITE DESCRIPTION III.3 WATERSHED DESCRIPTION Watershed: Santiago Creek, Santa Ana River Watershed Downstream Receiving Waters: Handy Creek Santiago Creek Santa Ana River (Reach 2) Santa Ana River (Reach 1) 303(d) Listed Impairments: Santa Ana River Reach 2 — bacteria (2012 list) Applicable TMDLs: None Hydrologic Conditions of Concern (HCOCs): Refer to Section II.4 for details. Watershed Management Priorities: Not Applicable P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 11 BEST MANAGEMENT PRACTICES SECTION IV BEST MANAGEMENT PRACTICES (BMPs) Best Management Practices (BMPs) are programs and policies, including structural controls that are implemented to control the discharge of pollutants from the project site. This Section describes site design BMPs, source control BMPs, hydromodification control BMPs and treatment control BMPs. The proposed LID BMPs discussed in Section IV.3 have been selected for the project based on the feasibility criteria as defined in the 2011 Countywide Model WQMP and Technical Guidance Document (TGD)2,3, as well as the project’s Pollutants of Concern, the BMP’s ability to effectively treat those pollutants, specific site conditions (such as presence of low-infiltrating soil layers), setback requirements from building foundations, retaining wall footings and utilities. The proposed project is to rough grade 6 single-family residential estate lots of approximately 1.0 to 1.3 acres in size for future development or sale. Since infiltration was found to be feasible for the central and eastern portions of the site, the DMAs have been sized for the implementation of a bioretention without underdrain (INF-3) based on TGD methodology using a site-wide average infiltration rate in order to give full disclosure of the required build-out water quality conditions for these 6 lots and to demonstrate the potential scale and locations of infiltration BMPs. These BMPs are discussed further in Section IV.3.2 below. Development of BMPs for both public right-of-ways followed the guidelines from US EPA’s Green Streets Manual, found in Appendix B of the 2013 Model WQMP for North Orange County. The proposed BMPs are discussed further in the following sections. Consistent with the Model WQMP, the following performance criteria have been applied to the project. Is there an approved WIHMP or equivalent for the project area that includes more stringent LID feasibility criteria or if there are opportunities identified for implementing LID on regional or sub-regional basis? Yes No 2 County of Orange Planning Division. (2011, May 19). Exhibit 7.II Model Water Quality Management Plan (WQMP). 3 County of Orange Planning Division. (2013, December 20). Exhibit 7.III Technical Guidance Document (TGD) for the Preparation of Conceptual/Preliminary and/or Project Water Quality Management Plans (WQMPs). P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 12 BEST MANAGEMENT PRACTICES PROJECT PERFORMANCE CRITERIA Hydromodification Control Performance Criteria: (Model WQMP Section 7.II-2.4.2.2) If a hydrologic condition of concern (HCOC) exists, priority projects shall implement onsite or regional hydromodification controls such that: Post-development runoff volume for the two-year frequency storm does not exceed that of the predevelopment condition by more than five percent, and Time of concentration of post-development runoff for the two-year storm event is not less than that for the predevelopment condition by more than five percent. Where the Project WQMP documents that excess runoff volume from the two-year runoff event cannot feasibly be retained and where in-stream controls cannot be used to otherwise mitigate HCOCs, the project shall implement on-site or regional hydromodification controls to: Retain the excess volume from the two-year runoff event to the MEP, and Implement on-site or regional hydromodification controls such that the post-development runoff two-year peak flow rate is no greater than 110 percent of the predevelopment runoff two-year peak flow rate. LID Performance Criteria: (Model WQMP Section 7.II-2.4.3) Infiltrate, harvest and use, evapotranspire, or biotreat/biofilter, the 85th percentile, 24-hour storm event (Design Capture Volume). LID BMPs must be designed to retain, on-site, (infiltrate, harvest and use, or evapotranspire) storm water runoff up to 80 percent average annual capture efficiency. Treatment Control BMP Performance Criteria: (Model WQMP Section 7.II-3.2.2) If it is not feasible to meet LID performance criteria through retention and/or biotreatment provided on-site or at a sub-regional/regional scale, then treatment control BMPs shall be provided on-site or offsite prior to discharge to waters of the US. Sizing of treatment control BMP(s) shall be based on either the unmet volume after claiming applicable water quality credits, if appropriate. LID Design Storm Capture Volume: The Simple Method DCV without consideration to other factors (BMPs, hydromodification, etc.) for the TTM 17847 property (7.44 ac) is 12,040.6 cu-ft. Refer to Section IV.7 for specific Drainage Manage Area (DMA) breakdown and Section IV.8 for detailed calculations (Worksheet B). IV.1 SITE DESIGN BMPS The following table describes the site design BMPs used in this project and the methods used to incorporate them. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 13 BEST MANAGEMENT PRACTICES TABLE 1. SITE DESIGN BMPS TECHNIQUE INCLUDED? IF NO, STATE JUSTIFICATION YES NO Minimize Directly Connected Impervious Areas (DCIAs) (C-Factor Reduction) Create Reduced or “Zero Discharge” Areas (Runoff Volume Reduction)1 Minimize Impervious Area/Maximize Permeability (C-Factor Reduction)2 Conserve Natural Areas (C-Factor Reduction) The existing site does not have natural areas to protect. Notes: 1. Detention and retention areas incorporated into landscape design provide areas for retaining and detaining storm water flows, resulting in lower runoff rates and reductions in volume due to limited infiltration and evaporation. Such Site Design BMPs may reduce the size of Treatment Control BMPs. 2. The “C Factor” is a representation of the ability of a surface to produce runoff. Surfaces that produce higher volumes of runoff are represented by higher C Factors. By incorporating more pervious, lower C Factor surfaces into a development, lower volumes of runoff will be produced. Lower volumes and rates of runoff translate directly to lowering treatment requirements. Minimize Directly Connected Impervious Areas (DCIAs) (C-Factor Reduction) Landscaping will be provided throughout the site within the individual lots, along the trail easements and around the existing perimeter slopes to disconnect impervious areas. Create Reduced or “Zero Discharge” Areas (Runoff Volume Reduction) Runoff from the proposed lots will drain to bioretention facilities without underdrains to allow low flows & first-flush runoff to infiltrate into the subsoils. These features are discussed further in Section IV.3.2 below. Minimize Impervious Area/Maximize Permeability (C-Factor Reduction) Impervious surfaces have been minimized by incorporating landscaped areas throughout the site within the individual lots, and along the trail easements and perimeter slopes. Runoff form the proposed residential lots will drain to infiltration BMPs to maximize permeability. Conserve Natural Areas (C-Factor Reduction) There are no existing vegetated or sensitive areas to preserve on the project site. The project site will consist of the repaving of existing roadways, the construction of a new roadway, and grading for the 6 residential estate lots that will be left vacant until later development in the future. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 14 BEST MANAGEMENT PRACTICES IV.2 SOURCE CONTROL BMPS IV.2.1 Non-Structural Source Control BMPs The table below indicates all BMPs to be incorporated in the project. For those designated as not applicable (N/A), a brief explanation why is provided. TABLE 2. NON-STRUCTURAL SOURCE CONTROL BMPS ID Name Included? Not Applicable? If Not Applicable, Provide Brief Reason N1 Education for Property Owners, Tenants and Occupants Current phase of development will only consist of rough grading for residential lots, to be developed in the future. There will be no occupants following the immediate completion of the project. N2 Activity Restrictions Current phase of development will only consist of rough grading for residential lots, to be developed in the future. There will be no occupants following the immediate completion of the project. N3 Common Area Landscape Management N4 BMP Maintenance N5 Title 22 CCR Compliance (How development will comply) Not applicable, residential development N6 Local Water Quality Permit Compliance The City of Orange does not issue water quality permits. N7 Spill Contingency Plan Not applicable, no fueling on-site N8 Underground Storage Tank Compliance No Underground Storage tank is proposed N9 Hazardous Materials Disclosure Compliance No hazardous material sites are proposed N10 Uniform Fire Code Implementation Not applicable, no hazardous materials on-site. N11 Common Area Litter Control N12 Employee Training P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 15 BEST MANAGEMENT PRACTICES TABLE 2. NON-STRUCTURAL SOURCE CONTROL BMPS ID Name Included? Not Applicable? If Not Applicable, Provide Brief Reason N13 Housekeeping of Loading Docks No loading docks are proposed N14 Common Area Catch Basin Inspection N15 Street Sweeping Private Streets and Parking Lots N16 Retail Gasoline Outlets No retail gasoline outlets are proposed N3, Common Area Landscape Management Management programs will be designed and implemented by the Owner to maintain all the common areas within the project site. These programs will cover how to reduce the potential pollutant sources of fertilizer and pesticide uses, utilization of water-efficient landscaping practices and proper disposal of landscape wastes by the owner/developer and/or contractors. N4, BMP Maintenance The Owner will be responsible for the implementation and maintenance of each applicable non- structural BMP, as well as scheduling inspections and maintenance of all applicable structural BMP facilities through its staff, landscape contractor, and/or any other necessary maintenance contractors. Details on BMP maintenance are provided in Section V of this WQMP, and the O&M Plan is included in Section V and Appendix D. N11, Common Area Litter Control The Owner will be responsible for performing trash pickup and sweeping of littered common areas on a weekly basis or whenever necessary. Responsibilities will also include noting improper disposal materials by tenants. N12, Employee Training All employees of the Owner and any contractors will require training to ensure that employees are aware of activities that may result in pollutants reaching the storm drain. Training will include, but not be limited to, spill cleanup procedures, proper waste disposal, housekeeping practices, etc. N14, Common Area Catch Basin Inspection All on-site public catch basin inlets and drainage facilities shall be inspected and maintained by the City of Orange at least once a year, prior to the rainy season, no later than October 1st of each year. N15, Street Sweeping Private Streets and Parking Lots The City of Orange shall be responsible for sweeping all public streets within the project on a weekly basis. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 16 BEST MANAGEMENT PRACTICES IV.2.2 Structural Source Control BMPs The table below indicates all BMPs to be incorporated in the project. For those designated as not applicable (N/A), a brief explanation why is provided. TABLE 3. STRUCTURAL SOURCE CONTROL BMPS ID Name Included? Not Applicable? If Not Applicable, Provide Brief Reason S1 SD-13 Provide storm drain system stenciling and signage S2 SD-34 Design and construct outdoor material storage areas to reduce pollution introduction No outdoor storage areas are proposed. S3 SD-32 Design and construct trash and waste storage areas to reduce pollution introduction No outdoor trash enclosures are proposed. S4 SD-12 Use efficient irrigation systems & landscape design, water conservation, smart controllers, and source control S5 Protect slopes and channels and provide energy dissipation S6 SD-31 Properly Design: Dock areas No loading docks are proposed. S7 SD-31 Properly Design: Maintenance bays No maintenance bays are proposed. S8 SD-33 Properly Design: Vehicle wash areas No wash areas are proposed. S9 SD-36 Properly Design: Outdoor processing areas No processing areas are proposed. S10 Properly Design: Equipment wash areas No wash areas are proposed. S11 SD-30 Properly Design: Fueling areas No fueling areas are proposed. S12 SD-10 Properly Design: Hillside landscaping There are no slopes or channels on the project site. S13 Properly Design: Wash water control for food preparation areas No food preparation areas are proposed. S14 Properly Design: Community car wash racks No car wash racks are proposed. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 17 BEST MANAGEMENT PRACTICES S1/SD-13, Provide storm drain system stenciling and signage The phrase “NO DUMPING! DRAINS TO OCEAN” will be stenciled on all major storm drain inlets within the project site to alert the public to the destination of pollutants discharged into storm water. Stencils shall be in place prior to release of certificate of occupancy. Stencils shall be inspected for legibility on an annual basis and re-stenciled as necessary. S4/SD-12, Use efficient irrigation systems & landscape design, water conservation, smart controllers, and source control The Owner will be responsible for the installation and maintenance of all common landscape areas utilizing similar planting materials with similar water requirements to reduce excess irrigation runoff. The Owner will be responsible for implementing all efficient irrigation systems for common area landscaping including, but not limited to, provisions for water sensors and programmable irrigation cycles. This includes smart timers, rain sensors, and moisture shut-off valves. The irrigation systems shall be in conformance with City water efficiency guidelines. Systems shall be tested twice per year, and water used during testing/flushing shall not be discharged to the storm drain system. S5, Protect slopes and channels and provide energy dissipation The site drainage design shall include appropriate BMPs to decrease the potential for erosion of slopes. The design shall be consistent with Federal, State, and local standards (e.g., RWQCB, ACOE, CDFG). As applicable, the following principles shall be used: 1) convey runoff safely from the tops of slopes, 2) avoid disturbing steep or unstable slopes, as well as natural channels, 3) implement a permanent stabilization BMP on disturbed slopes and channels as quickly as possible, such as native vegetation, and 4) install energy dissipaters at the outlets of new storm drains, culverts, or channels. IV.3 LOW IMPACT DEVELOPMENT BMP SELECTION Low Impact Development (LID) BMPs are required in addition to site design measures and source controls to reduce pollutants in storm water discharges. LID BMPs are engineered facilities that are designed to retain or biotreat runoff on the project site. The 4th Term MS4 Storm Water Permit (Order R8-2009-0030) requires the evaluation and use of LID features using the following hierarchy of treatment: infiltration, evapotranspiration, harvest/reuse, and biotreatment. The following sections summarize the LID BMPs proposed for the project in accordance with the permit hierarchy and performance criteria outlined in Section IV.1. IV.3.1 Hydrologic Source Controls (HSCs) Hydrologic source controls (HSCs) can be considered to be a hybrid between site design practices and LID BMPs. HSCs are distinguished from site design BMPs in that they do not reduce the tributary area or reduce the imperviousness of a drainage area; rather they reduce the runoff volume that would result from a drainage area with a given imperviousness compared to what would result if HSCs were not used. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 18 BEST MANAGEMENT PRACTICES TABLE 4. HYDROLOGIC SOURCE CONTROL BMPS ID Name Included? HSC-1 Localized on-lot infiltration HSC-2 Impervious area dispersion (e.g. roof top disconnection) HSC-3 Street trees (canopy interception) HSC-4 Residential rain barrels (not actively managed) HSC-5 Green roofs/Brown roofs HSC-6 Blue roofs HSC-7 Impervious area reduction (e.g. permeable pavers, site design) Other: HSCs were not incorporated into the project’s design at this stage in the project’s development. Any HSC’s will be accounted for during final design of the residential estate lots and the cumulative volume of the HSC’s will be subtracted from the required treatment volume in a future, separate WQMP(s). Green Street / Linear Project BMPs Due to the inclusion of improvements to Nicky Way as part of the proposed project, the Project will incorporate United States Environmental Protection Agency (USEPA) guidance, “Managing Wet Weather with Green Infrastructure: Green Streets” as described in the Model WQMP Appendix B, in a manner consistent with the maximum extent practicable (MEP) standard. This approach includes: Selecting LID BMPs that integrate with both the opportunities and constraints of the project site and to attempt to address pollutants of concern and HCOCs, Developing innovative stormwater management configurations integrating “green” with “grey” infrastructure, Sizing BMPs opportunistically to provide stormwater pollution reduction to the MEP, accounting for the many competing considerations in right of ways. This only applies to the proposed public streets and street improvements along Nicky Way. The standard LID hierarchy described in Section 7.II-2.4.3 of the Model WQMP is not applicable to this portion of the project and is replaced by considering all feasible LID approaches listed in the Green Streets manual. GREEN STREET BMPs ID Name Included? HSC-3 Street trees (canopy interception) P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 19 BEST MANAGEMENT PRACTICES GREEN STREET BMPs ID Name Included? BIO-1 Stormwater Curb Extensions / Stormwater Planters BiO-1 Bioretention Areas INF-6 Permeable Pavement INF-6 Permeable Friction Course Overlays BIO-2 Vegetated Swales (composed amended where possible) BIO-3 Filter strips (amended road shoulder) BIO-7 Proprietary Biotreatment INF-2 Infiltration Trench TRT-2 Cartridge Media Filters TRT-2 WSDOT Media Filter Drains Other: With an infiltration rate of 0.5 in/hr prior to application of a factor of safety for the western-most portion of the project site, infiltration BMPs were considered infeasible for treatment of runoff from Nicky Way. In addition, the utilities in the proposed public street restricts available space for placement of infiltration BMPs. Based on other roadway constraints, proprietary biotreatment (BIO-7) via Modular Wetland Systems (MWS) are proposed. Three such units (MWS #3, #4, and #5) are proposed to treat the runoff from Nicky Way (2) and the frontage along Santiago Canyon Road (1). See Section IV.3.4 for further details and BMP sizing discussion. IV.3.2 Infiltration BMPs Infiltration BMPs are LID BMPs that capture, store and infiltrate storm water runoff. These BMPs are engineered to store a specified volume of water and have no design surface discharge (underdrain or outlet structure) until this volume is exceeded. Examples of infiltration BMPs include infiltration trenches, bioretention without underdrains, drywells, permeable pavement, and underground infiltration galleries. TABLE 5. INFILTRATION BMPS ID Name Included? INF-3 INF-4 Bioretention Without Underdrains Rain Gardens Porous Landscaping P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 20 BEST MANAGEMENT PRACTICES TABLE 5. INFILTRATION BMPS ID Name Included? Infiltration Planters Retention Swales INF-2 Infiltration Trenches INF-1 Infiltration Basins INF-5 Drywells INF-7 Subsurface Infiltration Galleries -- French Drains INF-6 Permeable Asphalt Permeable Concrete Permeable Concrete Pavers Other: Infiltration was measured to be feasible for the central and eastern of the project site with an average infiltration rate of 2.4 inches/hour prior to application of a factor of safety. Because the project site will be left in a rough grade condition, infiltration BMPs will not be implemented as part of the current project until the development of the respective lots for build-out conditions at a future date. Nevertheless, the DMAs have been sized for the implementation of a bioretention without underdrain (INF-3) based on TGD methodology in order to give full disclosure of the required build-out water quality conditions for these 6 lots and to demonstrate the potential scale and locations of infiltration BMPs. Each conceptual bioretention system is sized for a ponding depth of 6 inches, a minimum media filtration layer of 2 feet and gravel storage depth of 1.5 feet. The table below calculates the minimum square footage required for each DMA to accommodate a conceptual 800 square foot bioretention system, based on the average infiltration rate of 2.4 inches per hour and its ability to draw-down in 16 hours (Capture Efficiency Method). The Preliminary WQMP Exhibit found in Section VI show the conceptual location and footprints of these infiltrating BMPs. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 21 BEST MANAGEMENT PRACTICES BIORETENTION DESIGN SUMMARY: 80% CAPTURE EFFICIENCY METHOD DMA(1) Total Drainage Area (ac) BMP Effective Depth (ft) BMP Drawdown Time (hours) Fraction of Design Capture Storm Depth(2,3) 80% Capture Design Storm Depth(3) 80% Capture DCV (ft3)(3) BMP Surface Area Needed (ft2) BMP Surface Area Provided (ft2) DMA 1 0.856 1.6 16 0.64 0.544 in 887.4 554.6 800 DMA 2 0.984 1.6 16 0.64 0.544 in 1,020.1 637.6 800 DMA 3 0.949 1.6 16 0.64 0.544 in 983.9 614.9 800 DMA 4 1.142 1.6 16 0.64 0.544 in 1,183.9 740.0 800 DMA 5 1.167 1.6 16 0.64 0.544 in 1,209.9 756.2 800 DMA 6 0.954 1.6 16 0.64 0.544 in 989.0 618.1 800 Notes: (1) Refer to WQMP Exhibit in Section VI for locations of DMAs and proposed BMPs. (2) Per Figure III.2 of the TGD. See also Worksheet C in Section IV.8. (3) Per Worksheet C, “Determining Capture Efficiency of Volume Based, Constant Drawdown BMPs.” Copies of completed worksheets with detailed calculations are included in Section IV.8. It is also worth noting that infiltrating BMPs conceptually proposed for Lots 2, 3 & 4 will be in significantly deep fill conditions with higher infiltration rates. Should it be determined that fill materials beneath the BMPs will inhibit the infiltration of runoff, storm water drywells may be implemented within the bioretention sump to allow the BMP to penetrate through the fill and infiltrate into the underlying soils with high percolation rates. Further details on the proposed BMP designs, including final locations, footprints, design infiltration rates and drawdown times will be provided in the future, separate Final WQMP(s). IV.3.3 Evapotranspiration & Rainwater Harvesting BMPs TABLE 6. EVAPOTRANSPIRATION, RAINWATER HARVESTING ID Name Included? -- HSCs, see Section IV.3.1 -- Surface-based infiltration BMPs -- Biotreatment BMPs, see Section VI.3.4 HU-1 Above-ground cisterns and basins HU-2 Underground detention -- Other: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 22 BEST MANAGEMENT PRACTICES Since infiltration BMPs will be utilized on-site, evapotranspiration and harvest and reuse BMPs were not evaluated for the project. IV.3.4 Biotreatment BMPs TABLE 7. BIOTREATMENT BMPS ID Name Included? BIO-1 Bioretention with underdrains Storm Water planter boxes with underdrains Rain gardens with underdrains BIO-5 Constructed wetlands BIO-2 Vegetated swales BIO-3 Vegetated filter strips BIO-7 Proprietary vegetated biotreatment systems BIO-4 Wet extended detention basin BIO-6 Dry extended detention basins -- Other: Biotreatment BMPs will be utilized on-site for water quality treatment of the proposed public street as well as the proposed street improvements on Nicky Way and Santiago Canyon Road. The project will implement a series of proprietary biotreatment systems for water quality treatment to treat all pollutants of concern to a medium to high level of effectiveness. The systems will include the Modular Wetlands Systems developed by Bio Clean Environmental Services, Inc. Modular Wetlands by Modular Wetlands Systems, Inc. are proprietary biotreatment systems that utilize multi-stage treatment processes including screening media filtration, settling, and biofiltration. The pre- treatment chamber contains the first three stages of treatment and includes a catch basin inlet filter to capture trash, debris, gross solids and sediments, a settling chamber for separating out larger solids, and a media filter cartridge for capturing fine TSS, metals, nutrients, and bacteria. Runoff then flows through the wetland chamber where treatment is achieved through a variety of physical, chemical, and biological processes. As storm water passes down through the planting soil, pollutants are filtered, adsorbed, biodegraded and sequestered by the soil and plants, functioning similar to bioretention systems. The discharge chamber at the end of the unit collects treated flows and discharges back into the storm drain system. These systems were selected based on their ability to treat the project’s pollutants of concerns to a medium or high effectiveness, in accordance with the Model WQMP, TGD requirements and Green Streets Manual. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 23 BEST MANAGEMENT PRACTICES Five Modular Wetland System (MWS) units will be installed to treat on-site property runoff. Once low flows have been treated through the Modular Wetland units, the treated runoff will drain to the existing Handy Creek below Nicky Way before flowing northward to the Santiago Creek Channel. All high flows along Nicky Way will bypass the BMPs and drain directly to a proposed catch basin and existing storm drain lines that connect to the Santiago Creek Channel. In accordance with the Model WQMP and TGD, the bioretention/biotreatment BMPs will be sized to treat runoff from the Design Capture Storm (85th percentile, 24-hour). Since Modular Wetlands are sized based on flow rate, they were sized utilizing the methodology for flow based BMPs (TGD Section III.1.2 and Worksheet D). MODULAR WETLAND SYSTEM DESIGN SUMMARY DMA & BMP ID(1) Area (ac) % Imp. 2-Year Tc (min) Rainfall Intensity (in/hr) QDesign(3) (cfs) Size / Model(4) Combined Treatment Capacity (5) (cfs) DMA 7 MWS #1 0.389 100% 5 0.26 0.091 MWS-L-4-8-C 0.115 DMA 8 MWS #2 0.276 100% 5 0.26 0.065 MWS-L-4-6-C 0.073 DMA 9 MWS #3 0.418 70% 5 0.26 0.073 MWS-L-4-6-C 0.073 DMA 10 MWS #4 0.509 50% 5 0.26 0.069 MWS-L-4-6-C 0.073 DMA 11 MWS #5 0.951 20% 5 0.26 0.074 MWS-L-4-8-V 0.115 Notes: (1) See also Section IV.2.2. (2) Refer to WQMP Exhibit in Section VI for locations of each drainage area and BMP. (3) Detailed calculations and worksheets are included in Section IV.8. (4) Unit details and specifications are included in Section VI. (5) Treatment capacities of each unit are based on wetland media design loading rate (controlled by downstream orifice) and perimeter surface area of wetland media provided. Individual unit sizing calculations provided by the manufacturer are included on each cut sheet/detail included in Section VI. Locations and tributary drainage areas are shown on the Preliminary WQMP Exhibit included in Section VI. BMP details and cross sections are included in Appendix C. Detailed calculations and associated TGD Worksheets are included in Section IV.8. Operation and maintenance details are included in Section V and Appendix D (O&M Plan). IV.3.5 Hydromodification Control BMPs Not applicable. No hydromodification impacts will exist for the proposed project, since the project site will be more pervious in its rough graded post-development condition than in pre-development with an existing asphalt parking lot. Furthermore, proposed infiltration BMPs on the proposed residential lots for the ultimate build-out condition will provide more volume infiltrated than the 4,792 ft3 of runoff to P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 24 BEST MANAGEMENT PRACTICES be retained to mitigate HCOCs. LID infiltration BMPs, at 80% capture efficiency design, will be infiltrating a minimum of 7680 ft3 of storm water runoff with a 16-hour drawdown time (see Section IV.3.2), which is 160% of the required HCOC retention volume. IV.3.6 Regional/Sub-Regional LID BMPs Not applicable. LID BMPs will be utilized for water quality treatment on-site in accordance with the MS4 Permit hierarchy identified at the beginning of this Section. IV.3.7 Treatment Control BMPs Not applicable. LID BMPs will be utilized for water quality treatment on-site in accordance with the MS4 Permit hierarchy identified at the beginning of this Section. IV.4 WATER QUALITY CREDITS Not applicable. Water quality credits will not be applied for the project. LID BMPs will be utilized for water quality treatment on-site in accordance with the MS4 Permit hierarchy identified at the beginning of this Section. IV.5 ALTERNATIVE COMPLIANCE PLAN INFORMATION Not applicable. LID BMPs will be utilized for water quality treatment on-site in accordance with the MS4 Permit hierarchy identified at the beginning of this Section. IV.6 VECTOR CONTROL Vector control issues are not considered an issue since all proposed infiltration systems will be subterranean within closed systems. The proposed bioretention facilities will infiltrate a 6-inch ponding depth within 5 hours, and the 80% capture volume within 16 hours. Any water remaining in the bioretention systems after completion of rain events will infiltrate within 48 hours. IV.7 DRAINAGE MANAGEMENT AREAS In accordance with the MS4 permit and the 2011 Model WQMP, the project site has been divided into Drainage Management Areas (DMAs) to be utilized for defining drainage areas and sizing LID and other treatment control BMPs. DMAs have been delineated based on the proposed site grading patterns, drainage patterns, storm drain and catch basin locations. The design capture volumes (DCV) and treatment flow rates (QDesign) for each DMA are summarized in the table below. These have been derived utilizing the “Simple Method” in accordance with the TGD Section III.1.1. Actual BMP sizing requirements, including 80 percent capture design volumes, flow rates, depths, and other design details for the specific BMPs proposed are provided in Section IV.8 below. Locations of DMAs and associated LID and treatment BMPs are identified on the exhibits in Section VI. Additional calculations and TGD Worksheets are provided in Section IV.8. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 25 BEST MANAGEMENT PRACTICES DRAINAGE MANAGEMENT AREAS (DMAs) DMA/ Drainage Area ID(1) BMP Tributary Drainage Area (ac) % Imp. Design Storm Depth(2) (in) Estimated Tc (min) Rainfall Intensity(3) (in/hr) Simple Method DCV(4) (ft3) QDesign (5) (cfs) DMA 1 Bioretention 0.856 50.0% 0.85 5 0.26 1,386.6 0.117 DMA 2 Bioretention 0.984 50.0% 0.85 5 0.26 1,594.0 0.134 DMA 3 Bioretention 0.949 50.0% 0.85 5 0.26 1,537.3 0.130 DMA 4 Bioretention 1.142 50.0% 0.85 5 0.26 1,849.9 0.156 DMA 5 Bioretention 1.167 50.0% 0.85 5 0.26 1,890.4 0.159 DMA 6 Bioretention 0.954 50.0% 0.85 5 0.26 1,545.4 0.130 DMA 7 MWS #1 0.389 100.0% 0.85 5 0.26 1,080.2 0.091 DMA 8 MWS #2 0.276 100.0% 0.85 5 0.26 766.4 0.065 DMA 9 MWS #3 0.418 70.0% 0.85 5 0.26 870.6 0.073 DMA 10 MWS #4 0.509 50.0% 0.85 5 0.26 824.5 0.069 DMA 11 MWS #5 0.951 20.0% 0.85 5 0.26 880.3 0.074 Notes: 1. Refer to exhibits in Section VI for locations of each DMA. 2. Per Figure XVI-1 of the Technical Guidance Document. 3. Per Figure III.4 of the Technical Guidance Document. 4. Per Section III.1.1 of the Technical Guidance Document. 5. Per Section III.3.3 and Worksheet D of the Technical Guidance Document. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 26 BEST MANAGEMENT PRACTICES IV.8 CALCULATIONS IV.8.1 Design Capture Volume (DCV) In accordance with Section III.1.1 and Worksheet B of the TGD, the project DCV is calculated as follows: ܦܥܸൌܥ ൈ݀ ൈܣ ൈ43,560ݏ݂ ܽܿ ൈ 1 12 ݂ݐ/݅݊ ܥ ൌ ሺ0.75 ൈ ݅݉ 0.15ሻ Where: DCV = design capture volume, in ft3 C = runoff coefficient Imp = impervious fraction of drainage area d = storm depth per Figure XVI-1, in inches A = tributary area, in acres Refer to Worksheet B for DCV calculations for the individual DMAs. Worksheet B: Simple Design Capture Volume Sizing MethodProject: TTM 17847Date: 8/1/2018DMA =Total TTMTotal DMAsDMA 1 DMA 2 DMA 3 DMA 4 DMA 5 DMA 6 DMA 7 DMA 8 DMA 9 DMA 10 DMA 111Enter design capture storm depth from Figure III.1, d (inches)d= 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 inches2Enter the effect of provided HSCs, dHSC (inches) (Worksheet A)dHSC=0 0 0 0 0 0 0 0 0 0 0 0 0 inches3Calculate the remainder of the design capture storm depth, dremainder (inches) (Line 1 – Line 2)dremainder=0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 0.85 inches1Enter Project area tributary to BMP(s), A (acres)A= 7.433 8.595 0.856 0.984 0.949 1.142 1.167 0.954 0.389 0.276 0.418 0.509 0.951 acres2Enter Project Imperviousness, imp (unitless) imp= 50.0% 50.0% 50.0% 50.0% 50.0% 50.0% 50.0% 50.0% 100.0% 100.0% 70.0% 50.0% 20.0% %3Calculate runoff coefficient, C= (0.75 x imp) + 0.15C= 0.525 0.525 0.525 0.525 0.525 0.525 0.525 0.525 0.900 0.900 0.675 0.525 0.3004Calculate runoff volume, Vdesign= (C x dremainder x A x 43560 x (1/12))Vdesign=12,040.6 13,922.9 1,386.6 1,594.0 1,537.3 1,849.9 1,890.4 1,545.4 1,080.2 766.4 870.6 824.5 880.3 cu-ft1Enter measured infiltration rate, Kmeasured (in/hr) (Appendix VII)Kmeasured=2.40 2.40 2.40 2.40 2.40 2.40 2.40 2.40 -- -- -- -- -- in/hr2Enter combined safety factor from Worksheet H, Sfinal (unitless)Sfinal=2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 -- -- -- -- --3Calculate design infiltration rate, Kdesign = Kmeasured / SfinalKdesign=1.20 1.20 1.20 1.20 1.20 1.20 1.20 1.20 -- -- -- -- -- in/hr4 Enter drawdown time, T (max 48 hours) T= 48 48 48 48 48 48 48 48 hours5Calculate max retention depth that can be drawn down within the drawdown time (feet), Dmax = Kdesign x T x (1/12)Dmax=4.80 4.80 4.80 4.80 4.80 4.80 4.80 4.80 feet6Calculate minimum area required for BMP (sq-ft), Amin = Vdesign/ dmaxAmin=2,508.5 2,900.6sq-ftN/A - see Worksheet DSee Worksheet C for bioretention with underdrains sizingStep 1: Determine the design capture storm depth used for calculating volumeStep 2: Calculate the DCVStep 3: Design BMPs to ensure full retention of the DCVStep 3b: Determine minimum BMP footprintStep 3a: Determine design infiltration rateF:\Projects\881\003\_Support Files\Reports\WQMP\Appendices\_BMP Calcs & worksheets\WQ Calcs Worksheets TTM 17849_2018-08-02; B-18/2/2018 P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 28 BEST MANAGEMENT PRACTICES Table 2.7: Infiltration BMP Feasibility Worksheet Infeasibility Criteria Yes No 1 Would Infiltration BMPs pose significant risk for groundwater related concerns? Refer to Appendix VII (Worksheet I) for guidance on groundwater-related infiltration feasibility criteria. X Provide basis: See Worksheet I 2 Would Infiltration BMPs pose significant risk of increasing risk of geotechnical hazards that cannot be mitigated to an acceptable level? (Yes if the answer to any of the following questions is yes, as established by a geotechnical expert): The BMP can only be located less than 50 feet away from slopes steeper than 15 percent The BMP can only be located less than eight feet from building foundations or an alternative setback. A study prepared by a geotechnical professional or an available watershed study substantiates that stormwater infiltration would potentially result in significantly increased risks of geotechnical hazards that cannot be mitigated to an acceptable level. X Provide basis: Proposed infiltration BMPs will be located at least 50 feet from slopes. 3 Would infiltration of the DCV from drainage area violate downstream water rights? X Provide basis: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 29 BEST MANAGEMENT PRACTICES Table 2.7: Infiltration BMP Feasibility Worksheet (continued) Partial Infeasibility Criteria Yes No 4 Is proposed infiltration facility located on HSG D soils or the site geotechnical investigation identifies presence of soil characteristics which support categorization as D soils? X Provide basis: Per TGD Figure XVI-2b, the project is not located in an area with Type D soils. 5 Is measured infiltration rate below proposed facility less than 0.3 inches per hour? This calculation shall be based on the methods described in Appendix VII. X Provide basis: Based on an infiltration test conducted by Ginter and Associates, Inc., infiltration was deemed feasible with an average rate of 2.4 in/hr prior to application of a factor of safety were found. See Appendix E for details. 6 Would reduction of over predeveloped conditions cause impairments to downstream beneficial uses, such as change of seasonality of ephemeral washes or increased discharge of contaminated groundwater to surface waters? X Provide citation to applicable study and summarize findings relative to the amount of infiltration that is permissible: 7 Would an increase in infiltration over predeveloped conditions cause impairments to downstream beneficial uses, such as change of seasonality of ephemeral washes or increased discharge of contaminated groundwater to surface waters? X Provide citation to applicable study and summarize findings relative to the amount of infiltration that is permissible: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 30 BEST MANAGEMENT PRACTICES Table 2.7: Infiltration BMP Feasibility Worksheet (continued) Infiltration Screening Results (check box corresponding to result): 8 Is there substantial evidence that infiltration from the project would result in a significant increase in I&I to the sanitary sewer that cannot be sufficiently mitigated? (See Appendix XVII) Provide narrative discussion and supporting evidence: Summarize findings of studies provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. N/A 9 If any answer from row 1-3 is yes: infiltration of any volume is not feasible within the DMA or equivalent. Provide basis: Summarize findings of infeasibility screening 10 If any answer from row 4-7 is yes, infiltration is permissible but is not presumed to be feasible for the entire DCV. Criteria for designing biotreatment BMPs to achieve the maximum feasible infiltration and ET shall apply. Provide basis: Summarize findings of infeasibility screening 11 If all answers to rows 1 through 11 are no, infiltration of the full DCV is potentially feasible, BMPs must be designed to infiltrate the full DCV to the maximum extent practicable. X P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 31 BEST MANAGEMENT PRACTICES Worksheet I: Summary of Groundwater-related Feasibility Criteria 1 Is project large or small? (as defined by Table VIII.2) circle one Large Small 2 What is the tributary area to the BMP? A 6.05 acres 3 What type of BMP is proposed? Bioretention without underdrains 4 What is the infiltrating surface area of the proposed BMP? ABMP 4,800 sq-ft 5 What land use activities are present in the tributary area (list all) Estate residential lots. 6 What land use-based risk category is applicable? L M H 7 If M or H, what pretreatment and source isolation BMPs have been considered and are proposed (describe all): 8 What minimum separation to mounded seasonally high groundwater applies to the proposed BMP? See Section VIII.2 (circle one) 5 ft 10 ft 9 Provide rationale for selection of applicable minimum separation to seasonally high mounded groundwater: Bioretention without underdrains per Section VIII.2 of the TGD. 10 What is separation from the infiltrating surface to seasonally high groundwater? SHGWT ~30 ft ft 11 What is separation from the infiltrating surface to mounded seasonally high groundwater? Mounded SHGWT ~30 ft ft 12 Describe assumptions and methods used for mounding analysis: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 32 BEST MANAGEMENT PRACTICES Worksheet I: Summary of Groundwater-related Feasibility Criteria 13 Is the site within a plume protection boundary (See Figure VIII.2)? Y N N/A 14 Is the site within a selenium source area or other natural plume area (See Figure VIII.2)? Y N N/A 15 Is the site within 250 feet of a contaminated site? Y N N/A 16 If site-specific study has been prepared, provide citation and briefly summarize relevant findings: Groundwater is approximately 34-52 feet below ground surface in the vicinity of the project site. 17 Is the site within 100 feet of a water supply well, spring, septic system? Y N N/A 18 Is infiltration feasible on the site relative to groundwater- related criteria? Y N Provide rationale for feasibility determination: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 33 BEST MANAGEMENT PRACTICES Table VIII.1: Recommendations/Requirements for BMP Selection to Minimize Groundwater Quality Impacts Tributary Area Risk Category Narrative Description of Category Example Land Use Activities BMP Selection Requirements Low Runoff Contamination Potential BMP receives runoff from a mix of land covers that are expected to have relatively clean runoff; significant spills in tributary area are unlikely. Rooftops with roofing material and downspouts free of copper and zinc Patios, sidewalks, and other pedestrian areas Mixed residential land uses with applicable source controls Institutional land uses with applicable source controls Driveways and minor streets Any infiltration BMP type may be used Pretreatment for sediment is strongly recommended, as applicable, to mitigate clogging Moderate Runoff Contamination Potential BMP receives runoff from a mix of land covers, more than 10 percent of which have the potential to generate stormwater pollutants at levels that could potentially contaminate groundwater; there is potential for minor spills in the tributary area. Roadways greater than 5,000 ADT but less than 25,000 ADT Commercial and institutional parking lots Commercial land uses Light industrial that does not include usage of chemicals that are mobile in stormwater and groundwater Trash storage areas Any infiltration BMP type may be used Pretreatment shall be used The type of pretreatment shall be selected to address potential groundwater contaminants potentially found in stormwater runoff. High Runoff Contamination Potential BMP receives runoff from a mix of land covers, more than 10 percent of which have significant unavoidable potential to generate stormwater pollutants in quantities that could be detrimental to groundwater quality; and/or there is significant potential for major spills that could drain to BMPs. Roads greater than 25,000 ADT Heavy and light industrial pollutant source areas, including areas with exposed industrial activity and high use industrial truck traffic, and any areas that cannot be isolated these areas. Does not include lower risk source sources areas within industrial zones (e.g., roofs, offices, and parking areas) that are hydrologically isolated from industrial pollutant source areas Automotive repair shops Car washes Fleet storage areas Nurseries, agriculture, and heavily managed landscape areas with extensive use of fertilizer Fueling stations (infiltration prohibited under all conditions) Infiltration is prohibited unless advanced pretreatment and spill isolation can be feasibly used and enhanced monitoring and inspection are implemented. Large projects* must evaluate feasibility of advanced pretreatment and spill isolation. Small projects may consider infiltration to be infeasible with narrative discussion * See Table VII.2 for definition of “Large” and “Small” projects. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 34 BEST MANAGEMENT PRACTICES Table VIII.2: Definition of Project Site Categories Residential Commercial, Institutional Industrial Small Projects Less than 10 acres and less than 30 DU Less than 5 acres and less than 50,000 SF Less than 2 acres and less than 20,000 SF Large Projects Greater than 10 acres or greater than 30 DU Greater than 5 acres or greater than 50,000 SF Greater than 2 acres or greater than 20,000 SF VIII.2. Depth to Groundwater and Mounding Potential Minimum separation between the infiltrating surface (bottom of infiltration facility) and seasonally high mounded groundwater shall be observed in the design of infiltration BMPs, depending on BMP type. If the depth to unmounded seasonally high groundwater is greater than 15 feet, the depth to groundwater does not constrain infiltration If separation to unmounded seasonally high groundwater is greater than 10-feet and the infiltration area is less than 2,000 sq-ft, the depth to groundwater does not constrain infiltration. The separation between the infiltrating surface and the seasonally high mounded groundwater table shall not be less than 5 feet for all BMP types. BMPs for which 5-foot minimum separation applies include: o Rain gardens and dispersion trenches (small, residential applications) o Bioretention and planters o Permeable Pavement o Similar BMPs infiltrating over an extensive surface area and providing robust pretreatment or embedded treatment processes. Separation to mounded seasonally high groundwater shall be at least 10 feet for infiltration devices that inject water below the subsurface and surface infiltration BMPs with tributary area and land use activities that are considered to pose a more significant risk to groundwater quality. BMPs for which the 10-foot separation applies include: o Dry wells o Subsurface infiltration galleries or vaults o Surface Infiltration Basins o Infiltration Trenches o Other functionally similar devices or BMPs. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 35 BEST MANAGEMENT PRACTICES IV.8.2 Bioretention Without Underdrains BMP Design (Capture Efficiency Method) In accordance with Section III.3.2 and Worksheet C of the TGD, the project’s 80% Capture DCV is calculated as follows: ܦܥܸ ൌ ܥ ൈ ݀௧ ൈ ܣ ൈ 43,560 ݏ݂ ܽܿ ൈ 1 12 ݂ݐ/݅݊ ܥ ൌ ሺ0.75 ൈ ݅݉ 0.15ሻ ݀௧ ൌ ሺܺଵ െܺଶሻ ൈ݀ Where: DCV = design capture volume, in ft3 C = runoff coefficient Imp = impervious fraction of drainage area dfraction = resultant design capture storm depth for capture efficiency method d = storm depth per Figure XVI-1, in inches X1 = fraction of design capture storm depth at which BMP drawdown time achieves 80% capture efficiency X2 = design capture storm depth at which the drawdown time achieves equivalent of upstream capture efficiency A = tributary area, in acres dfraction Refer to Worksheet C for DCV calculations for the individual DMAs. Further details on the proposed BMP designs, including final locations, footprints, design infiltration rates and drawdown times will be provided in the future, separate Final WQMP(s). Worksheet C: Capture Efficiency Method for Volume-Based, Constant Drawdown BMPsDMA= DMA 1 DMA 2 DMA 3 DMA 4 DMA 5 DMA 61Enter design capture storm depth from Figure III.1, d (inches)d= 0.85 0.85 0.85 0.85 0.85 0.85 inches2Enter calculated drawdown time of the proposed BMP based on equation provided in applicable BMP Fact Sheet, T (hours)T= 16.0 16.0 16.0 16.0 16.0 16.0 hours3Using Figure III.2, determine the "fraction of design capture storm depth" at which the BMP drawdown time (T) line achieves 80% capture efficiency, X1X1=0.64 0.64 0.64 0.64 0.64 0.644Enter the effect depth of provided HSCs upstream, dHSC (inches) (Worksheet A)dHSC=0.00 0.00 0.00 0.00 0.00 0.00 inches5Enter capture efficiency corresponding to dHSC, Y2 (Worksheet A)Y2=0% 0% 0% 0% 0% 0% %6Using Figure III.2, determine the fraction of "design capture storm depth" at which the drawdown time (T) achieves the equivalent of the upstream capture efficiency (Y2), X2X2=0000007Calculate the fraction of design volume that must be provided by BMP, fraction = X1 - X2fraction= 0.64 0.64 0.64 0.64 0.64 0.648Calculate the resultant design capture storm depth (inches), dfraction= fraction × d dfraction=0.5440 0.5440 0.5440 0.5440 0.5440 0.5440 inches9SOC Only: When using this method for biofiltration sizing, check that the resulting volume in pre-filter detention volume plus pore spaces is at least 0.75 of the remaining DCV (See Section III.7 and Worksheet SOC-1).Y / N / NA N/A N/A N/A N/A N/A N/A1Enter Project area tributary to BMP(s), A (acres)A= 0.856 0.984 0.949 1.142 1.167 0.954 acres2Enter Project Imperviousness, imp (unitless) imp= 50.0% 50.0% 50.0% 50.0% 50.0% 50.0% %3Calculate runoff coefficient, C= (0.75 x imp) + 0.15C= 0.525 0.525 0.525 0.525 0.525 0.5254Calculate runoff volume, Vdesign= (C x drfraction x A x 43560 x (1/12))Vdesign=887.4 1,020.1 983.9 1,183.9 1,209.9 989.0 cu-ftDescribe System:Bioretention without Underdrains (INF-3)Ponding Depth (dP) =0.5 0.5 0.5 0.5 0.5 0.5ftBioretention Media Depth (dM) =2.0 2.0 2.0 2.0 2.0 2.0ftBioretention Media Porosity (ηM)=25% 25% 25% 25% 25% 25%Gravel Reservoir Depth (dR) =1.5 1.5 1.5 1.5 1.5 1.5ftGravel Porosity (ηR)=40% 40% 40% 40% 40% 40%Reservoir Effective Depth (dEffective) =1.6 1.6 1.6 1.6 1.6 1.6ftVertical Design Infiltration Rate (KDesign) =1.2 1.2 1.2 1.2 1.2 1.2in/hrMinimum Surface Area Requierd (AMin) =554.6 637.6 614.9 740.0 756.2 618.1ft2 Total Infiltrating Surface Area Provided = 800.0 800.0 800.0 800.0 800.0 800.0ft2Total Volume Stored = 1,280.0 1,280.0 1,280.0 1,280.0 1,280.0 1,280.0ft3Provide drawdown time calculations per applicable BMP Fact Sheet:Drawdown (DD or T) = (ηR x dR) / (KDesign) x 12 Time to Drawdown Effective Depth (T) = 16.0 16.0 16.0 16.0 16.0 16.0hoursAssumed Drawdown for Calculation Purposes = 16.0 16.0 16.0 16.0 16.0 16.0hoursProject: TTM 17847Step 1: Determine the design capture storm depth used for calculating volumeStep 2: Calculate the DCVSupporting CalculationsF:\Projects\881\003\_Support Files\Reports\WQMP\Appendices\_BMP Calcs & worksheets\WQ Calcs Worksheets TTM 17849_2018-08-028/2/2018 TECHNICAL GUIDANCE DOCUMENT APPENDICES III-11 May 19, 2011 Figure III.2. Capture Efficiency Nomograph for Constant Drawdown Systems in Orange County P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 38 BEST MANAGEMENT PRACTICES IV.8.3 Modular Wetland System BMP Design The Modular Wetland System proprietary biotreatment BMPs were sized in accordance with Section III.1.2 and Worksheet D of the TGD: ܳ௦ ൌܥ ൈ݅ ൈܣ ܥ ൌ ሺ0.75 ൈ ݅݉ 0.15ሻ Where: QDesign = design flowrate, in cfs C = runoff coefficient Imp = impervious fraction of drainage area i = design intensity per Figure III.4, in inches per hour A = tributary area, in acres Refer to Worksheet D for flowrate calculations for the individual drainage areas/DMAs. Refer to Appendix C for additional design details and sizing information for the proposed Modular Wetland BMPs (provided by the manufacturer). Further details on the proposed BMP design including pipe sizes and inverts will be provided in the Final WQMP. Worksheet D: Capture Efficiency Method for Flow-Based BMPsProject: TTM 17847Date: 8/1/2018DMA 7 DMA 8 DMA 9 DMA 10 DMA 111Enter the time of concentration, Tc (min) (See Appendix IV.2)Tc=5.0 5.0 5.0 5.0 5.0 min2Using Figure III.4, determine the design intensity at which the estimated time of concentration (Tc) achieves 80% capture efficiency, I1I1=0.26 0.26 0.26 0.26 0.26 in/hr3Enter the effect depth of provided HSCs upstream, dHSC (inches) (Worksheet A)dHSC=00000inches4Enter capture efficiency corresponding to dHSC, Y2 (Worksheet A)Y2=0% 0% 0% 0% 0% %5Using Figure III.4, determine the design intensity at which the time of concentration (Tc) achieves the upstream capture efficiency (Y2), I2I2=00000in/hr6Determine the design intensity that must be provided by BMP, Idesign= I1 - I2Idesign=0.26 0.26 0.26 0.26 0.26 in/hr1Enter Project area tributary to BMP(s), A (acres)A= 0.389 0.276 0.418 0.509 0.951 acres2Enter Project Imperviousness, imp (unitless) imp= 100% 100% 70% 50% 20% %3Calculate runoff coefficient, C = (0.75 x imp) + 0.15C= 0.900 0.900 0.675 0.525 0.3004Calculate design flowrate, Qdesign= (C x idesign x A)Qdesign=0.091 0.065 0.073 0.069 0.074 cfsDescribe System:Proprietary BioTreatment (BIO-7):MWS #1MWS #2MWS #3MWS #4MWS #5Unit Size / Model = MWS-L-4-8-C MWS-L-4-6-C MWS-L-4-6-C MWS-L-4-6-C MWS-L-4-8-VUnit Size / Model Treatment Capacity = 0.115 0.073 0.073 0.073 0.115cfsNumber of Units Needed =11111Total Bio-treatment Provided = 0.115 0.073 0.073 0.073 0.115cfsProvide time of concentration assumptions:Assumed = 5 minutes for conservative estimateStep 1: Determine the design capture storm depth used for calculating volumeStep 2: Calculate the design flowrateSupporting CalculationsF:\Projects\881\003\_Support Files\Reports\WQMP\Appendices\_BMP Calcs & worksheets\WQ Calcs Worksheets TTM 17849_2018-08-02; D-1 (MWS) 8/2/2018 TECHNICAL GUIDANCE DOCUMENT APPENDICES III-13 May 19, 2011 Figure III.4. Capture Efficiency Nomograph for Off-line Flow-based Systems in Orange County P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 41 BMP INSPECTION & MAINTENANCE SECTION V IMPLEMENTATION, MAINTENANCE & INSPECTION RESPONSIBILITY FOR BMPs (O&M PLAN) It has been determined that Milan Capital Management, Inc., shall assume all BMP inspection and maintenance responsibilities for the TTM 17847 project. Contact Name: Pending – to be provided in Final WQMP Company: Milan Capital Management, Inc. Address: 888 South Disneyland Drive, Suite 101 Phone: 714.687.1900 BMPs located in the public streets and right-of-ways shall be maintained by the City of Orange. Should the maintenance responsibility be transferred at any time during the operational life of TTM 17847, such as when an HOA or POA is formed for a project, a formal notice of transfer shall be submitted to the City of Orange at the time responsibility of the property subject to this WQMP is transferred. The transfer of responsibility shall be incorporated into this WQMP as an amendment. The Owner shall verify BMP implementation and ongoing maintenance through inspection, self- certification, survey, or other equally effective measure. The certification shall verify that, at a minimum, the inspection and maintenance of all structural BMPs including inspection and performance of any required maintenance in the late summer / early fall, prior to the start of the rainy season. A form that may be used to record implementation, maintenance, and inspection of BMPs is included in Appendix D. The City of Orange may conduct verifications to assure that implementation and appropriate maintenance of structural and non-structural BMPs prescribed within this WQMP is taking place at the project site. The Owner shall retain operations, inspections and maintenance records of these BMPs and they will be made available to the City or County upon request. All records must be maintained for at least five (5) years after the recorded inspection date for the lifetime of the project. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 42 BMP INSPECTION & MAINTENANCE V.1 FREQUENCY INSPECTION MATRIX TABLE 8. BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Inspection/Maintenance Activities Minimum Frequency Responsible Party NON-STRUCTURAL SOURCE CONTROL BMPs N3, Common Area Landscape Management Maintenance shall be consistent with City requirements. Fertilizer and/or pesticide usage shall be consistent with City Guidelines for Use of Fertilizers (LIP Exhibit A-5.1V) as well as local requirements. Maintenance includes mowing, weeding, and debris removal on a weekly basis. Trimming, replanting, and replacement of mulch shall be performed on an as-needed basis to prevent exposure of erodible surfaces. Trimmings, clippings, and other landscape wastes shall be properly disposed of in accordance with local regulations. Materials temporarily stockpiled during maintenance activities shall be placed away from water courses and storm drain inlets. Monthly Milan Management Capital, Inc. N4, BMP Maintenance Maintenance of structural BMPs implemented at the project site shall be performed at the frequency prescribed in this WQMP. Records of inspections and BMP maintenance shall be kept by the Owner and shall be available for review upon request. Ongoing Milan Management Capital, Inc. City of Orange N11, Common Area Litter Control Litter patrol, violations investigations, reporting and other litter control activities shall be performed on a weekly basis and in conjunction with routine maintenance activities. Weekly Milan Management Capital, Inc. N12, Employee Training Educate all new employees/ managers on storm water pollution prevention, particularly good housekeeping practices, prior to the start of the rainy season (October 1). Refresher courses shall be conducted on an as needed basis. Annually Milan Management Capital, Inc. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 43 BMP INSPECTION & MAINTENANCE TABLE 8. BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Inspection/Maintenance Activities Minimum Frequency Responsible Party N14, Common Area Catch Basin Inspection Catch basin inlets and other drainage facilities shall be inspected after each storm event and once per year. Inlets and other facilities shall be cleaned prior to the rainy season, by October 1 each year. Annually City of Orange N15, Street Sweeping Private Streets and Parking Lots Public streets must be swept at least weekly, including prior to the start of the rainy season (October 1). Weekly City of Orange STRUCTURAL SOURCE CONTROL BMPs S1, SD-13, Provide storm drain system stenciling and signage Storm drain stencils shall be inspected for legibility, at minimum, once prior to the storm season, no later than October 1 each year. Those determined to be illegible will be re-stenciled as soon as possible. Annually City of Orange S4, SD-12, Use efficient irrigation systems & landscape design, water conservation, smart controllers, and source control Inspect, test and adjust irrigation system to eliminate overspray to hardscape areas, ensure timing and cycle lengths are correct. Weekly Visual inspection testing 2x per year Milan Management Capital, Inc. S5, Protect Slopes and Channels and Provide Energy dissipation To be performed in conjunction with maintenance activities. Maintain vegetative cover and/or mulch to eliminate exposed soils. Any eroded surfaces to be repaired immediately. Inspections to be performed twice each year (spring and fall) and after major storm events to check for signs of erosion, gullies, and sloughing. Monthly Milan Management Capital, Inc. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 44 BMP INSPECTION & MAINTENANCE LOW IMPACT DEVELOPMENT (LID) BMPs BMP Inspection/Maintenance Activities Minimum Frequency Responsible Party Bioretention Without Underdrains Inspect BMPs routinely with general maintenance activities, as well as semi- annually or after major storm events to check for maintenance needs and function. Routine maintenance activities include: Maintain vegetation and media to perpetuate a robust vegetative and microbial community (thin/trim vegetation, replace spent media and mulch). Periodically remove dead vegetative biomass to prevent export of nutrients or clogging of the system. Remove accumulated sediment before it significantly interferes with system function. Conduct maintenance to prevent surface clogging (surface scarring, raking, mulch replacement, etc.). Maintain splash blocks/energy dissipation and scour-protection as required based on facility inspection. Routinely remove accumulated sediment at the inlet and outlet and trash and debris from the area. Repair torn or broken liners as necessary. Major maintenance shall be provided when the performance of the facility declines significantly and cannot be restored through routine maintenance. Major maintenance activities include: Replace media / planting soils as triggered by reduction in filtration/infiltration rates or decline in health of biological processes. Provide major sediment removal to restore volumetric capacity of basin-type BMPs. Repair or modify inlets/outlets to restore original function or enhance function based on observations of performance. 2x per year Milan Management Capital, Inc. Individual Homeowners P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 45 BMP INSPECTION & MAINTENANCE LOW IMPACT DEVELOPMENT (LID) BMPs BMP Inspection/Maintenance Activities Minimum Frequency Responsible Party Proprietary Biotreatment: Modular Wetland Systems (MWS) Per manufacturer’s specifications, the system shall be inspected at a minimum of once every six months, prior to the start of the rainy season (October 1) each year, and after major storm events. Typical maintenance includes: Removing trash & debris from the catch basin screening filter (by hand, 2x per year at a minimum). Removal of sediment and solids in the settlement chamber (vacuum truck, once per year at a minimum). Replacement of the BioMediaGREENTM filter cartridge and drain-down filter (if equipped, once per year at a minimum) Trim plants within the wetland chamber as needed in conjunction with routine landscape maintenance activities (typically 2x per year). No fertilizer shall be used. Wetland chamber should be inspected during rain events to verify flow through the system. If little to no flow is observed from the lower valve or orifice plate, the wetland media may require replacement. If prior treatment stages are properly maintained, the life of the wetland media can be up to 20 years. 2x per year City of Orange Any waste generated from maintenance activities will be disposed of properly. Wash water and other waste from maintenance activities is not to be discharged or disposed of into the storm drain system. Clippings from landscape maintenance (i.e. prunings) will be collected and disposed of properly off- site, and will not be washed into the streets, local area drains/conveyances, or catch basin inlets. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 46 BMP INSPECTION & MAINTENANCE V.2 REGULATORY PERMITS None are required. V.3 FUNDING Long-term funding for BMP maintenance along the public streets right-of-way will be provided by the City of Orange. Long-term funding for future BMPs within the six proposed residential estate lots will be provided by the Owner, Milan Capital Management, Inc. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 47 BMP INSPECTION & MAINTENANCE V.4 OWNER SELF-CERTIFICATION STATEMENT As the owner representative of the TTM 17847 project for which a Water Quality Management Plan (WQMP) was approved by the City, I hereby certify under penalty of law that all Best Management Practices contained within the approved Project WQMP have been maintained and inspected in accordance with the schedule and frequency outlined in the approved WQMP Maintenance Table. The maintenance activities and inspections conducted are shown in the attached table and have been performed by qualified and knowledgeable individuals. Structural Treatment BMPs have been inspected and certified by a licensed professional engineer. To the best of my knowledge, the information submitted is true and accurate and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fines and citations for violating water quality regulations. Signature: Date: Name: Title: Company: Address: Email: Telephone: P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 48 BMP INSPECTION & MAINTENANCE V.5 BMP IMPLEMENTATION TRACKING This sheet is to be submitted annually with the Owner Self Certification Statement. BMP IMPLEMENTATION TRACKING TABLE BMP Activity Completion Dates or Frequency Initial SOURCE CONTROL BMPS (STRUCTURAL AND NON-STRUCTURAL) N3, Common Area Landscape Management Maintain landscaping, restrict use of fertilizer & pesticides, properly dispose landscape wastes. Monthly N4, BMP Maintenance Maintain BMPs in accordance with Section V and Appendix D. Completion of construction, ongoing thereafter N11, Common Area Litter Control Litter pick-up and patrol. Weekly N12, Employee Training Educate all new employees/ managers on storm water pollution prevention practices. Upon hire, annually thereafter N14, Common Area Catch Basin Inspection Inspect catch basin inlets and clean out as necessary. Annually N15, Street Sweeping Private Streets and Parking Lots Sweep exposed parking areas & drive aisles. Weekly S1, Provide storm drain system stenciling and signage Inspect for legibility and re-stencil if needed. Annually S4, Use efficient irrigation systems & landscape design, water conservation, smart controllers, and source control Inspect, test and adjust irrigation system to eliminate overspray to hardscape areas, ensure timing and cycle lengths are correct. Weekly visual inspection Testing2x per year S5, Protect slopes and channels and provide energy dissipation Inspect vegetative cover. Check for signs of erosion, gullies, and sloughing 2x per year LOW IMPACT DEVELOPMENT AND TREATMENT BMPs* Bioretention Without Underdrains* Maintain landscaping, restrict use of fertilizer & pesticides, remove accumulated sediment, trash & debris 2x per year Modular Wetland System* Inspect settling chamber for sediment accumulation and clean out as necessary. Replace pre- treatment media filter. Evaluate for overall plant health. Prune, trim and/or replace vegetation as necessary. No fertilizer shall be used in wetland chamber. 2x per year * Structural Treatment BMPs should be certified by a Licensed Professional Engineer. P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 49 SITE PLAN & DRAINAGE PLAN SECTION VI LOCATION MAP, SITE PLAN AND BMP DETAILS The exhibits provided in this section are to illustrate the post construction BMPs prescribed within this WQMP. Drainage flow information of the proposed project, such as general surface flow lines, concrete or other surface drainage conveyances, and storm drain facilities are also depicted. All structural source control and treatment control BMPs are shown as well. EXHIBITS Vicinity Map Tentative Tract Map 17847 Preliminary WQMP Exhibit BMP DETAILS & FACT SHEETS (INCLUDED IN APPENDIX C) Bioretention Without Underdrains (INF-3) Proprietary Biotreatment (BIO-7) Modular Wetland Systems P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 50 SITE PLAN & DRAINAGE PLAN P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 53 EDUCATIONAL MATERIALS SECTION VII EDUCATIONAL MATERIALS The educational materials included in this WQMP are provided to inform people involved in future uses, activities, or ownership of the site about the potential pitfalls associated with careless storm water management. “The Ocean Begins at Your Front Door” provides users with information about storm water that is/will be generated on site, what happens when water enters a storm drain, and its ultimate fate, discharging into the ocean. Also included are activities guidelines to educate anyone who is or will be associated with activities that have a potential to impact storm water runoff quality, and provide a menu of BMPs to effectively reduce the generation of storm water runoff pollutants from a variety of activities. The educational materials that may be used for the proposed project are included in Appendix B of this WQMP and are listed below. EDUCATION MATERIALS Residential Materials (http://www.ocwatersheds.com) Check If Attached Business Materials (http://www.ocwatersheds.com) Check If Attached The Ocean Begins at Your Front Door Tips for the Automotive Industry Tips for Car Wash Fund-raisers Tips for Using Concrete and Mortar Tips for the Home Mechanic Tips for the Food Service Industry Homeowners Guide for Sustainable Water Use Proper Maintenance Practices for Your Business Household Tips Other Materials (http://www.ocwatersheds.com) (https://www.casqa.org/resources/b mp-handbooks) Check If Attached Proper Disposal of Household Hazardous Waste Recycle at Your Local Used Oil Collection Center (North County) DF-1 Drainage System Operation & Maintenance Recycle at Your Local Used Oil Collection Center (Central County) SD-10 Site Design & Landscape Planning Recycle at Your Local Used Oil Collection Center (South County) SD-12 Efficient Irrigation Tips for Maintaining Septic Tank Systems SD-13 Storm Drain Signage Responsible Pest Control Sewer Spill Tips for the Home Improvement Projects Tips for Horse Care Tips for Landscaping and Gardening Tips for Pet Care Tips for Pool Maintenance Tips for Residential Pool, Landscape and Hardscape Drains Tips for Projects Using Paint Tips for Protecting Your Watershed Other: Children’s Brochure P RELIMINARY W ATER Q UALITY M ANAGEMENT P LAN (WQMP) TTM 17847 AUGUST 1, 2018 MILAN CAPITAL MANAGEMENT, INC. 54 APPENDICES APPENDICES Appendix A .................................. Conditions of Approval, Resolution Number______ dated _______ Appendix B ................................................................................................... Educational Materials Appendix C ................................................................................................................ BMP Details Appendix D ................................................................... BMP Maintenance Information / O&M Plan Appendix E ....................................................................... Infiltration Testing & Geotechnical Report Appendix F .................................. Hydrology Information (Q2 – Two-year frequency storm evaluation) APPENDIX A CONDITIONS OF APPROVAL APPENDIX B EDUCATIONAL MATERIALS For More Information Aliso Viejo (949) 425-2535 Anaheim Public Works Operations (714) 765-6860 Brea Engineering (714) 990-7666 Buena Park Public Works (714) 562-3655 Costa Mesa Public Services (714) 754-5323 Cypress Public Works (714) 229-6740 Dana Point Public Works (949) 248-3584 Fountain Valley Public Works (714) 593-4441 Fullerton Engineering Dept (714) 738-6853 Garden Grove Public Works (714) 741-5956 Huntington Beach Public Works (714) 536-5431 Irvine Public Works (949) 724-6315 La Habra Public Services (562) 905-9792 La Palma Public Works (714) 690-3310 Laguna Beach Water Quality (949) 497-0378 Laguna Hills Public Services (949) 707-2650 Laguna Niguel Public Works (949) 362-4337 Laguna Woods Public Works (949) 639-0500 Lake Forest Public Works (949) 461-3480 Los Alamitos Community Dev (562) 431-3538 Mission Viejo Public Works (949) 470-3056 Newport Beach, Code & Water Quality Enforcement (949) 644-3215 Orange Public Works (714) 532-6480 Placentia Public Works (714) 993-8245 Rancho Santa Margarita (949) 635-1800 San Clemente Environmental Programs (949) 361-6143 San Juan Capistrano Engineering (949) 234-4413 Santa Ana Public Works (714) 647-3380 Seal Beach Engineering (562) 431-2527 x317 Stanton Public Works (714) 379-9222 x204 Tustin Public Works/Engineering (714) 573-3150 Villa Park Engineering (714) 998-1500 Westminster Public Works/Engineering (714) 898-3311 x446 Yorba Linda Engineering (714) 961-7138 Orange County Stormwater Program (877) 897-7455 Orange County 24-Hour Water Pollution Problem Reporting Hotline 1-877-89-SPILL (1-877-897-7455) On-line Water Pollution Problem Reporting Form w w w o c w a t e r s h e d s c o m The Ocean Begins at Your Front Door California Environmental Protection Agency www calepa ca gov • Air Resources Board www arb ca gov • Department of Pesticide Regulation www cdpr ca gov • Department of Toxic Substances Control www dtsc ca gov • Integrated Waste Management Board www ciwmb ca gov • Office of Environmental Health Hazard Assessment www oehha ca gov • State Water Resources Control Board www waterboards ca gov Earth 911 - Community-Specific Environmental Information 1-800-cleanup or visit www 1800cleanup org Health Care Agency’s Ocean and Bay Water Closure and Posting Hotline (714) 433-6400 or visit www ocbeachinfo com Integrated Waste Management Dept. of Orange County (714) 834-6752 or visit www oclandfills com for information on household hazardous waste collection centers, recycling centers and solid waste collection O.C. Agriculture Commissioner (714) 447-7100 or visit www ocagcomm com Stormwater Best Management Practice Handbook Visit www cabmphandbooks com UC Master Gardener Hotline (714) 708-1646 or visit www uccemg com Did You Know? Most people believe that the largest source of water pollution in urban areas comes from specific sources such as factories and sewage treatment plants In fact, the largest source of water pollution comes from city streets, neighborhoods, construction sites and parking lots This type of pollution is sometimes called “non-point source” pollution There are two types of non-point source pollution: stormwater and urban runoff pollution Stormwater runoff results from rainfall When rainstorms cause large volumes of water to rinse the urban landscape, picking up pollutants along the way Urban runoff can happen any time of the year when excessive water use from irrigation, vehicle washing and other sources carries trash, lawn clippings and other urban pollutants into storm drains Where Does It Go? Anything we use outside homes, vehicles and businesses – like motor oil, paint, pesticides, fertilizers and cleaners – can be blown or washed into storm drains A little water from a garden hose or rain can also send materials into storm drains Storm drains are separate from our sanitary sewer systems; unlike water in sanitary sewers (from sinks or toilets), water in storm drains is not treated before entering our waterways Printed on Recycled Paper The Orange County Stormwater Program has created and moderates an electronic mailing list to facilitate communications, take questions and exchange ideas among its users about issues and topics related to stormwater and urban runoff and the implementation of program elements To join the list, please send an email to ocstormwaterinfo-join@list ocwatersheds com Orange County Stormwater Program Even if you live miles from the Pacific Ocean, you may be unknowingly polluting it.Sources of Non-Point Source Pollution Automotive leaks and spills Improper disposal of used oil and other engine fluids Metals found in vehicle exhaust, weathered paint, rust, metal plating and tires Pesticides and fertilizers from lawns, gardens and farms Improper disposal of cleaners, paint and paint removers Soil erosion and dust debris from landscape and construction activities Litter, lawn clippings, animal waste, and other organic matter Oil stains on parking lots and paved surfaces The Effect on the OceanNon-point source pollution can have a serious impact on water quality in Orange County Pollutants from the storm drain system can harm marine life as well as coastal and wetland habitats They can also degrade recreation areas such as beaches, harbors and bays Stormwater quality management programs have been developed throughout Orange County to educate and encourage the public to protect water quality, monitor runoff in the storm drain system, investigate illegal dumping and maintain storm drains Support from Orange County residents and businesses is needed to improve water quality and reduce urban runoff pollution Proper use and disposal of materials will help stop pollution before it reaches the storm drain and the ocean Dumping one quart of motor oil into a storm drain can contaminate 250,000 gallons of water. Follow these simple steps to help reduce water pollution: Household Activities Do not rinse spills with water Use dry cleanup methods such as applying cat litter or another absorbent material, sweep and dispose of in the trash Take items such as used or excess batteries, oven cleaners, automotive fluids, painting products and cathode ray tubes, like TVs and computer monitors, to a Household Hazardous Waste Collection Center (HHWCC) For a HHWCC near you call (714) 834-6752 or visit www oclandfills com Do not hose down your driveway, sidewalk or patio to the street, gutter or storm drain Sweep up debris and dispose of it in the trash Automotive Take your vehicle to a commercial car wash whenever possible If you wash your vehicle at home, choose soaps, cleaners, or detergents labeled non-toxic, phosphate- free or biodegradable Vegetable and citrus-based products are typically safest for the environment Do not allow washwater from vehicle washing to drain into the street, gutter or storm drain Excess washwater should be disposed of in the sanitary sewer (through a sink or toilet) or onto an absorbent surface like your lawn Monitor your vehicles for leaks and place a pan under leaks Keep your vehicles well maintained to stop and prevent leaks Never pour oil or antifreeze in the street, gutter or storm drain Recycle these substances at a service station, a waste oil collection center or used oil recycling center For the nearest Used Oil Collection Center call 1-800-CLEANUP or visit www 1800cleanup org Never allow pollutants to enter the street, gutter or storm drain! Lawn and Garden Pet and animal waste Pesticides Clippings, leaves and soil Fertilizer Common Pollutants Automobile Oil and grease Radiator fluids and antifreeze Cleaning chemicals Brake pad dust Home Maintenance Detergents, cleaners and solvents Oil and latex paint Swimming pool chemicals Outdoor trash and litter The Ocean Begins at Your Front Door Trash Place trash and litter that cannot be recycled in securely covered trash cans Whenever possible, buy recycled products Remember: Reduce, Reuse, Recycle Pet Care Always pick up after your pet Flush waste down the toilet or dispose of it in the trash Pet waste, if left outdoors, can wash into the street, gutter or storm drain If possible, bathe your pets indoors If you must bathe your pet outside, wash it on your lawn or another absorbent/permeable surface to keep the washwater from entering the street, gutter or storm drain Follow directions for use of pet care products and dispose of any unused products at a HHWCC Pool Maintenance Pool and spa water must be dechlorinated and free of excess acid, alkali or color to be allowed in the street, gutter or storm drain When it is not raining, drain dechlorinated pool and spa water directly into the sanitary sewer Some cities may have ordinances that do not allow pool water to be disposed of in the storm drain Check with your city Landscape and Gardening Do not over-water Water your lawn and garden by hand to control the amount of water you use or set irrigation systems to reflect seasonal water needs If water flows off your yard onto your driveway or sidewalk, your system is over-watering Periodically inspect and fix leaks and misdirected sprinklers Do not rake or blow leaves, clippings or pruning waste into the street, gutter or storm drain Instead, dispose of waste by composting, hauling it to a permitted landfill, or as green waste through your city’s recycling program Follow directions on pesticides and fertilizer, (measure, do not estimate amounts) and do not use if rain is predicted within 48 hours Take unwanted pesticides to a HHWCC to be recycled For locations and hours of HHWCC, call (714) 834-6752 or visit www oclandfills com Pet Waste• Pollution: Pet waste carries bacteria through our watersheds and eventually will be washed out to the ocean. This can pose a health risk to swimmers and surfers. • Solution: Pick up after your pets! Trash and Debris• Pollution: Trash and debris can enter waterways by wind, littering and careless maintenance of trash receptacles. Street sweeping collects some of this trash; however, much of what isn’t captured ends up in our storm drain system where it flows untreated out to the ocean. • Solution: Don’t litter and make sure trash containers are properly covered. It is far more expensive to clean up the litter and trash that ends up in our waterways than it is to prevent it in the first place. Come out to one of Orange County’s many locations for Coastal and Inner-Coastal Cleanup Day, which is held in September. Motor Oil / Vehicle Fluids• Pollution: Oil and petroleum products from our vehicles are toxic to people, wildlife and plants. • Solution: Fix any leaks from your vehicle and keep the maintenance up on your car. Use absorbent material such as cat litter on oil spills, then sweep it up and dispose of it in the trash. Recycle used motor oil at a local Household Hazardous Waste Collection Center. Low Impact Development, Water Conservation & Pollution Prevention The Ocean Begins at Your Front Door DID YOU KNOW? Homeowners Guide for Sustainable Water Use A TEAM EFFORT The Orange County Stormwater Program has teamed with the Municipal Water District of Orange County (MWDOC) and the University of California Cooperative Extension Program (UCCE) to develop this pamphlet. Low Impact Development (LID) and sustainable water use prevents water pollution and conserves water for drinking and reuse. Reducing your water use and the amount of water flowing from your home protects the environment and saves you money. Thank you for making water protection a priority! For more information, please visit www.ocwatersheds. com/publiced/ www.mwdoc.com www.uccemg.com Pesticides and Fertilizer • Pollution: The same pesticides that are designed to be toxic to pests can have an equally lethal impact on our marine life. The same fertilizer that promotes plant growth in lawns and gardens can also create nuisance algae blooms, which remove oxygen from the water and clog waterways when it decomposes. • Solution: Never use pesticides or fertilizer within 48 hours of an anticipated rainstorm. Use only as much as is directed on the label and keep it off driveways and sidewalks. Dirt and Sediment• Pollution: Dirt or sediment can impede the flow of the stormwater and negatively impact stream habitat as it travels through waterways and deposits downstream. Pollutants can attach to sediment, which can then be transported through our waterways. • Solution: Protect dirt stockpiles by covering them with tarps or secure plastic sheets to prevent wind or rain from allowing dirt or sediment to enter the storm drain system. Metals• Pollution: Metals and other toxins present in car wash water can harm important plankton, which forms the base of the aquatic food chain. • Solution: Take your car to a commercial car wash where the wash water is captured and treated at a local wastewater treatment plant. The Pollution SolutionSeveral residential activities can result in water pollution. Among these activities are car washing and hosing off driveways and sidewalks. Both activities can waste water and result in excess runoff. Water conservation methods described in this pamphlet can prevent considerable amounts of runoff and conserve water. By taking your car to a commercial car wash and by sweeping driveways and sidewalks, you can further prevent the transport of pollutants to Orange County waterways. Here are some of the common pollutants for which you can be part of the solution: To report a spill, call the Orange County 24-Hour Water Pollution Prevention Reporting Hotline at 1-877-89-SPILL \ (1-877-897-7455) Special Thanks to The City of Los Angeles Stormwater Program for the use of its artwork The Metropolitan Water District of Southern California for the use of the California- Friendly Plant and Native Habitat photosDid you know that most of the pollution found in our waterways is not from a single source, but from a “non- point” source meaning the accumulation of pollution from residents and businesses throughout the community OPTIONS FOR RAINWATER HARvESTINg AND REUSE Rainwater harvesting is a great way to save money, prevent pollution and reduce potable water use. To harvest your rainwater, simply redirect the runoff from roofs and downspouts to rain barrels. Rain gardens are another option; these reduce runoff as well as encourage infiltration. Downspout Disconnection/Redirection Disconnecting downspouts from pipes running to the gutter prevents runoff from transporting pollutants to the storm drain. Once disconnected, downspouts can be redirected to rain gardens or other vegetated areas, or be connected to a rain barrel. Rain Barrels Rain barrels capture rainwater flow from roofs for reuse in landscape irrigation. Capacity of rain barrels needed for your home will depend on the amount of roof area and rainfall received. When purchasing your rain barrel, make sure it includes a screen, a spigot to siphon water for use, an overflow tube to allow for excess water to run out and a connector if you wish to connect multiple barrels to add capacity of water storage. Mosquito growth prevention is very important when installing a rain barrel. The best way to prevent mosquito breeding is to eliminate entry points by ensuring all openings are sealed tightly. If these methods are unsuccessful, products are available to kill mosquito larvae, but that are harmless to animals and humans. Regular application of these products is essential. Please visit the Orange County Vector Control website for more information at www.ocvcd.org/mosquitoes3.php. Rain Gardens Rain gardens allow runoff to be directed from your roof downspout into a landscaped area. Vegetation and rocks in the garden will slow the flow of water to allow for infiltration into the soil. Plants and soil particles will absorb pollutants from the roof runoff. By utilizing a native plant palate, rain gardens can be maintained all year with minimal additional irrigation. These plants are adapted to the semi-arid climate of Southern California, require less water and can reduce your water bill. Before modifying your yard to install a rain garden, please consult your local building and/or planning departments to ensure your garden plan follows pertinent building codes and ordinances. Besides codes and ordinances, some home owner associations also have guidelines for yard modifications. If your property is in hill areas or includes engineered slopes, please seek professional advice before proceeding with changes. R U N O F F , R A I N W A T E R A N D R E U S E For information on how to disconnect a downspout or to install and maintain a rain barrel or rain garden at your home, please see the Los Angeles Rainwater Harvesting Program, A Homeowner’s “How-To” Guide, November 2009 at www.larainwaterharvesting.org/ Water runoff from sprinklers left on too long will carry pollutants into our waterways. Permeable pavement allows water runoff to infiltrate through the soil and prevents most pollutants from reaching the storm drain system. What is Low Impact Development (LID)? Low Impact Development (LID) is a method of development that seeks to maintain the natural hydrologic character of an area. LID provides a more sustainable and pollution-preventative approach to water management. New water quality regulations require implementation of LID in larger new developments and encourage implementation of LID and other sustainable practices in existing residential areas. Implementing modifications to your lawn or garden can reduce pollution in our environment, conserve water and reduce your water bill. Where Does Water Runoff Go? Stormwater, or water from rainfall events, and runoff from outdoor water use such as sprinklers and hoses flows from homes directly into catch basins and the storm drain system. After entering the storm drain, the water flows untreated into streams, rivers, bays and ultimately the Pacific Ocean. Runoff can come from lawns, gardens, driveways, sidewalks and roofs. As it flows over hard, impervious surfaces, it picks up pollutants. Some pollutants carried by the water runoff include trash, pet waste, pesticides, fertilizer, motor oil and more. Water Conservation Pollution not only impairs the water quality for habitat and recreation, it can also reduce the water available for reuse. Runoff allowed to soak into the ground is cleaned as it percolates through the soil, replenishing depleted groundwater supplies. Groundwater provides at least 50% of the total water for drinking and other indoor household activities in north and central Orange County. When land is covered with roads, parking lots, homes, etc., there is less land to take in the water and more hard surfaces over which the water can flow. In Orange County, 60-70% of water used by residents and businesses goes to irrigation and other outdoor uses. Reusing rainwater to irrigate our lawn not only reduces the impact of water pollution from runoff, but it also is a great way to conserve our precious water resources and replenish our groundwater basin. Permeable pavement allows water runoff to infiltrate through the soil and prevents most pollutants from reaching the storm drain system. OTHER WATER CONSERvATION AND POLLUTION PREvENTION TECHNIqUES Native Vegetation and Maintenance “California Friendly” plants or native vegetation can significantly reduce water use. These plants often require far less fertilizers and pesticides, which are two significant pollutants found in Orange County waterways. Replacing water “thirsty” plants and grass types with water efficient natives is a great way to save water and reduce the need for potentially harmful pesticides and fertilizer. Please see the California Friendly Garden Guide produced by the Metropolitan Water District of Southern California and associated Southern California Water Agencies for a catalog of California friendly plants and other garden resources at www.bewaterwise.com/Gardensoft. Weed Free Yards Weeds are water thieves. They often reproduce quickly and rob your yard of both water and nutrients. Weed your yard by hand if possible. If you use herbicides to control the weeds, use only the amount recommended on the label and never use it if rain is forecast within the next 48 hours. Soil Amendments Soil amendments such as green waste (e.g. grass clippings, compost, etc.) can be a significant source of nutrients and can help keep the soil near the roots of plants moist. However, they can cause algal booms if they get into our waterways, which reduces the amount of oxygen in the water and impacts most aquatic organisms. It is important to apply soil amendments more than 48 hours prior to predicted rainfall. IRRIgATE EFFICIENTLY Smart Irrigation Controllers Smart Irrigation Controllers have internal clocks as well as sensors that will turn off the sprinklers in response to environmental changes. If it is raining, too windy or too cold, the smart irrigation control sprinklers will automatically shut off. Check with your local water agency for available re- bates on irrigation controllers and smart timers. • Aim your sprinklers at your lawn, not the sidewalk – By simply adjusting the direction of your sprinklers you can save water, prevent water pollution from runoff, keep your lawn healthy and save money. • Set a timer for your sprinklers – lawns absorb the water they need to stay healthy within a few minutes of turning on the sprinklers. Time your sprinklers; when water begins running off your lawn, you can turn them off. Your timer can be set to water your lawn for this duration every time. • Water at Sunrise – Watering early in the morning will reduce water loss due to evaporation. Additionally, winds tend to die down in the early morning so the water will get to the lawn as intended. • Water by hand – Instead of using sprinklers, consider watering your yard by hand. Hand- watering ensures that all plants get the proper amount of water and you will prevent any water runoff, which wastes water and carries pollutants into our waterways. • Fix leaks - Nationwide, households waste one trillion gallons of water a year to leaks – that is enough water to serve the entire state of Texas for a year. If your garden hose is leaking, replace the nylon or rubber hose washer and ensure a tight connection. Fix broken sprinklers immediately. Do your part to prevent water pollution in our creeks, rivers, bays and ocean. Clean beaches and healthy creeks, rivers, bays, and ocean are important to Orange County.However, many common household activities can lead to water pollution if you’re not careful. Litter, oil, chemicals and other substances that are left on your yard or driveway can be blown or washed into storm drains that flow to the ocean. Over-watering your lawn and washing your car can also flush materials into the storm drains. Unlike water in sanitary sewers (from sinks and toilets), water in storm drains is not treated. You would never pour soap, fertilizers or oil into the ocean, so don’t let them enter streets, gutters or storm drains. Follow the easy tips in this brochure to help prevent water pollution.GENUINE RECYCLED P APER 50% PRE-CONSUMER AND 15% POST-CONSUMER REMEMBER THE WATER IN YOUR STORM DRAIN IS NOT TREATED BEFORE IT ENTERS OUR WATERWAYS The Ocean Begins at Your Front Door For more information, please call the Orange County Stormwater Program at 1-877-89-SPILL (1-877-897-7455) or visit www.ocwatersheds.com To report a spill, call the Orange County 24-Hour Water Pollution Problem Reporting Hotline 1-877-89-SPILL (1-877-897-7455). For emergencies, dial 911. The tips contained in this brochure provide useful information to help prevent water pollution while performing everyday household activities. If you have other suggestions, please contact your city’s stormwater representatives or call the Orange County Stormwater Program. Help Prevent Ocean Pollution: Household Tips Gardening Activities �Follow directions on pesticides and fertilizers, (measure, do not estimate amounts) and do not use if rain is predicted within 48 hours. �Water your lawn and garden by hand to control the amount of water you use. Set irrigation systems to reflect seasonal water needs. If water flows off your yard and onto your driveway or sidewalk, your system is over-watering. �Mulch clippings or leave them on the lawn. If necessary, dispose in a green waste container. �Cultivate your garden often to control weeds. Washing and Maintaining Your Car �Take your car to a commercial car wash whenever possible. �Choose soaps, cleaners, or detergents labeled “non-toxic,” “phosphate free” or “biodegradable.” Vegetable and citrus- based products are typically safest for the environment, but even these should not be allowed into the storm drain. �Shake floor mats into a trash can or vacuum to clean. �Do not use acid-based wheel cleaners and “hose off” engine degreasers at home. They can be used at a commercial facility, which can properly process the washwater. �Do not dump washwater onto your driveway, sidewalk, street, gutter or storm drain.Excess washwater should be disposed of in the sanitary sewers (through a sink, or toilet) or onto an absorbent surface like your lawn. �Use a nozzle to turn off water when not actively washing down automobile. �Monitor vehicles for leaks and place pans under leaks. Keep your car well maintained to stop and prevent leaks. �Use cat litter or other absorbents and sweep to remove any materials deposited by vehicles. Contain sweepings and dispose of at a HHWCC. �Perform automobile repair and maintenance under a covered area and use drip pans or plastic sheeting to keep spills and waste material from reaching storm drains. �Never pour oil or antifreeze in the street, gutter or storm drains. Recycle these substances at a service station, HHWCC, or used oil recycling center.For the nearest Used Oil Collection Center call 1-800-CLEANUP or visit www.ciwmb.ca.gov/UsedOil. Pollution Prevention Household Activities �Do not rinse spills with water!Sweep outdoor spills and dispose of in the trash. For wet spills like oil, apply cat litter or another absorbent material, then sweep and bring to a household hazardous waste collection center (HHWCC). �Securely cover trash cans. �Take household hazardous waste to a house- hold hazardous waste collection center. �Store household hazardous waste in closed, labeled containers inside or under a cover. �Do not hose down your driveway, sidewalk or patio. Sweep up debris and dispose of in trash. �Always pick up after your pet. Flush waste down the toilet or dispose of in the trash. �Bathe pets indoors or have them professionally groomed. Household Hazardous Wastes include: �Batteries �Paint thinners, paint strippers and removers �Adhesives �Drain openers �Oven cleaners �Wood and metal cleaners and polishes �Herbicides and pesticides �Fungicides/wood preservatives �Automotive fluids and products �Grease and rust solvents �Thermometers and other productscontaining mercury �Fluorescent lamps �Cathode ray tubes, e.g. TVs, computermonitors �Pool and spa chemicals For locations and hours of Household Hazardous Waste Collection Centers in Anaheim, Huntington Beach, Irvine and San Juan Capistrano, call (714)834-6752 or visit www.oclandfills.com. Ayude a prevenir la contaminación del océano Do your part to prevent water pollution in our creeks, rivers, bays and ocean. Clean beaches and healthy creeks, rivers, bays and ocean are important to Orange County. However, not properly disposing of household hazardous waste can lead to water pollution. Batteries, electronics, paint, oil, gardening chemicals, cleaners and other hazardous materials cannot be thrown in the trash. They also must never be poured or thrown into yards, sidewalks, driveways, gutters or streets. Rain or other water could wash the materials into the storm drain and eventually into our waterways and the ocean. In addition, hazardous waste must not be poured in the sanitary sewers (sinks and toilets). For more information, please call the Orange County Stormwater Program at 1-877-89-SPILL (1-877-897-7455) or visit www.ocwatersheds.com To Report Illegal Dumping of Household Hazardous Waste call 1-800-69-TOXIC To report a spill, call the Orange County 24-Hour Water Pollution Problem Reporting Hotline 1-877-89-SPILL (1-877-897-7455). For emergencies, dial 911. ORANGE COUNTY Help Prevent Ocean Pollution: Proper Disposal of Household Hazardous Waste The Ocean Begins at Your Front Door Printed on Recycled Paper NEVER DISPOSE OF HOUSEHOLD HAZARDOUS WASTE IN THE TRASH, STREET, GUTTER, STORM DRAIN OR SEWER. Pollution Prevention Leftover household products that contain corrosive, toxic, ignitable, or reactive ingredients are considered to be “household hazardous waste” or “HHW.” HHW can be found throughout your home, including the bathroom, kitchen, laundry room and garage. Disposal of HHW down the drain, on the ground, into storm drains, or in the trash is illegal and unsafe. Proper disposal of HHW is actually easy. Simply drop them off at a Household Hazardous Waste Collection Center (HHWCC) for free disposal and recycling. Many materials including anti-freeze, latex- based paint, motor oil and batteries can be recycled. Some centers have a “Stop & Swap” program that lets you take partially used home, garden, and automobile products free of charge. There are four HHWCCs in Orange County: Anaheim: ..................1071 N. Blue Gum St Huntington Beach: .........17121 Nichols St Irvine:............................ 6411 Oak Canyon San Juan Capistrano:...32250 La Pata Ave Centers are open Tuesday-Saturday, 9 a.m.- 3 p.m. Centers are closed on rainy days and major holidays. For more information, call (714) 834-6752 or visit www.oclandfills.com. Common household hazardous wastes Batteries Paint and paint products Adhesives Drain openers Household cleaning products Wood and metal cleaners and polishes Pesticides Fungicides/wood preservatives Automotive products (antifreeze, motor oil, fluids) Grease and rust solvents Fluorescent lamps Mercury (thermometers & thermostats) All forms of electronic waste including computers and microwaves Pool & spa chemicals Cleaners Medications Propane (camping & BBQ) Mercury-containing lamps Television & monitors (CRTs, flatscreens) Tips for household hazardous waste Never dispose of HHW in the trash, street, gutter, storm drain or sewer. Keep these materials in closed, labeled containers and store materials indoors or under a cover. When possible, use non-hazardous products. Reuse products whenever possible or share with family and friends. Purchase only as much of a product as you’ll need. Empty containers may be disposed of in the trash. HHW can be harmful to humans, pets and the environment. Report emergencies to 911. WHEN POSSIBLE, USE NON-HAZARDOUS OR LESS-HAZARDOUS PRODUCTS. Help Prevent Ocean Pollution: Recycle at Your Local Used Oil Collection Center CENTRAL COUNTY For more information, please call the Orange County Stormwater Program at 1-877-89-SPILL (1-877-897-7455) or visit www.watersheds.com. For information about the proper disposal of household hazardous waste, call the Household Waste Hotline at (714) 834-6752 or visit www.oclandfills.com. For additional information about the nearest oil recycling center, call the Used Oil Program at 1-800-CLEANUP or visit www.cleanup.org. Did you know that just one quart of oil can pollute 250,000 gallons of water? A clean ocean and healthy creeks, rivers, bays and beaches are important to Orange County. However, not properly disposing of used oil can lead to water pollution. If you pour or drain oil onto driveways, sidewalks or streets, it can be washed into the storm drain. Unlike water in sanitary sewers (from sinks and toilets), water in storm drains is not treated before entering the ocean. Help prevent water pollution by taking your used oil to a used oil collection center. Included in this brochure is a list of locations that will accept up to five gallons of used motor oil at no cost. Many also accept used oil filters. Please contact the facility before delivering your used oil. This listing of companies is for your reference and does not constitute a recommendation or endorsement of the company. Please note that used oil filters may not be disposed of with regular household trash. They must be taken to a household hazardous waste collection or recycling center in Anaheim, Huntington Beach, Irvine or San Juan Capistrano. For information about these centers, visit www.oclandfills.com. Please do not mix your oil with other substances! The Ocean Begins at Your Front Door DTP113 Rev 8/03 printed on recycled paper Used Oil Collection Centers This information was provided by the County of Orange Integrated Waste Management Department and the California Integrated Waste Management Board (CIWMB). Balboa Hill’s Boat Service 814 E Bay Ave., Balboa, CA 92661 (949)675-0740( ) CIWMB#: 30-C-03538 Balboa Island Island Marine Fuel 406 S Bay Front, Balboa Island, CA 92662 (949)673-1103( ) CIWMB#: 30-C-03728 Corona Del Mar Corona Del Mar 76 2201 E. Pacific Coast Hwy., Corona Del Mar, CA 92625 (949)673-3320( ) CIWMB#: 30-C-06620 Corona Del Mar Chevron 2546 E.Coast Hwy., Corona Del Mar, CA 92625 (949)495-0774(14) CIWMB#: 30-C-06424 Mobil (Harbor View) 2500 San Joaquin Hills Rd., Corona Del Mar,CA 92625 (949)640-4759( ) CIWMB#: 30-C-03363 Costa Mesa AutoZone #5520 744 W.19th St., Costa Mesa, CA 92627 (901)495-7159( ) CIWMB#: 30-C-05992 Big O Tires #5571 3181 Harbor Blvd., Costa Mesa, CA 92626 (949)443-4155( ) CIWMB#: 30-C-04676 Big O Tires #694 322 E. 17th St., Costa Mesa, CA 92627 (949)642-4131( ) CIWMB#: 30-C-05811 Coast General Performance 2855 Harbor Blvd., Costa Mesa, CA 92626 (714)540-5710( ) CIWMB#: 30-C-05916 Connell Chevrolet 2828 Harbor Blvd., Costa Mesa, CA 92626 (714)546-1200( ) CIWMB#: 30-C-06286 EZ Lube Inc #15 3599 Harbor Blvd., Costa Mesa, CA 92626 (714)966-1647( ) CIWMB#: 30-C-03137 EZ Lube Inc #46 400 E 17th St., Costa Mesa, CA 92627 (714)556-1312( ) CIWMB#: 30-C-05779 EZ Lube Inc. #44 2248 Harbor Blvd., Costa Mesa, CA 92627 (714)556-1312( ) CIWMB#: 30-C-05737 Firestone Store #71T7 475 E 17th St., Costa Mesa, CA 92627 (949)646-2444( ) CIWMB#: 30-C-02120 Jiffy Lube #1969 300 E 17th St., Costa Mesa, CA 92627 (949)548-2505( ) CIWMB#: 30-C-05553 Jiffy Lube #1970 2175 Newport Blvd., Costa Mesa, CA 92627 (949)548-4150( ) CIWMB#: 30-C-05554 Jiffy Lube #607 2255 Fairview Rd., Costa Mesa, CA 92627 (949)650-5823( ) CIWMB#: 30-C-05551 Jiffy Lube #861 375 Bristol St., Costa Mesa, CA 92626 (714)557-5823( ) CIWMB#: 30-C-05552 Kragen Auto Parts #0725 1739 Superior Ave., Costa Mesa, CA 92627 (949)642-3384( ) CIWMB#: 30-C-02624 Kragen Auto Parts #0796 1175 Baker Blvd., Unit E, Costa Mesa, CA 92626 (714)662-2005( ) CIWMB#: 30-C-02664 Nabers Cadillac 2600 Harbor Blvd., Costa Mesa, CA 92626 (714)444-5200( ) CIWMB#: 30-C-05051 Oil Stop Inc. Oil Stop Inc. Costa Mesa, CA 92626 (714)434-8350( ) CIWMB#: 30-C-06293 Pep Boys #660 2946 Bristol St., Costa Mesa, CA 92626 (714)549-1533( ) CIWMB#: 30-C-03416 Plaza Chevron Service Center 3048 Bristol Costa Mesa, CA 92626 (714)545-4257( ) CIWMB#: 30-C-01123 Scher Tire Inc #15 dba Goodyear Tire 1596 Newport Blvd., Costa Mesa, CA 92627 (949)548-9384( ) CIWMB#: 30-C-03034 Fountain Valley Firestone Store #7147 17975 Magnolia Ave., Fountain Valley, CA 92708 (714)842-3341( ) CIWMB#: 30-C-01219 Golden Shell 8520 Warner Ave., Fountain Valley, CA 92708 (714)842-7150( ) CIWMB#: 30-P-05002 Kragen Auto Parts #0734 9880 Warner Ave., Fountain Valley, CA 92708 (714)964-6427( ) CIWMB#: 30-C-02609 Kragen Auto Parts #1505 16147 Harbor Blvd., Fountain Valley, CA 92708 (714)531-8525( ) CIWMB#: 30-C-04125 Oil Can Henry's 9525 Warner Ave., Fountain Valley, CA 92708 (714)473-7705( ) CIWMB#: 30-C-05843 Purrfect Auto Service #10 16780 Harbor Blvd., Fountain Valley, CA 92708 (714)839-3899( ) CIWMB#: 30-C-01380 Huntington Beach AutoZone #5528 6800 Warner Ave., Huntington Beach, CA 92647 (714)891-8211( ) CIWMB#: 30-C-04777 Bella Terra Car Wash 16061 Beach Blvd., Huntington Beach, CA 92647 (714)847-4924( ) CIWMB#: 30-C-06195 Big O Tires #553 19411 Beach Blvd., Huntington Beach, CA 92648 (714)536-7571( ) CIWMB#: 30-C-00970 Econo Lube N' Tune #26 19961 Beach Blvd., Huntington Beach, CA 92648 (714)536-6519( ) CIWMB#: 30-C-06117 Expertec Automotive 7680 Talbert Ave Suite A& B, Huntington Beach, CA92648 (714)848-9222( ) CIWMB#: 30-C-05914 EZ Lube Inc #16 7361 Edinger Ave., Huntington Beach, CA 92647 (714)899-3600( ) CIWMB#: 30-C-03289 EZ Lube Inc. #79 9862 Adams St., Huntington Beach, CA 92647 (714)556-1312( ) CIWMB#: 30-C-06547 Firestone Store #71T5 16171 Beach Blvd., Huntington Beach, CA 92647 (714)847-6081( ) CIWMB#: 30-C-02118 Huntington Beach Car Wash 18971 Beach Blvd., Huntington Beach, CA 92648 (714)847-4924( ) CIWMB#: 30-C-05303 Jiffy Lube #1857 8971 Warner Ave., Huntington Beach, CA 92647 (714)596-7213( ) CIWMB#: 30-C-05053 Kragen Auto Parts #1468 10072 Adams Ave., Huntington Beach, CA 92646 (714)593-6156( ) CIWMB#: 30-C-04284 Kragen Auto Parts #1511 7171 Warner Ave., Huntington Beach, CA 92647 (714)842-4531( ) CIWMB#: 30-C-04129 Kragen Auto Parts #1633 18888 Beach Blvd., Huntington Beach, CA 92648 (714)965-2353( ) CIWMB#: 30-C-02645 Oilmax 10 Minute Lube/Wash 9862 Adams Ave., Huntington Beach, CA 92646 (714)964-7110( ) CIWMB#: 30-C-03219 Pep Boys #799 19122 Brookhurst St., Huntington Beach, CA 92646 (714)964-0777( ) CIWMB#: 30-C-03439 Quik Change Lube & Oil 5841 Warner Ave., Huntington Beach, CA 92649 (714)840-2331( ) CIWMB#: 30-C-03208 R Kids Tire and Service #6 5062 Warner Ave., Huntington Beach, CA 92647 (714)846-1189( ) CIWMB#: 30-C-05691 Saturn of Huntington Beach 18801 Beach Blvd., Huntington Beach, CA 92648 (714)841-5428( ) CIWMB#: 30-C-05221 USA Express Tire & Service Inc 7232 Edinger Ave., Huntington Beach, CA 92647 (714)842-0717( ) CIWMB#: 30-C-04429 Zito's Auto Care 19002 Magnolia St., Huntington Beach, CA 92646 (714)968-8788( ) CIWMB#: 30-C-03251 Irvine Firestone Store #71W4 51 Auto Center Dr., Irvine, CA 92618 (949)829-8710( ) CIWMB#: 30-C-03689 Irvine City Auto Parts 14427 Culver Dr., Irvine, CA 92604 (949)551-5588( ) CIWMB#: 30-C-02186 Jiffy Lube #1856 Irvine Spectrum 8777 Irvine Center Dr., Irvine, CA 92618 (949)753-0485( ) CIWMB#: 30-C-06094 Jiffy Lube #1988 3080 Main St., Irvine, CA 92614 (714)961-5491(27 ) CIWMB#: 30-C-04450 Kragen Auto Parts #4174 15315 Culver Dr., Ste.#170, Irvine, CA 92604 (602)631-7115( ) CIWMB#: 30-C-06417 Newport Beach Jiffy Lube #2811 1520 W Coast Hwy., Newport Beach, CA 92663 (949)764-9255( ) CIWMB#: 30-C-05629 Newport Landing Fuel Dock 503 E Edgewater Newport Beach, CA 92661 (949)673-7878( ) CIWMB#: 30-C-03628 Orange AutoZone #5942 1330 N. Glassell Orange, CA 92867 (714)538-4551( ) CIWMB#: 30-C-04553 Big O Tires #570 1825 E Katella Ave., Orange, CA 92867 (714)538-0016( ) CIWMB#: 30-C-00974 David Wilsons Ford of Orange 1350 W Katella Ave., Orange, CA 92867 (714)633-6731( ) CIWMB#: 30-C-02341 EZ Lube #74 3232 Chapman Ave. #E, Orange, CA 92869 (714)556-1312(106) CIWMB#: 30-C-06627 Firestone Store #7185 1690 N Tustin Ave., Orange, CA 92867 (714)282-8144( ) CIWMB#: 30-C-0122 Jiffy Lube #1457 433 W. Katella Ave., Orange, CA 92867 (714)720-5757( ) CIWMB#: 30-C-06280 Kragen Auto Parts #1764 910 Tustin St., Orange, CA 92867 (714)771-3000( ) CIWMB#: 30-C-02625 Managed Mobile, Inc. 1030 N Batavia St., #B, Orange, CA 92867 (714)400-0250( ) CIWMB#: 30-C-05776 Pep Boys #806 215 E Katella Ave., Orange, CA 92867 (714)997-1540( ) CIWMB#: 30-C-01759 Santiago Hills Car Care 8544 East Chapman Ave., Orange, CA 92869 (714)919-1060( ) CIWMB#: 30-C-05622 Scher Tire #33 1821 E. Katella Ave., Orange, CA 92867 (909)343-3100( ) CIWMB#: 30-C-06324 Tabassi Shell Service Station 830 E Katella Ave., Orange, CA 92867 (714)771-6990( ) CIWMB#: 30-C-00552 The Tune-up Center 193 S Main St., Orange, CA 92868 (714)633-1876( ) CIWMB#: 30-C-02091 Tony's Fuel and Towing 1650 W La Veta Ave., Orange, CA 92868 (714)953-7676( ) CIWMB#: 30-C-00868 Truck Lubrication Company 143 S. Pixley Orange, CA 92868 (714)997-7730( ) CIWMB#: 30-C-06001 Santa Ana All Phase Environmental 910 E. Fourth St., Santa Ana, CA 92701 (714)731-5995( ) CIWMB#: 30-C-06116 Archie's Tire & Towing 4518 Westminster Ave., Santa Ana, CA 92703 (714)636-4518( ) CIWMB#: 30-C-02058 AutoZone #3320 2007 S. Main St., Santa Ana, CA 92707 (901)495-7217( ) CIWMB#: 30-C-06508 AutoZone #5232 430 W 17th Santa Ana, CA 92706 (714)547-7003( ) CIWMB#: 30-C-04609 AutoZone #5538 1101 S Bristol Santa Ana, CA 92704 (714)241-0335( ) CIWMB#: 30-C-00829 Big O Tires 1211 W. Warner Ave., Santa Ana, CA 92707 (714)540-8646( ) CIWMB#: 30-C-04679 Big O Tires #712 1302 E. 17th St., Santa Ana, CA 92705 (714)541-6811( ) CIWMB#: 30-C-05813 Firestone Store #7175 3733 S Bristol Santa Ana, CA 92704 (714)549-4015( ) CIWMB#: 30-C-01223 Firestone Store #71TA 101 S Main St., Santa Ana, CA 92701 (714)542-8857( ) CIWMB#: 30-C-02123 Firestone Store #71W6 2005 N Tustin Ave., Ste A, Santa Ana, CA 92705 (714)541-7977( ) CIWMB#: 30-C-03688 Guaranty Chevrolet Motors Inc. 711 E 17th St., Santa Ana, CA 92701 (714)973-1711(277 ) CIWMB#: 30-C-06506 Jiffy Lube #1303 2025 N. Tustin Santa Ana, CA 92701 (714)720-5757( ) CIWMB#: 30-C-06283 John's Mobil 1465 S Main St., Santa Ana, CA 92707 (714)835-3266( ) CIWMB#: 30-C-00578 Kragen Auto Parts #0736 1302 E 17th St., Santa Ana, CA 92705 (714)953-6061( ) CIWMB#: 30-C-02610 Kragen Auto Parts #1253 1400 W Edinger Ave., Santa Ana, CA 92704 (714)754-1432( ) CIWMB#: 30-C-02627 Kragen Auto Parts #1376 521 W 17th St., Santa Ana, CA 92706 (714)543-4492( ) CIWMB#: 30-C-03901 Kragen Auto Parts #1516 2337 S Bristol Ave., Santa Ana, CA 92704 (714)557-0787( ) CIWMB#: 30-C-04106 Kragen Auto Parts #1648 1015 S Main St., Santa Ana, CA 92701 (714)568-1570( ) CIWMB#: 30-C-05664 Pep Boys #609 120 E 1st St., Santa Ana, CA 92701 (714)547-7477( ) CIWMB#: 30-C-01738 Pep Boys #802 1107 S Harbor Blvd., Santa Ana, CA 92704 (714)775-0828( ) CIWMB#: 30-C-01739 Purrfect Auto Service 2519 S Main St., Santa Ana, CA 92707 (714)549-7900( ) CIWMB#: 30-C-02085 Saturn of Santa Ana 1350 Auto Mall Dr., Santa Ana, CA 92705 (714)648-2444( ) CIWMB#: 30-C-05222 Scher Tire #28 1805 N Grand Ave., Santa Ana, CA 92705 (714)558-8644( ) CIWMB#: 30-C-03225 Tustin Big O Tires #555 131 E 1st St., Tustin, CA 92780 (714)544-9431( ) CIWMB#: 30-C-00972 EZ Lube #42 12972 Newport Ave., Tustin, CA 92780 (714)556-1312( ) CIWMB#: 30-C-06408 Jiffy Lube #1406 3087 Edinger Ave., Tustin, CA 92780 (949)651-8814( ) CIWMB#: 30-C-03778 Kragen Auto Parts #1533 502 B E 1st St., Tustin, CA 92780 (714)544-9249( ) CIWMB#: 30-C-04128 Scher Tire Inc #17 dba Goodyear Tire 14511 Redhill Ave., Tustin, CA 92780 (714)832-6011( ) CIWMB#: 30-C-03035 Villa Park Phil’s Villa Park 76 17771 Santiago Blvd., Villa Park, CA 92861 (714)637-0854( ) CIWMB#: 30-C-06579 For more information, please call the Orange County Stormwater Program at 1-877-89-SPILL (1-877-897-7455) or visit www.ocwatersheds.com UCCE Master Gardener Hotline: (714) 708-1646 To report a spill, call the Orange County 24-Hour Water Pollution Problem Reporting Hotline 1-877-89-SPILL (1-877-897-7455). For emergencies, dial 911. The tips contained in this brochure provide useful information to help prevent water pollution while landscaping or gardening. If you have other suggestions, please contact your city’s stormwater representatives or call the Orange County Stormwater Program. C lean beaches and healthy creeks, rivers, bays and ocean are important to Orange County. However, many common activities can lead to water pollution if you’re not careful. Fertilizers, pesticides and other chemicals that are left on yards or driveways can be blown or washed into storm drains that flow to the ocean. Overwatering lawns can also send materials into storm drains. Unlike water in sanitary sewers (from sinks and toilets), water in storm drains is not treated before entering our waterways. You would never pour gardening products into the ocean, so don’t let them enter the storm drains. Follow these easy tips to help prevent water pollution. Printed on Recycled Paper Tips for Landscape and GardeningTips for Landscape & Gardening Never allow gardening products or polluted water to enter the street, gutter or storm drain. General Landscaping Tips Protect stockpiles and materials from wind and rain by storing them under tarps or secured plastic sheeting. Prevent erosion of slopes by planting fast-growing, dense ground covering plants. These will shield and bind the soil. Plant native vegetation to reduce the amount of water, fertilizers, and pesticide applied to the landscape. Never apply pesticides or fertilizers when rain is predicted within the next 48 hours. Garden & Lawn Maintenance Do not overwater. Use irrigation practices such as drip irrigation, soaker hoses or micro spray systems. Periodically inspect and fix leaks and misdirected sprinklers. Do not rake or blow leaves, clippings or pruning waste into the street, gutter or storm drain. Instead, dispose of green waste by composting, hauling it to a permitted landfill, or recycling it through your city’s program. Use slow-release fertilizers to minimize leaching, and use organic fertilizers. Read labels and use only as directed. Do not over-apply pesticides or fertilizers. Apply to spots as needed, rather than blanketing an entire area. Store pesticides, fertilizers and other chemicals in a dry covered area to prevent exposure that may result in the deterioration of containers and packaging. Rinse empty pesticide containers and re-use rinse water as you would use the product. Do not dump rinse water down storm drains. Dispose of empty containers in the trash. When available, use non-toxic alternatives to traditional pesticides, and use pesticides specifically designed to control the pest you are targeting. For more information, visit www.ipm.ucdavis.edu. If fertilizer is spilled, sweep up the spill before irrigating. If the spill is liquid, apply an absorbent material such as cat litter, and then sweep it up and dispose of it in the trash. Take unwanted pesticides to a Household Hazardous Waste Collection Center to be recycled. Locations are provided below. Household Hazardous Waste Collection Centers Anaheim: 1071 N. Blue Gum St. Huntington Beach: 17121 Nichols St. Irvine: 6411 Oak Canyon San Juan Capistrano: 32250 La Pata Ave. For more information, call (714) 834-6752 or visit www.oclandfills.com C lean beaches and healthy creeks, rivers, bays and ocean are important to Orange County. However, many common activities can lead to water pollution if you’re not careful. Pet waste and pet care products can be washed into the storm drains that flow to the ocean. Unlike water in sanitary sewers (from sinks and toilets), water in storm drains is not treated before entering our waterways. You would never put pet waste or pet care products into the ocean, so don’t let them enter the storm drains. Follow these easy tips to help prevent water pollution. For more information, please call the Orange County Stormwater Program at 1-877-89-SPILL (1-877-897-7455) or visit www.ocwatersheds.com To report a spill, call the Orange County 24-Hour Water Pollution Problem Reporting Hotline 1-877-89-SPILL (1-877-897-7455). For emergencies, dial 911. The tips contained in this brochure provide useful information to help prevent water pollution while caring for your pet. If you have other suggestions, please contact your city’s stormwater representatives or call the Orange County Stormwater Program. Printed on Recycled Paper Never let any pet care products or washwater run off your yard and into the street, gutter or storm drain. Washing Your Pets Even biodegradable soaps and shampoos can be harmful to marine life and the environment. If possible, bathe your pets indoors using less-toxic shampoos or have your pet professionally groomed. Follow instructions on the products and clean up spills. If you bathe your pet outside, wash it on your lawn or another absorbent/ permeable surface to keep the washwater from running into the street, gutter or storm drain. Flea Control Consider using oral or topical flea control products. If you use flea control products such as shampoos, sprays or collars, make sure to dispose of any unused products at a Household Hazardous Waste Collection Center. For location information, call (714) 834-6752. Why You Should Pick Up After Your Pet It’s the law! Every city has an ordinance requiring you to pick up after your pet. Besides being a nuisance, pet waste can lead to water pollution, even if you live inland. During rainfall, pet waste left outdoors can wash into storm drains. This waste flows directly into our waterways and the ocean where it can harm human health, marine life and the environment. As it decomposes, pet waste demands a high level of oxygen from water. This decomposition can contribute to killing marine life by reducing the amount of dissolved oxygen available to them. Have fun with your pets, but please be a responsible pet owner by taking care of them and the environment. Take a bag with you on walks to pick up after your pet. Dispose of the waste in the trash or in a toilet. Tips for Pet Care Help Prevent Ocean Pollution: For more information, please call the Orange County Stormwater Program at 1-877-89-SPILL (1-877-897-7455) or visit www.ocwatersheds.com To report a spill, call the Orange County 24-Hour Water Pollution Problem Reporting Hotline at 1-877-89-SPILL (1-877-897-7455). For emergencies, dial 911. The tips contained in this brochure provide useful information to help prevent water pollution. If you have other suggestions, please contact your city’s stormwater representatives or call the Orange County Stormwater Program. Printed on Recycled Paper Tips for Residential Pool, Landscape and Hardscape Drains Pool Maintenance All pool water discharged to the curb, gutter or permitted pool drain from your property must meet the following water quality criteria: The residual chlorine does not exceed 0.1 mg/L (parts per million). The pH is between 6.5 and 8.5. The water is free of any unusual coloration. There is no discharge of filter media or acid cleaning wastes. Some cities have ordinances that do not allow pool water to be discharged to the storm drain. Check with your city. Landscape and Hardscape Drains The following recommendations will help reduce or prevent pollutants from your landscape and hardscape drains from entering the street, gutter or storm drain. Unlike water that enters the sewer (from sinks and toilets), water that enters a landscape or hardscape drain is not treated before entering our creeks, rivers, bays and ocean. Household Activities Do not rinse spills of materials or chemicals to any drain. Use dry cleanup methods such as applying cat litter or another absorbent material, then sweep it up and dispose of it in the trash. If the material is hazardous, dispose of it at a Household Hazardous Waste Collection Center (HHWCC). For locations, call (714) 834-6752 or visit www.oclandfills.com. Do not hose down your driveways, sidewalks or patios to your landscape or hardscape drain. Sweep up debris and dispose of it in the trash. Always pick up after your pet. Flush waste down the toilet or dispose of it in the trash. Tips for Residential Pool, Landscape and Hardscape Drains Do not store items such as cleaners, batteries, automotive fluids, paint products, TVs, or computer monitors uncovered outdoors. Take them to a HHWCC for disposal. Yard Maintenance Do not overwater. Water by hand or set automated irrigation systems to reflect seasonal water needs. Follow directions on pesticides and fertilizers (measure, do not estimate amounts) and do not use if rain is predicted within 48 hours. Cultivate your garden often to control weeds and reduce the need to use chemicals. Vehicle Maintenance Never pour oil or antifreeze down your landscape or hardscape drain. Recycle these substances at a service station, a waste collection center or used oil recycling center. For locations, contact the Used Oil Program at 1-800- CLEANUP or visit www.CLEANUP.org. Whenever possible, take your vehicle to a commercial car wash. If you do wash your vehicle at home, do not allow the washwater to go down your landscape or hardscape drain. Instead, dispose of it in the sanitary sewer (a sink or toilet) or onto an absorbent surface such as your lawn. Use a spray nozzle that will shut off the water when not in use. APPENDIX C BMP DETAILS / SUPPORTING CALCULATIONS TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-28 December 20, 2013 INF-3: Bioretention with no Underdrain Bioretention stormwater treatment facilities are landscaped shallow depressions that capture and filter stormwater runoff. These facilities function as a soil and plant-based filtration device that removes pollutants through a variety of physical, biological, and chemical treatment processes. The facilities normally consist of a ponding area, mulch layer, planting soils, and plants. As stormwater passes down through the planting soil, pollutants are filtered, adsorbed, and biodegraded by the soil and plants. For areas with low permeability native soils or steep slopes, bioretention areas can be designed with an underdrain system that routes the treated runoff to the storm drain system rather than depending entirely on infiltration. Feasibility Screening Considerations x Bioretention with no underdrains shall pass infiltration infeasibility screening criteria to be considered for use. Opportunity Criteria x Land use may include commercial, residential, mixed use, institutional, and subdivisions. Bioretention may also be applied in parking lot islands, cul-de-sacs, traffic circles, road shoulders, and road medians. x Drainage area is ≤ 5 acres, preferrably ≤ 1 acre. x Area available for infiltration. x Soils are adequate for infiltration or can be amended to improve infiltration capacity. Site slope is less than 15 percent. OC-Specific Design Criteria and Considerations □ Placement of BMPs should observe geotechnical recommendations with respect to geological hazards (e.g. landslides, liquefaction zones, erosion, etc.) and set -backs (e.g., foundations, utilities, roadways, etc.) □ Depth to mounded seasonally high groundwater shall not be less than 5 feet. □ If sheet flow is conveyed to the treatment area over stabilized grassed areas, the site must be graded in such a way that minimizes erosive conditions; sheet flow velocities should not exceed 1 foot per second. □ Ponding depth should not exceed 18 inches; fencing may be required if ponding depth exceeds 6 inches to mitigate the risk of drowning. □ Planting/storage media shall be based on the recommendations contained in MISC-1: Planting/Storage Media □ The minimum amended soil depth is 1.5 feet (3 feet is preferred). □ The maximum drawdown time of the planting soil is 48 hours. Also known as: ¾Rain gardens ¾Infiltration planter Bioretention Source: Geosyntec Consultants TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-29 December 20, 2013 □ Infiltration pathways may need to be restricted due to the close proximity of roads, foundations, or other infrastructure. A geomembrane liner, or other equivalent water proofing, may be placed along the vertical walls to reduce lateral flows. This liner should have a minimum thickness of 30 mils. □ Plant materials should be tolerant of summer drought, ponding fluctuations, and saturated soil conditions for 48 hours; native plant species and/or hardy cultivars that are not invasive and do not require chemical fertilizers or pesticides should be used to the maximum extent feasible. □ The bioretention area should be covered with 2-4 inches (average 3 inches) of mulch at startup and an additional placement of 1-2 inches of mulch should be added annually. □ An optional gravel drainage layer may be installed below planting media to augment storage volume. □ An overflow device is required at the top of the ponding depth. □ Dispersed flow or energy dissipation (i.e. splash rocks) for piped inlets should be provided at basin inlet to prevent erosion. Simple Sizing Method for Bioretention with no Underdrain If the Simple Design Capture Volume Sizing Method described in Appendix III.3.1 is used to size a bioretention area with underdrains, the user calculates the DCV and designs the system with geometry required to draw down the DCV in 48 hours. The sizing steps are as follows: Step 1: Determine the Bioretention Design Capture Volume Calculate the DCV using the Simple Design Capture Volume Sizing Method described in Appendix III.3.1. Step 2: Determine the 48-hour Ponding Depth The depth of effective storage depth that can be drawn down in 48 hours can be calculated using the following equation: d48 = KDESIGN × 4 Where: d48 = bioretention 48-hour effective depth, ft KDESIGN = bioretention design infiltration rate, in/hr (See Appendix VII) This is the maximum effective depth of the basin below the overflow device to achieve drawdown in 48 hours. Effective depth includes ponding water and media/aggregate pore space. Step 3: Design System Geometry to Provide d48 Design system geometry such that d48 ≥ dEFFECTIVE = (dP + nMdM + nGdG) Where: d48 = depth of water that can drain in 48 hours dEFFECTIVE = total effective depth of water stored in bioretention area, ft dP = bioretention ponding depth, ft (should be less than or equal to 1.5 ft) nM = bioretention media porosity dM = bioretention media depth, ft TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-30 December 20, 2013 nG = bioretention gravel layer porosity; 0.35 may be assumed where other information is not available dG = bioretention gravel layer depth, ft Step 4: Calculate the Required Infiltrating Area The required infiltrating area (i.e. measured at the media surface) can be calculated using the following equation: A = DCV / dEFFECTIVE Where: A = required infiltrating area, sq-ft (measured as the media surface area) DCV = design capture volume, cu-ft (see Step 1) dEFFECTIVE = total effective depth of water stored in bioretention area, ft (from Step 3) This does not include the side slopes, access roads, etc. which would increase bioretention footprint. Capture Efficiency Method for Bioretention with no Underdrain If BMP geometry has already been defined and deviates from the 48 hour drawdown time, the designer can use the Capture Efficiency Method for Volume-Based, Constant Drawdown BMPs (See Appendix III.3.2) to determine the fraction of the DCV that must be provided to manage 80 percent of average annual runoff volume. This method accounts for drawdown time different than 48 hours. Step 1: Determine the drawdown time associated with the selected basin geometry DD = (dEFFECTIVE / KDESIGN) × 12 in/ft Where: DD = time to completely drain infiltration basin ponding depth, hours dEFFECTIVE ≤ (dP + nMdM + nGdG) dP = bioretention ponding depth, ft (should be less than or equal to 1.5 ft) nM = bioretention media porosity dM = bioretention media depth, ft nG = bioretention gravel layer porosity; 0.35 may be assumed where other information is not available dG = bioretention gravel layer depth, ft KDESIGN = basin design infiltration rate, in/hr (See Appendix VII) Step 2: Determine the Required Adjusted DCV for this Drawdown Time Use the Capture Efficiency Method for Volume-Based, Constant Drawdown BMPs (See Appendix III.3.2) to calculate the fraction of the DCV the basin must hold to achieve 80 percent capture of average annual stormwater runoff volume based on the basin drawdown time calculated above. Step 4: Check that the Bioretention Effective Depth Drains in no Greater than 96 Hours DD = (dEFFECTIVE / KDESIGN) × 12 Where: DD = time to completely drain bioretention facility, hours dEFFECTIVE = total effective depth of water stored in bioretention area, ft (from Step 3) KDESIGN = basin design infiltration rate, in/hr (See Appendix VII) TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-31 December 20, 2013 If DDALL is greater than 96 hours, adjust bioretention media depth and/or gravel layer depth until DD is less than 96 hours. This duration is based on preventing extended periods of saturation from causing plant mortality. Step 5: Determine the Basin Infiltrating Area Needed The required infiltrating area (i.e. the surface area of the top of the media layer) can be calculated using the following equation: A = DCV/ dEFFECTIVE Where: A = required infiltrating area, sq-ft (measured at the media surface) DCV = design capture volume, adjusted for drawdown time, cu-ft (see Step 1) dEFFECTIVE = total effective depth of water stored in bioretention area, ft (from Step 3) This does not include the side slopes, access roads, etc. which would increase bioretention footprint. If the area required is greater than the selected basin area, adjust surface area or adjust ponding depth and recalculate required area until the required area is achieved. Configuration for Use in a Treatment Train x Bioretention areas may be preceeded in a treatment train by HSCs in the drainage area, which would reduce the required volume of the bioretention cell. x Bioretention areas can be incorporated in a treatment train to provide enhanced water quality treatment and reductions in runoff volume and rate. For example, runoff can be collected from a roadway in a vegetated swale that then flows to a bioretention area. Similarly, bioretention could be used to manage overflow from a cistern. Additional References for Design Guidance x CASQA BMP Handbook for New and Redevelopment: http://www.cabmphandbooks.com/Documents/Development/TC-32.pdf x SMC LID Manual (pp 68): http://www.lowimpactdevelopment.org/guest75/pub/All_Projects/SoCal_LID_Manual/SoCalL ID_Manual_FINAL_040910.pdf x Los Angeles County Stormwater BMP Design and Maintenance Manual, Chapter 5: http://dpw.lacounty.gov/DES/design_manuals/StormwaterBMPDesignandMaintenance.pdf x San Diego County LID Handbook Appendix 4 (Factsheet 7): http://www.sdcounty.ca.gov/dplu/docs/LID-Appendices.pdf x Los Angeles Unified School District (LAUSD) Stormwater Technical Manual, Chapter 4. http://www.laschools.org/employee/design/fs-studies-and- reports/download/white_paper_report_material/Storm_Water_Technical_Manual_2009-opt- red.pdf?version_id=76975850 County of Los Angeles Low Impact Development Standards Manual, Chapter 5: http://dpw.lacounty.gov/wmd/LA_County_LID_Manual.pdf MWS Linear Advanced Stormwater Biofiltration Contents 1 Introduction 2 Applications 3 Configurations 4 Advantages 5 Operation 6 Orientations | Bypass 7 Performance | Approvals 8 Sizing 9 Installation | Maintenance | Plants www.ModularWetlands.com The Urban Impact For hundreds of years natural wetlands surrounding our shores have played an integral role as nature’s stormwater treatment system. But as our cities grow and develop, these natural wetlands have perished under countless roads, rooftops, and parking lots. Plant A Wetland Without natural wetlands our cities are deprived of water purification, flood control, and land stability. Modular Wetlands and the MWS Linear re-establish nature’s presence and rejuvenate water ways in urban areas. MWS Linear The Modular Wetland System Linear represents a pioneering breakthrough in stormwater technology as the only biofiltration system to utilize patented horizontal flow, allowing for a smaller footprint and higher treatment capacity. While most biofilters use little or no pre- treatment, the MWS Linear incorporates an advanced pre-treatment chamber that includes separation and pre-filter cartridges. In this chamber sediment and hydrocarbons are removed from runoff before it enters the biofiltration chamber, in turn reducing maintenance costs and improving performance. Parking Lots Parking lots are designed to maximize space and the MWS Linear’s 4 ft. standard planter width allows for easy integration into parking lot islands and other landscape medians. Mixed Use The MWS Linear can be installed as a raised planter to treat runoff from rooftops or patios, making it perfect for sustainable “live-work” spaces. Industrial Many states enforce strict regulations for discharges from industrial sites. The MWS Linear has helped various sites meet difficult EPA mandated effluent limits for dissolved metals and other pollutants. Residential Low to high density developments can benefit from the versatile design of the MWS Linear. The system can be used in both decentralized LID design and cost-effective end-of-the-line configurations. Streets Street applications can be challenging due to limited space. The MWS Linear is very adaptable, and offers the smallest footprint to work around the constraints of existing utilities on retrofit projects. Commercial Compared to bioretention systems, the MWS Linear can treat far more area in less space - meeting treatment and volume control requirements. Applications The MWS Linear has been successfully used on numerous new construction and retrofit projects. The system’s superior versatility makes it beneficial for a wide range of stormwater and waste water applications - treating rooftops, streetscapes, parking lots, and industrial sites. More applications are available on our website: www.ModularWetlands.com/Applications • Agriculture • Reuse • Low Impact Development • Waste Water www.ModularWetlands.com | Page 3 Configurations The MWS Linear is the preferred biofiltration system of Civil Engineers across the country due to its versatile design. This highly versatile system has available “pipe-in” options on most models, along with built-in curb or grated inlets for simple integration into your stormdrain design. Curb Type The Curb Type configuration accepts sheet flow through a curb opening and is commonly used along road ways and parking lots. It can be used in sump or flow by conditions. Length of curb opening varies based on model and size. Grate Type The Grate Type configuration offers the same features and benefits as the Curb Type but with a grated/drop inlet above the systems pre-treatment chamber. It has the added benefit of allowing for pedestrian access over the inlet. ADA compliant grates are available to assure easy and safe access. The Grate Type can also be used in scenarios where runoff needs to be intercepted on both sides of landscape islands. Downspout Type The Downspout Type is a variation of the Vault Type and is designed to accept a vertical downspout pipe from roof top and podium areas. Some models have the option of utilizing an internal bypass, simplifying the overall design. The system can be installed as a raised planter and the exterior can be stuccoed or covered with other finishes to match the look of adjacent buildings. Vault Type The system’s patented horizontal flow biofilter is able to accept inflow pipes directly into the pre-treatment chamber, meaning the MWS Linear can be used in end-of-the-line installations. This greatly improves feasibility over typical decentralized designs that are required with other biofiltration/bioretention systems. Another benefit of the “pipe in” design is the ability to install the system downstream of underground detention systems to meet water quality volume requirements. Cartridge Housing Pre-filter Cartridge Curb Inlet Individual Media Filters Advantages & Operation The MWS Linear is the most efficient and versatile biofiltration system on the market, and the only system with horizontal flow which improves performance, reduces footprint, and minimizes maintenance. Figure-1 and Figure-2 illustrate the invaluable benefits of horizontal flow and the multiple treatment stages. • Horizontal Flow Biofiltration • Greater Filter Surface Area • Pre-Treatment Chamber • Patented Perimeter Void Area • Flow Control • No Depressed Planter Area Separation • Trash, sediment, and debris are separated before entering the pre-filter cartridges • Designed for easy maintenance access Pre-Filter Cartridges • Over 25 ft2 of surface area per cartridge • Utilizes BioMediaGREEN filter material • Removes over 80% of TSS & 90% of hydrocarbons • Prevents pollutants that cause clogging from migrating to the biofiltration chamber Pre-Treatment1 1 2 Drain-Down Line 1 2Vertical Underdrain Manifold Featured Advantages www.ModularWetlands.com | Page 5 Fig. 1 Horizontal Flow • Less clogging than downward flow biofilters • Water flow is subsurface • Improves biological filtration Patented Perimeter Void Area • Vertically extends void area between the walls and the WetlandMEDIA on all four sides. • Maximizes surface area of the media for higher treatment capacity WetlandMEDIA • Contains no organics and removes phosphorus • Greater surface area and 48% void space • Maximum evapotranspiration • High ion exchange capacity and light weight Flow Control • Orifice plate controls flow of water through WetlandMEDIA to a level lower than the media’s capacity. • Extends the life of the media and improves performance Drain-Down Filter • The Drain-Down is an optional feature that completely drains the pre-treatment chamber • Water that drains from the pre-treatment chamber between storm events will be treated 2x to 3x More Surface Area Than Traditional Downward Flow Bioretention Systems.Fig. 2 - Top View Biofiltration2 Discharge3 Perimeter Voi d A r e a 3 4 3Flow Control Riser Drain-Down Line Outlet Pipe Orientations Bypass Internal Bypass Weir (Side-by-Side Only) The Side-By-Side orientation places the pre- treatment and discharge chambers adjacent to one another allowing for integration of internal bypass. The wall between these chambers can act as a bypass weir when flows exceed the system’s treatment capacity, thus allowing bypass from the pre-treatment chamber directly to the discharge chamber. External Diversion Weir Structure This traditional offline diversion method can be used with the MWS Linear in scenarios where runoff is being piped to the system. These simple and effective structures are generally configured with two outflow pipes. The first is a smaller pipe on the upstream side of the diversion weir - to divert low flows over to the MWS Linear for treatment. The second is the main pipe that receives water once the system has exceeded treatment capacity and water flows over the weir. Flow By Design This method is one in which the system is placed just upstream of a standard curb or grate inlet to intercept the first flush. Higher flows simply pass by the MWS Linear and into the standard inlet downstream. End-To-End The End-To-End orientation places the pre-treatment and discharge chambers on opposite ends of the biofiltration chamber therefore minimizing the width of the system to 5 ft (outside dimension). This orientation is perfect for linear projects and street retrofits where existing utilities and sidewalks limit the amount of space available for installation. One limitation of this orientation is bypass must be external. Side-By-Side The Side-By-Side orientation places the pre- treatment and discharge chamber adjacent to one another with the biofiltration chamber running parallel on either side. This minimizes the system length, providing a highly compact footprint. It has been proven useful in situations such as streets with directly adjacent sidewalks, as half of the system can be placed under that sidewalk. This orientation also offers internal bypass options as discussed below. This simple yet innovative diversion trough can be installed in existing or new curb and grate inlets to divert the first flush to the MWS Linear via pipe. It works similar to a rain gutter and is installed just below the opening into the inlet. It captures the low flows and channels them over to a connecting pipe exiting out the wall of the inlet and leading to the MWS Linear. The DVERT is perfect for retrofit and green street applications that allows the MWS Linear to be installed anywhere space is available. DVERT Low Flow Diversion DVERT Trough www.ModularWetlands.com | Page 7 Rhode Island DEM Approved Approved as an authorized BMP and noted to achieve the following minimum removal efficiencies: 85% TSS, 60% Pathogens, 30% Total Phosphorus, and 30% Total Nitrogen. MASTEP Evaluation The University of Massachusetts at Amherst – Water Resources Research Center, issued a technical evaluation report noting removal rates up to 84% TSS, 70% Total Phosphorus, 68.5% Total Zinc, and more. Maryland Department Of The Environment Approved Granted ESD (Environmental Site Design) status for new construction, redevelopment and retrofitting when designed in accordance with the Design Manual. Washington State TAPE Approved The MWS Linear is approved for General Use Level Designation (GULD) for Basic, Enhanced, and Phosphorus treatment at 1 gpm/ft2 loading rate. The highest performing BMP on the market for all main pollutant categories. Approvals The MWS Linear has successfully met years of challenging technical reviews and testing from some of the most prestigious and demanding agencies in the nation, and perhaps the world. DEQ Assignment The Virginia Department of Environmental Quality assigned the MWS Linear, the highest phosphorus removal rating for manufactured treatment devices to meet the new Virginia Stormwater Management Program (VSMP) Technical Criteria. VA TSS Total Phosphorus Ortho Phosphorus Nitrogen Dissolved Zinc Dissolved Copper Total Zinc Total Copper Motor Oil 85%64%67%45%66%38%69%50%95% Performance The MWS Linear continues to outperform other treatment methods with superior pollutant removal for TSS, heavy metals, nutrients, hydrocarbons and bacteria. Since 2007 the MWS Linear has been field tested on numerous sites across the country. With it’s advanced pre-treatment chamber and innovative horizontal flow biofilter, the system is able to effectively remove pollutants through a combination of physical, chemical, and biological filtration processes. With the same biological processes found in natural wetlands, the MWS Linear harnesses natures ability to process, transform, and remove even the most harmful pollutants. Treatment Flow Sizing Table Model #Dimensions WetlandMedia Surface Area Treatment Flow Rate (cfs) MWS-L-4-4 4’ x 4’23 ft2 0.052 MWS-L-4-6 4’ x 6’32 ft2 0.073 MWS-L-4-8 4’ x 8’50 ft2 0.115 MWS-L-4-13 4’ x 13’63 ft2 0.144 MWS-L-4-15 4’ x 15’76 ft2 0.175 MWS-L-4-17 4’ x 17’90 ft2 0.206 MWS-L-4-19 4’ x 19’103 ft2 0.237 MWS-L-4-21 4’ x 21’117 ft2 0.268 MWS-L-8-8 8’ x 8’100 ft2 0.230 MWS-L-8-12 8’ x 12’151 ft2 0.346 MWS-L-8-16 8’ x 16’201 ft2 0.462 Flow Based Sizing The MWS Linear can be used in stand alone applications to meet treatment flow requirements. Since the MWS Linear is the only biofiltration system that can accept inflow pipes several feet below the surface it can be used not only in decentralized design applications but also as a large central end-of-the-line application for maximum feasibility. Volume Based Sizing Many states require treatment of a water quality volume and do not offer the option of flow based design. The MWS Linear and its unique horizontal flow makes it the only biofilter that can be used in volume based design installed downstream of ponds, detention basins, and underground storage systems. Treatment Volume Sizing Table Model #Treatment Capacity (cu. ft.) @ 24-Hour Drain Down Treatment Capacity (cu. ft.) @ 48-Hour Drain Down MWS-L-4-4 1140 2280 MWS-L-4-6 1600 3200 MWS-L-4-8 2518 5036 MWS-L-4-13 3131 6261 MWS-L-4-15 3811 7623 MWS-L-4-17 4492 8984 MWS-L-4-19 5172 10345 MWS-L-4-21 5853 11706 MWS-L-8-8 5036 10072 MWS-L-8-12 7554 15109 MWS-L-8-16 10073 20145 www.ModularWetlands.com | Page 9 Installation The MWS Linear is simple, easy to install, and has a space efficient design that offers lower excavation and installation costs compared to traditional tree-box type systems. The structure of the system resembles pre- cast catch basin or utility vaults and is installed in a similar fashion. The system is delivered fully assembled for quick installation. Generally, the structure can be unloaded and set in place in 15 minutes. Our experienced team of field technicians are available to supervise installations and provide technical support. Plant Selection Abundant plants, trees, and grasses bring value and an aesthetic benefit to any urban setting, but those in the MWS Linear do even more - they increase pollutant removal. What’s not seen, but very important, is that below grade the stormwater runoff/flow is being subjected to nature’s secret weapon: a dynamic physical, chemical, and biological process working to break down and remove non-point source pollutants. The flow rate is controlled in the MWS Linear, giving the plants more “contact time” so that pollutants are more successfully decomposed, volatilized and incorporated into the biomass of The MWS Linear’s micro/macro flora and fauna. A wide range of plants are suitable for use in the MWS Linear, but selections vary by location and climate. View suitable plants by selecting the list relative to your project location’s hardy zone. Please visit www.ModularWetlands.com/Plants for more information and various plant lists. Maintenance Reduce your maintenance costs, man hours, and materials with the MWS Linear. Unlike other biofiltration systems that provide no pre-treatment, the MWS Linear is a self-contained treatment train which incorporates simple and effective pre-treatment. Maintenance requirements for the biofilter itself are almost completely eliminated, as the pre-treatment chamber removes and isolates trash, sediments, and hydrocarbons. What’s left is the simple maintenance of an easily accessible pre-treatment chamber that can be cleaned by hand or with a standard vac truck. Only periodic replacement of low-cost media in the pre-filter cartridges is required for long term operation and there is absolutely no need to replace expensive biofiltration media. © Modular Wetland Systems, Inc. www.ModularWetlands.com | (855) 5MOD-WET | info@ModularWetlands.com APPENDIX D BMP MAINTENANCE SUPPLEMENT / O&M PLAN OPERATIONS AND MAINTENANCE (O&M) PLAN Water Quality Management Plan For Tentative Tract No. 17847 Nicky Way and Santiago Canyon Road APN 379-451-24 This page intentionally left blank OPERATIONS AND MAINTENANCE PLAN Page 3 of 12 BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Applicable? Yes/No BMP Name and BMP Implementation, Maintenance and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility NON-STRUCTURAL SOURCE CONTROL BMPs Yes N3. Common Area Landscape Management Maintenance shall be consistent with City requirements. Fertilizer and/or pesticide usage shall be consistent with County Management Guidelines for Use of Fertilizers (OC DAMP Section 5.5) as well as local requirements. Maintenance includes mowing, weeding, and debris removal on a weekly basis. Trimming, replanting, and replacement of mulch shall be performed on an as-needed basis to prevent exposure of erodible surfaces. Trimmings, clippings, and other landscape wastes shall be properly disposed of in accordance with local regulations. Materials temporarily stockpiled during maintenance activities shall be placed away from water courses and storm drain inlets. Frequency: Monthly Milan Capital Management, Inc. Yes N4. BMP Maintenance Maintenance of structural BMPs implemented at the project site shall be performed at the frequency prescribed in the O&M Plan included in this WQMP (Appendix D). Records of inspections and BMP maintenance shall be kept by the owner/developer and shall be available for review upon request. Frequency: Ongoing Milan Capital Management, Inc. City of Orange OPERATIONS AND MAINTENANCE PLAN Page 4 of 12 BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Applicable? Yes/No BMP Name and BMP Implementation, Maintenance and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility Yes N11. Common Area Litter Control Litter patrol, violations investigations, reporting and other litter control activities shall be performed on a weekly basis and in conjunction with routine maintenance activities. Frequency: Annually Milan Capital Management, Inc. Yes N12. Employee Training Educate all new employees/ managers on storm water pollution prevention, particularly good housekeeping practices, prior to the start of the rainy season (October 1). Refresher courses shall be conducted on an as needed basis. Frequency: Annually Milan Capital Management, Inc. Yes N14. Common Area Catch Basin Inspection Catch basin inlets and other drainage facilities shall be inspected after each storm event and once per year. Storm drain inlets and other drainage facilities shall be cleaned prior to the rainy season, by October 1 each year. City of Orange Yes N15. Street Sweeping Private Streets and Parking Lots Private streets and parking lots will be swept on a quarterly basis, at minimum. City of Orange STRUCTURAL SOURCE CONTROL BMPs OPERATIONS AND MAINTENANCE PLAN Page 5 of 12 BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Applicable? Yes/No BMP Name and BMP Implementation, Maintenance and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility Yes S1. Provide storm drain system stenciling and signage Storm drain stencils shall be inspected for legibility, at minimum, once prior to the storm season, no later than October 1 each year. Those determined to be illegible will be re-stenciled as soon as possible. Frequency: Annually City of Orange Yes S4. Use efficient irrigation systems & landscape design, water conservation, smart controllers, and source control In conjunction with routine maintenance activities, verify that landscape design continues to function properly by adjusting properly to eliminate overspray to hardscape areas, and to verify that irrigation timing and cycle lengths are adjusted in accordance with water demands, given time of year, weather, and day or night time temperatures. System testing shall occur twice per year. Water from testing/flushing shall be collected and properly disposed to the sewer system and shall not discharge to the storm drain system. Frequency: Weekly Visual inspection, testing 2x per year Milan Capital Management, Inc. OPERATIONS AND MAINTENANCE PLAN Page 6 of 12 BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Applicable? Yes/No BMP Name and BMP Implementation, Maintenance and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility Yes S5. Protect slopes and channels and provide energy dissipation To be performed in conjunction with maintenance activities. Maintain vegetative cover and/or mulch to eliminate exposed soils. Any eroded surfaces to be repaired immediately. Inspections to be performed twice each year (spring and fall) and after major storm events to check for signs of erosion, gullies, and sloughing. Frequency: Monthly Milan Capital Management, Inc. OPERATIONS AND MAINTENANCE PLAN Page 7 of 12 BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Name and BMP Implementation, Maintenance and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility LOW IMPACT DEVELOPMENT BMPs Infiltration BMP # 1: Bioretention without Underdrains Bioretention planters with underdrains are plant-based biotreatment systems that typically consist of a ponding area, mulch layer, planting soils and plants. As storm water passes down through the planting soil, pollutants are filtered, adsorbed, biodegraded and sequestered by the soil and plants. Inspect BMPs routinely with general maintenance activities, as well as semi-annually or after major storm events to check for maintenance needs and function. Routine maintenance activities include: Maintain vegetation and media to perpetuate a robust vegetative and microbial community (thin/trim vegetation, replace spent media and mulch). Periodically remove dead vegetative biomass to prevent export of nutrients or clogging of the system. Remove accumulated sediment before it significantly interferes with system function. Conduct maintenance to prevent surface clogging (surface scarring, raking, mulch replacement, etc.). Maintain splash blocks/energy dissipation and scour-protection as required based on facility inspection. Routinely remove accumulated sediment at the inlet and outlet and trash and debris from the area. Repair torn or broken liners as necessary. Major maintenance shall be provided when the performance of the facility declines significantly and cannot be restored through routine Milan Capital Management, Inc. OPERATIONS AND MAINTENANCE PLAN Page 8 of 12 BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Name and BMP Implementation, Maintenance and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility maintenance. Major maintenance activities include: Replace media / planting soils as triggered by reduction in filtration/infiltration rates or decline in health of biological processes. Provide major sediment removal to restore volumetric capacity of basin-type BMPs. Repair or modify inlets/outlets to restore original function or enhance function based on observations of performance. Frequency: 2x per year Biotreatment BMP #1: Modular Wetland Systems (MWS) Modular Wetlands by Modular Wetlands Systems, Inc. are proprietary biotreatment systems that utilize multi-stage treatment processes including screening media filtration, settling, and biofiltration. The pre-treatment chamber contains the first three stages of treatment and includes a catch basin inlet filter to capture trash, debris, gross solids and sediments, a settling chamber for separating out larger solids, and a media filter cartridge for capturing fine TSS, metals, nutrients, and bacteria. Runoff then flows through the wetland chamber where treatment is achieved through a variety of physical, chemical, and biological processes. As storm water passes down through the planting soil, pollutants are filtered, adsorbed, biodegraded and sequestered by the soil and plants, functioning similar to bioretention systems. The discharge chamber at the end of the unit collects treated flows and discharges back into the storm drain system. The Modular Wetland units shall be maintained in accordance with manufacturer’s specifications. The system shall be inspected at a minimum of once every six months, prior to the start of the rainy season (October 1) each year, and after major storm events. Typical maintenance includes: Removing trash & debris from the catch basin screening filter (by hand, 2x per year at a minimum). Removal of sediment and solids in the settlement chamber (vacuum truck, once per year at a minimum). Replacement of the BioMediaGREENTM filter cartridge and drain-down filter (if equipped, once per year at a minimum) Trim plants within the wetland chamber as City of Orange OPERATIONS AND MAINTENANCE PLAN Page 9 of 12 BMP INSPECTION & MAINTENANCE RESPONSIBILITY MATRIX BMP Name and BMP Implementation, Maintenance and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility needed in conjunction with routine landscape maintenance activities (typically 2x per year). No fertilizer shall be used. Wetland chamber should be inspected during rain events to verify flow through the system. If little to no flow is observed from the lower valve or orifice plate, the wetland media may require replacement. If prior treatment stages are properly maintained, the life of the wetland media can be up to 20 years. Frequency: 2x per year O PERATIONS AND M AINTENANCE P LAN Page 10 of 12 Required Permits Permits are not required for the implementation, operation, and maintenance of the BMPs. Forms to Record BMP Implementation, Maintenance, and Inspection The form that will be used to record implementation, maintenance, and inspection of BMPs is attached. Recordkeeping All records must be maintained for at least five (5) years and must be made available for review upon request. Waste Management Any waste generated from maintenance activities will be disposed of properly. Wash water and other waste from maintenance activities is not to be discharged or disposed of into the storm drain system. Clippings from landscape maintenance (i.e. prunings) will be collected and disposed of properly off- site, and will not be washed into the streets, local area drains/conveyances, or catch basin inlets. RECORD OF BMP IMPLEMENTATION, MAINTENANCE, AND INSPECTION Today’s Date: Name of Person Performing Activity (Printed): Signature: BMP Name (As Shown in O&M Plan) Brief Description of Implementation, Maintenance, and Inspection Activity Performed RECORD OF BMP IMPLEMENTATION, MAINTENANCE, AND INSPECTION Today’s Date: Name of Person Performing Activity (Printed): Signature: BMP Name (As Shown in O&M Plan) Brief Description of Implementation, Maintenance, and Inspection Activity Performed TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-28 December 20, 2013 INF-3: Bioretention with no Underdrain Bioretention stormwater treatment facilities are landscaped shallow depressions that capture and filter stormwater runoff. These facilities function as a soil and plant-based filtration device that removes pollutants through a variety of physical, biological, and chemical treatment processes. The facilities normally consist of a ponding area, mulch layer, planting soils, and plants. As stormwater passes down through the planting soil, pollutants are filtered, adsorbed, and biodegraded by the soil and plants. For areas with low permeability native soils or steep slopes, bioretention areas can be designed with an underdrain system that routes the treated runoff to the storm drain system rather than depending entirely on infiltration. Feasibility Screening Considerations x Bioretention with no underdrains shall pass infiltration infeasibility screening criteria to be considered for use. Opportunity Criteria x Land use may include commercial, residential, mixed use, institutional, and subdivisions. Bioretention may also be applied in parking lot islands, cul-de-sacs, traffic circles, road shoulders, and road medians. x Drainage area is ≤ 5 acres, preferrably ≤ 1 acre. x Area available for infiltration. x Soils are adequate for infiltration or can be amended to improve infiltration capacity. Site slope is less than 15 percent. OC-Specific Design Criteria and Considerations □ Placement of BMPs should observe geotechnical recommendations with respect to geological hazards (e.g. landslides, liquefaction zones, erosion, etc.) and set -backs (e.g., foundations, utilities, roadways, etc.) □ Depth to mounded seasonally high groundwater shall not be less than 5 feet. □ If sheet flow is conveyed to the treatment area over stabilized grassed areas, the site must be graded in such a way that minimizes erosive conditions; sheet flow velocities should not exceed 1 foot per second. □ Ponding depth should not exceed 18 inches; fencing may be required if ponding depth exceeds 6 inches to mitigate the risk of drowning. □ Planting/storage media shall be based on the recommendations contained in MISC-1: Planting/Storage Media □ The minimum amended soil depth is 1.5 feet (3 feet is preferred). □ The maximum drawdown time of the planting soil is 48 hours. Also known as: ¾Rain gardens ¾Infiltration planter Bioretention Source: Geosyntec Consultants TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-29 December 20, 2013 □ Infiltration pathways may need to be restricted due to the close proximity of roads, foundations, or other infrastructure. A geomembrane liner, or other equivalent water proofing, may be placed along the vertical walls to reduce lateral flows. This liner should have a minimum thickness of 30 mils. □ Plant materials should be tolerant of summer drought, ponding fluctuations, and saturated soil conditions for 48 hours; native plant species and/or hardy cultivars that are not invasive and do not require chemical fertilizers or pesticides should be used to the maximum extent feasible. □ The bioretention area should be covered with 2-4 inches (average 3 inches) of mulch at startup and an additional placement of 1-2 inches of mulch should be added annually. □ An optional gravel drainage layer may be installed below planting media to augment storage volume. □ An overflow device is required at the top of the ponding depth. □ Dispersed flow or energy dissipation (i.e. splash rocks) for piped inlets should be provided at basin inlet to prevent erosion. Simple Sizing Method for Bioretention with no Underdrain If the Simple Design Capture Volume Sizing Method described in Appendix III.3.1 is used to size a bioretention area with underdrains, the user calculates the DCV and designs the system with geometry required to draw down the DCV in 48 hours. The sizing steps are as follows: Step 1: Determine the Bioretention Design Capture Volume Calculate the DCV using the Simple Design Capture Volume Sizing Method described in Appendix III.3.1. Step 2: Determine the 48-hour Ponding Depth The depth of effective storage depth that can be drawn down in 48 hours can be calculated using the following equation: d48 = KDESIGN × 4 Where: d48 = bioretention 48-hour effective depth, ft KDESIGN = bioretention design infiltration rate, in/hr (See Appendix VII) This is the maximum effective depth of the basin below the overflow device to achieve drawdown in 48 hours. Effective depth includes ponding water and media/aggregate pore space. Step 3: Design System Geometry to Provide d48 Design system geometry such that d48 ≥ dEFFECTIVE = (dP + nMdM + nGdG) Where: d48 = depth of water that can drain in 48 hours dEFFECTIVE = total effective depth of water stored in bioretention area, ft dP = bioretention ponding depth, ft (should be less than or equal to 1.5 ft) nM = bioretention media porosity dM = bioretention media depth, ft TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-30 December 20, 2013 nG = bioretention gravel layer porosity; 0.35 may be assumed where other information is not available dG = bioretention gravel layer depth, ft Step 4: Calculate the Required Infiltrating Area The required infiltrating area (i.e. measured at the media surface) can be calculated using the following equation: A = DCV / dEFFECTIVE Where: A = required infiltrating area, sq-ft (measured as the media surface area) DCV = design capture volume, cu-ft (see Step 1) dEFFECTIVE = total effective depth of water stored in bioretention area, ft (from Step 3) This does not include the side slopes, access roads, etc. which would increase bioretention footprint. Capture Efficiency Method for Bioretention with no Underdrain If BMP geometry has already been defined and deviates from the 48 hour drawdown time, the designer can use the Capture Efficiency Method for Volume-Based, Constant Drawdown BMPs (See Appendix III.3.2) to determine the fraction of the DCV that must be provided to manage 80 percent of average annual runoff volume. This method accounts for drawdown time different than 48 hours. Step 1: Determine the drawdown time associated with the selected basin geometry DD = (dEFFECTIVE / KDESIGN) × 12 in/ft Where: DD = time to completely drain infiltration basin ponding depth, hours dEFFECTIVE ≤ (dP + nMdM + nGdG) dP = bioretention ponding depth, ft (should be less than or equal to 1.5 ft) nM = bioretention media porosity dM = bioretention media depth, ft nG = bioretention gravel layer porosity; 0.35 may be assumed where other information is not available dG = bioretention gravel layer depth, ft KDESIGN = basin design infiltration rate, in/hr (See Appendix VII) Step 2: Determine the Required Adjusted DCV for this Drawdown Time Use the Capture Efficiency Method for Volume-Based, Constant Drawdown BMPs (See Appendix III.3.2) to calculate the fraction of the DCV the basin must hold to achieve 80 percent capture of average annual stormwater runoff volume based on the basin drawdown time calculated above. Step 4: Check that the Bioretention Effective Depth Drains in no Greater than 96 Hours DD = (dEFFECTIVE / KDESIGN) × 12 Where: DD = time to completely drain bioretention facility, hours dEFFECTIVE = total effective depth of water stored in bioretention area, ft (from Step 3) KDESIGN = basin design infiltration rate, in/hr (See Appendix VII) TECHNICAL GUIDANCE DOCUMENT APPENDICES XIV-31 December 20, 2013 If DDALL is greater than 96 hours, adjust bioretention media depth and/or gravel layer depth until DD is less than 96 hours. This duration is based on preventing extended periods of saturation from causing plant mortality. Step 5: Determine the Basin Infiltrating Area Needed The required infiltrating area (i.e. the surface area of the top of the media layer) can be calculated using the following equation: A = DCV/ dEFFECTIVE Where: A = required infiltrating area, sq-ft (measured at the media surface) DCV = design capture volume, adjusted for drawdown time, cu-ft (see Step 1) dEFFECTIVE = total effective depth of water stored in bioretention area, ft (from Step 3) This does not include the side slopes, access roads, etc. which would increase bioretention footprint. If the area required is greater than the selected basin area, adjust surface area or adjust ponding depth and recalculate required area until the required area is achieved. Configuration for Use in a Treatment Train x Bioretention areas may be preceeded in a treatment train by HSCs in the drainage area, which would reduce the required volume of the bioretention cell. x Bioretention areas can be incorporated in a treatment train to provide enhanced water quality treatment and reductions in runoff volume and rate. For example, runoff can be collected from a roadway in a vegetated swale that then flows to a bioretention area. Similarly, bioretention could be used to manage overflow from a cistern. Additional References for Design Guidance x CASQA BMP Handbook for New and Redevelopment: http://www.cabmphandbooks.com/Documents/Development/TC-32.pdf x SMC LID Manual (pp 68): http://www.lowimpactdevelopment.org/guest75/pub/All_Projects/SoCal_LID_Manual/SoCalL ID_Manual_FINAL_040910.pdf x Los Angeles County Stormwater BMP Design and Maintenance Manual, Chapter 5: http://dpw.lacounty.gov/DES/design_manuals/StormwaterBMPDesignandMaintenance.pdf x San Diego County LID Handbook Appendix 4 (Factsheet 7): http://www.sdcounty.ca.gov/dplu/docs/LID-Appendices.pdf x Los Angeles Unified School District (LAUSD) Stormwater Technical Manual, Chapter 4. http://www.laschools.org/employee/design/fs-studies-and- reports/download/white_paper_report_material/Storm_Water_Technical_Manual_2009-opt- red.pdf?version_id=76975850 County of Los Angeles Low Impact Development Standards Manual, Chapter 5: http://dpw.lacounty.gov/wmd/LA_County_LID_Manual.pdf www.modularwetlands.com Inspection Guidelines for Modular Wetland System - Linear Inspection Summary o Inspect Pre-Treatment, Biofiltration and Discharge Chambers – average inspection interval is 6 to 12 months. (15 minute average inspection time). o NOTE: Pollutant loading varies greatly from site to site and no two sites are the same. Therefore, the first year requires inspection monthly during the wet season and every other month during the dry season in order to observe and record the amount of pollutant loading the system is receiving. System Diagram Access to separation chamber and pre-filter cartridges 1 Pre-treatment Chamber 2 Biofiltration Chamber 3 Discharge Chamber Access to discharge chamber and orifice control www.modularwetlands.com Inspection Overview As with all stormwater BMPs inspection and maintenance on the MWS Linear is necessary. Stormwater regulations require that all BMPs be inspected and maintained to ensure they are operating as designed to allow for effective pollutant removal and provide protection to receiving water bodies. It is recommended that inspections be performed multiple times during the first year to assess the site specific loading conditions. This is recommended because pollutant loading and pollutant characteristics can vary greatly from site to site. Variables such as nearby soil erosion or construction sites, winter sanding on roads, amount of daily traffic and land use can increase pollutant loading on the system. The first year of inspections can be used to set inspection and maintenance intervals for subsequent years to ensure appropriate maintenance is provided. Without appropriate maintenance a BMP will exceed its storage capacity which can negatively affect its continued performance in removing and retaining captured pollutants. Inspection Equipment Following is a list of equipment to allow for simple and effective inspection of the MWS Linear: Modular Wetland Inspection Form Flashlight Manhole hook or appropriate tools to remove access hatches and covers Appropriate traffic control signage and procedures Measuring pole and/or tape measure. Protective clothing and eye protection. 7/16” open or closed ended wrench. Large permanent black marker (initial inspections only – first year) Note: entering a confined space requires appropriate safety and certification. It is generally not required for routine inspections of the system. www.modularwetlands.com Inspection Steps The core to any successful stormwater BMP maintenance program is routine inspections. The inspection steps required on the MWS Linear are quick and easy. As mentioned above the first year should be seen as the maintenance interval establishment phase. During the first year more frequent inspections should occur in order to gather loading data and maintenance requirements for that specific site. This information can be used to establish a base for long term inspection and maintenance interval requirements. The MWS Linear can be inspected though visual observation without entry into the system. All necessary pre-inspection steps must be carried out before inspection occurs, especially traffic control and other safety measures to protect the inspector and near-by pedestrians from any dangers associated with an open access hatch or manhole. Once these access covers have been safely opened the inspection process can proceed: Prepare the inspection form by writing in the necessary information including project name, location, date & time, unit number and other info (see inspection form). Observe the inside of the system through the access hatches. If minimal light is available and vision into the unit is impaired utilize a flashlight to see inside the system and all of its chambers. Look for any out of the ordinary obstructions in the inflow pipe, pre-treatment chamber, biofiltration chamber, discharge chamber or outflow pipe. Write down any observations on the inspection form. Through observation and/or digital photographs estimate the amount of trash, debris and sediment accumulated in the pre-treatment chamber. Utilizing a tape measure or measuring stick estimate the amount of trash, debris and sediment in this chamber. Record this depth on the inspection form. www.modularwetlands.com Through visual observation inspect the condition of the pre-filter cartridges. Look for excessive build-up of sediments on the cartridges, any build-up on the top of the cartridges, or clogging of the holes. Record this information on the inspection form. The pre-filter cartridges can further be inspected by removing the cartridge tops and assessing the color of the BioMediaGREEN filter cubes (requires entry into pre-treatment chamber – see notes above regarding confined space entry). Record the color of the material. New material is a light green in color. As the media becomes clogged it will turn darker in color, eventually becoming dark brown or black. Using the below color indicator record the percentage of media exhausted. The biofiltration chamber is generally maintenance free due to the system’s advanced pre- treatment chamber. For units which have open planters with vegetation it is recommended that the vegetation be inspected. Look for any plants that are dead or showing signs of disease or other negative stressors. Record the general health of the plants on the inspection and indicate through visual observation or digital photographs if trimming of the vegetation is needed. The discharge chamber houses the orifice control structure and is connected to the outflow pipe. It is important to check to ensure the orifice is in proper operating conditions and free of any obstructions. Generally, the discharge chamber will be clean and free of debris. Inspect the water marks on the side walls. If possible, inspect the discharge chamber during a rain event to assess the amount of flow leaving the system while it is at 100% capacity (pre- treatment chamber water level at peak HGL). The water level of the flowing water should be compared to the watermark level on the side walls which is an indicator of the highest discharge rate the system achieved when initially installed. Record on the form is there is any difference in level from watermark in inches. 0% -- Percent Clogged -- 100% New BioMediaGREEN Exhausted BioMediaGREEN 85% www.modularwetlands.com NOTE: During the first few storms the water level in the outflow chamber should be observed and a 6” long horizontal watermark line drawn (using a large permanent marker) at the water level in the discharge chamber while the system is operating at 100% capacity. The diagram below illustrates where a line should be drawn. This line is a reference point for future inspections of the system: Water level in the discharge chamber is a function of flow rate and pipe size. Observation of water level during the first few months of operation can be used as a benchmark level for future inspections. The initial mark and all future observations shall be made when system is at 100% capacity (water level at maximum level in pre-treatment chamber). If future water levels are below this mark when system is at 100% capacity this is an indicator that maintenance to the pre-filter cartridges may be needed. Finalize inspection report for analysis by the maintenance manager to determine if maintenance is required. Water Level Mark Water Level Marks Using a permanent marker draw a 6 inch long horizontal line, as shown, at the higher water level in the MWS Linear discharge chamber. www.modularwetlands.com Maintenance Indicators Based upon observations made during inspection, maintenance of the system may be required based on the following indicators: Missing or damaged internal components or cartridges. Obstructions in the system or its inlet or outlet. Excessive accumulation of floatables in the pre-treatment chamber in which the length and width of the chamber is fully impacted more than 18”. Excessive accumulation of sediment in the pre-treatment chamber of more than 6” in depth. www.modularwetlands.com Excessive accumulation of sediment on the BioMediaGREEN media housed within the pre- filter cartridges. The following chart shows photos of the condition of the BioMediaGREEN contained within the pre-filter cartridges. When media is more than 85% clogged replacement is required. Overgrown vegetation. Water level in discharge chamber during 100% operating capacity (pre-treatment chamber water level at max height) is lower than the watermark by 20%. 0% -- Percent Clogged -- 100% New BioMediaGREEN Exhausted BioMediaGREEN 85% www.modularwetlands.com Inspection Notes 1. Following maintenance and/or inspection, it is recommended the maintenance operator prepare a maintenance/inspection record. The record should include any maintenance activities performed, amount and description of debris collected, and condition of the system and its various filter mechanisms. 2. The owner should keep maintenance/inspection record(s) for a minimum of five years from the date of maintenance. These records should be made available to the governing municipality for inspection upon request at any time. 3. Transport all debris, trash, organics and sediments to approved facility for disposal in accordance with local and state requirements. 4. Entry into chambers may require confined space training based on state and local regulations. 5. No fertilizer shall be used in the Biofiltration Chamber. 6. Irrigation should be provided as recommended by manufacturer and/or landscape architect. Amount of irrigation required is dependent on plant species. Some plants may not require irrigation after initial establishment. www.modularwetlands.com Maintenance Guidelines for Modular Wetland System - Linear Maintenance Summary o Remove Sediment from Pre-Treatment Chamber – average maintenance interval is 12 to 24 months. (10 minute average service time). o Replace Pre-Filter Cartridge Media – average maintenance interval 12 to 24 months. (10-15 minute per cartridge average service time). o Trim Vegetation – average maintenance interval is 6 to 12 months. (Service time varies). System Diagram Access to separation chamber and pre-filter cartridge 1 Pre-treatment Chamber 2 Biofiltration Chamber 3 Discharge Chamber www.modularwetlands.com Maintenance Overview The time has come to maintain your Modular Wetland System Linear (MWS Linear). To ensure successful and efficient maintenance on the system we recommend the following. The MWS Linear can be maintained by removing the access hatches over the systems various chambers. All necessary pre-maintenance steps must be carried out before maintenance occurs, especially traffic control and other safety measures to protect the inspector and near-by pedestrians from any dangers associated with an open access hatch or manhole. Once traffic control has been set up per local and state regulations and access covers have been safely opened the maintenance process can begin. It should be noted that some maintenance activities require confined space entry. All confined space requirements must be strictly followed before entry into the system. In addition the following is recommended: Prepare the maintenance form by writing in the necessary information including project name, location, date & time, unit number and other info (see maintenance form). Set up all appropriate safety and cleaning equipment. Ensure traffic control is set up and properly positioned. Prepare a pre-checks (OSHA, safety, confined space entry) are performed. Maintenance Equipment Following is a list of equipment required for maintenance of the MWS Linear: Modular Wetland Maintenance Form Manhole hook or appropriate tools to access hatches and covers Protective clothing, flashlight and eye protection. 7/16” open or closed ended wrench. Vacuum assisted truck with pressure washer. Replacement BioMediaGREEN for Pre-Filter Cartridges if required (order from manufacturer). www.modularwetlands.com Maintenance Steps 1. Pre-treatment Chamber (bottom of chamber) A. Remove access hatch or manhole cover over pre-treatment chamber and position vacuum truck accordingly. B. With a pressure washer spray down pollutants accumulated on walls and pre-filter cartridges. C. Vacuum out Pre-Treatment Chamber and remove all accumulated pollutants including trash, debris and sediments. Be sure to vacuum the floor until pervious pavers are visible and clean. D. If Pre-Filter Cartridges require media replacement move onto step 2. If not, replace access hatch or manhole cover. Removal of access hatch to gain access below. Insertion of vacuum hose into separation chamber. Removal of trash, sediment and debris. Fully cleaned separation chamber. www.modularwetlands.com 2. Pre-Filter Cartridges (attached to wall of pre-treatment chamber) A. After finishing step 1 enter pre-treatment chamber. B. Unscrew the two bolts holding the lid on each cartridge filter and remove lid. C. Place the vacuum hose over each individual media filter to suck out filter media. D. Once filter media has been sucked use a pressure washer to spray down inside of the cartridge and it’s containing media cages. Remove cleaned media cages and place to the side. Once removed the vacuum hose can be inserted into the cartridge to vacuum out any remaining material near the bottom of the cartridge. Pre-filter cartridges with tops on. Inside cartridges showing media filters ready for replacement. Vacuuming out of media filters. www.modularwetlands.com E. Reinstall media cages and fill with new media from manufacturer or outside supplier. Manufacturer will provide specification of media and sources to purchase. Utilize the manufacture provided refilling trey and place on top of cartridge. Fill trey with new bulk media and shake down into place. Using your hands slightly compact media into each filter cage. Once cages are full removed refilling trey and replace cartridge top ensuring bolts are properly tightened. F. Exit pre-treatment chamber. Replace access hatch or manhole cover. 3. Biofiltration Chamber (middle vegetated chamber) A. In general, the biofiltration chamber is maintenance free with the exception of maintaining the vegetation. Using standard gardening tools properly trim back the vegetation to healthy levels. The MWS Linear utilizes vegetation similar to surrounding landscape areas therefore trim vegetation to match surrounding vegetation. If any plants have died replace plants with new ones: Refilling trey for media replacement. Refilling trey on cartridge with bulk media. www.modularwetlands.com Inspection Notes 1. Following maintenance and/or inspection, it is recommended the maintenance operator prepare a maintenance/inspection record. The record should include any maintenance activities performed, amount and description of debris collected, and condition of the system and its various filter mechanisms. 2. The owner should keep maintenance/inspection record(s) for a minimum of five years from the date of maintenance. These records should be made available to the governing municipality for inspection upon request at any time. 3. Transport all debris, trash, organics and sediments to approved facility for disposal in accordance with local and state requirements. 4. Entry into chambers may require confined space training based on state and local regulations. 5. No fertilizer shall be used in the Biofiltration Chamber. 6. Irrigation should be provided as recommended by manufacturer and/or landscape architect. Amount of irrigation required is dependent on plant species. Some plants may not require irrigation after initial establishment. www.modularwetlands.com Inspection Form Modular Wetland System, Inc. P. 760.433-7640 F. 760-433-3176 E. Info@modularwetlands.com For Office Use Only (city) (Zip Code)(Reviewed By) Owner / Management Company (Date) Contact Phone ( )_ Inspector Name Date / / Time AM / PM Weather Condition Additional Notes Yes Depth: Yes No Modular Wetland System Type (Curb, Grate or UG Vault):Size (22', 14' or etc.): Other Inspection Items: Storm Event in Last 72-hours? No Yes Type of Inspection Routine Follow Up Complaint Storm Office personnel to complete section to the left. 2972 San Luis Rey Road, Oceanside, CA 92058 P (760) 433-7640 F (760) 433-3176 Inspection Report Modular Wetlands System Is the filter insert (if applicable) at capacity and/or is there an accumulation of debris/trash on the shelf system? Does the cartridge filter media need replacement in pre-treatment chamber and/or discharge chamber? Any signs of improper functioning in the discharge chamber? Note issues in comments section. Chamber: Is the inlet/outlet pipe or drain down pipe damaged or otherwise not functioning properly? Structural Integrity: Working Condition: Is there evidence of illicit discharge or excessive oil, grease, or other automobile fluids entering and clogging the unit? Is there standing water in inappropriate areas after a dry period? Damage to pre-treatment access cover (manhole cover/grate) or cannot be opened using normal lifting pressure? Damage to discharge chamber access cover (manhole cover/grate) or cannot be opened using normal lifting pressure? Does the MWS unit show signs of structural deterioration (cracks in the wall, damage to frame)? Project Name Project Address Inspection Checklist CommentsNo Does the depth of sediment/trash/debris suggest a blockage of the inflow pipe, bypass or cartridge filter? If yes, specify which one in the comments section. Note depth of accumulation in in pre-treatment chamber. Is there a septic or foul odor coming from inside the system? Is there an accumulation of sediment/trash/debris in the wetland media (if applicable)? Is it evident that the plants are alive and healthy (if applicable)? Please note Plant Information below. Sediment / Silt / Clay Trash / Bags / Bottles Green Waste / Leaves / Foliage Waste:Plant Information No Cleaning Needed Recommended Maintenance Additional Notes: Damage to Plants Plant Replacement Plant Trimming Schedule Maintenance as Planned Needs Immediate Maintenance www.modularwetlands.com Maintenance Report Modular Wetland System, Inc. P. 760.433-7640 F. 760-433-3176 E. Info@modularwetlands.com For Office Use Only (city) (Zip Code)(Reviewed By) Owner / Management Company (Date) Contact Phone ( )_ Inspector Name Date / / Time AM / PM Weather Condition Additional Notes Site Map # Comments: 2972 San Luis Rey Road, Oceanside, CA 92058 P. 760.433.7640 F. 760.433.3176 Inlet and Outlet Pipe Condition Drain Down Pipe Condition Discharge Chamber Condition Drain Down Media Condition Plant Condition Media Filter Condition Long: MWS Sedimentation Basin Total Debris Accumulation Condition of Media 25/50/75/100 (will be changed @ 75%) Operational Per Manufactures' Specifications (If not, why?) Lat:MWS Catch Basins GPS Coordinates of Insert Manufacturer / Description / Sizing Trash Accumulation Foliage Accumulation Sediment Accumulation Type of Inspection Routine Follow Up Complaint Storm Storm Event in Last 72-hours? No Yes Office personnel to complete section to the left. Project Address Project Name Cleaning and Maintenance Report Modular Wetlands System APPENDIX E GEOTECHNICAL INFILTRATION TESTING 1 172-02 3/1/15 Ginter & Associates, Inc. 27631 Durazno27631 Durazno27631 Durazno27631 Durazno Mission Viejo, CA 92692Mission Viejo, CA 92692Mission Viejo, CA 92692Mission Viejo, CA 92692 ofc (949) 581ofc (949) 581ofc (949) 581ofc (949) 581----2363 cell (714) 4782363 cell (714) 4782363 cell (714) 4782363 cell (714) 478----1167116711671167 JMI Properties/Santiago Partners, LLC March 1, 2015 c/o Milan Capital Mgmt., Inc. 888 South Disneyland Drive, Suite 101 Project # 172-02 Anaheim, CA 92802 Attn: Mr. Bret B. Bernard INFILTRATION STUDY USING DOUBLE-RING INFILTROMETER Proposed On-Site Storm Water Disposal System Mara Brandman Arena Property Santiago Canyon Road, City of Orange, California Reference: Model WQMP Technical Guidance Document Appendix VII-Infiltration Rate Evaluation Protocol and Factor of Safety Recommendations; Appendix VIII-Groundwater-related Infiltration Feasibility Criteria Dear Mr. Bernard: Pursuant to your request and authorization, we performed five field infiltration tests at different locations (IP-1 through IP-5) using double-ring infiltrometer. The approximate locations of the field infiltration tests are shown in the attached Figure -1. The tests were performed at approximately 5 feet below existing grades. The tests were performed by driving two circular rings (a smaller inner ring and a larger outer ring) into the ground several inches, filling both the outer and inner rings with water several times and measuring the water level in the inner ring versus time. The readings continued until a relatively constant rate of drop was observed. Infiltration rates for the five tests are presented below: Test Location Test Date Depth Below Existing Grade Infiltration Rate IP-1 2/10/2015 5 feet 0.5 in / hr IP-2 2/10/2015 5 feet 4.0 in / hr IP-3 2/10/2015 5 feet 4.0 in / hr IP-4 2/11/2015 5 feet 3.0 in / hr 2 172-02 3/1/15 IP-5 2/11/2015 5 feet 0.5 in / hr We greatly appreciate the opportunity to provide our services and look forward to working with you and the other project consultants. If you have any questions or require additional information, please contact the undersigned. Respectfully submitted, Dave Ginter R.G., C.E.G. Vela “Ganesh” Ganeshwara P.E., G.E. Principal Engineering Geologist/President Consulting Geotechnical Engineer Attachments: Photo – Infiltration Device Figure I - Infiltration Test Location Map APPENDIX F HYDROLOGY INFORMATION (Q2 – TWO-YEAR FREQUENCY STORM EVALUATION) P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 1 of 8 ____________________________________________________________________________ **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE (Reference: 1986 ORANGE COUNTY HYDROLOGY CRITERION) (c) Copyright 1983-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1355 Analysis prepared by: Fuscoe Engineering 16795 Von Karman Suite 210 Irvine CA 92606 ************************** DESCRIPTION OF STUDY ************************** * MB Arena Site. TTM 17847. * * Existing Condition Hydrology Calculation. * * 2 Year Frequency. * ************************************************************************** FILE NAME: _E04.DAT TIME/DATE OF STUDY: 10:30 07/17/2018 ============================================================================ USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: ============================================================================ --*TIME-OF-CONCENTRATION MODEL*-- USER SPECIFIED STORM EVENT(YEAR) = 2.00 SPECIFIED MINIMUM PIPE SIZE(INCH) = 18.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.80 *DATA BANK RAINFALL USED* *ANTECEDENT MOISTURE CONDITION (AMC) I ASSUMED FOR RATIONAL METHOD* *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) === ===== ========= ================= ====== ===== ====== ===== ======= 1 30.0 20.0 0.018/0.018/0.020 0.67 2.00 0.0313 0.167 0.0150 GLOBAL STREET FLOW-DEPTH CONSTRAINTS: 1. Relative Flow-Depth = 0.00 FEET as (Maximum Allowable Street Flow Depth) - (Top-of-Curb) 2. (Depth)*(Velocity) Constraint = 3.0 (FT*FT/S) *SIZE PIPE WITH A FLOW CAPACITY GREATER THAN OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.* *USER-SPECIFIED MINIMUM TOPOGRAPHIC SLOPE ADJUSTMENT NOT SELECTED **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 101.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< >>USE TIME-OF-CONCENTRATION NOMOGRAPH FOR INITIAL SUBAREA<< ============================================================================ INITIAL SUBAREA FLOW-LENGTH(FEET) = 273.00 ELEVATION DATA: UPSTREAM(FEET) = 426.00 DOWNSTREAM(FEET) = 405.00 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 2 of 8 Tc = K*[(LENGTH** 3.00)/(ELEVATION CHANGE)]**0.20 SUBAREA ANALYSIS USED MINIMUM Tc(MIN.) = 11.119 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.431 SUBAREA Tc AND LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS Tc LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN (MIN.) URBAN GOOD COVER "TURF" B 0.36 0.30 1.000 38 11.12 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 SUBAREA RUNOFF(CFS) = 0.37 TOTAL AREA(ACRES) = 0.36 PEAK FLOW RATE(CFS) = 0.37 **************************************************************************** FLOW PROCESS FROM NODE 101.00 TO NODE 102.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 405.00 DOWNSTREAM NODE ELEVATION(FEET) = 403.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 229.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.282 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 0.60 0.30 1.000 38 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.63 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 1.63 AVERAGE FLOW DEPTH(FEET) = 0.09 FLOOD WIDTH(FEET) = 8.21 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 2.35 Tc(MIN.) = 13.47 SUBAREA AREA(ACRES) = 0.60 SUBAREA RUNOFF(CFS) = 0.53 EFFECTIVE AREA(ACRES) = 0.96 AREA-AVERAGED Fm(INCH/HR) = 0.30 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 1.00 TOTAL AREA(ACRES) = 1.0 PEAK FLOW RATE(CFS) = 0.85 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.10 FLOOD WIDTH(FEET) = 9.31 FLOW VELOCITY(FEET/SEC.) = 1.75 DEPTH*VELOCITY(FT*FT/SEC) = 0.18 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 102.00 = 502.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 102.00 TO NODE 103.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 403.00 DOWNSTREAM NODE ELEVATION(FEET) = 401.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 141.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 3 of 8 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.228 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 0.67 0.30 1.000 38 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 1.13 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 2.25 AVERAGE FLOW DEPTH(FEET) = 0.10 FLOOD WIDTH(FEET) = 9.50 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 1.04 Tc(MIN.) = 14.51 SUBAREA AREA(ACRES) = 0.67 SUBAREA RUNOFF(CFS) = 0.56 EFFECTIVE AREA(ACRES) = 1.63 AREA-AVERAGED Fm(INCH/HR) = 0.30 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 1.00 TOTAL AREA(ACRES) = 1.6 PEAK FLOW RATE(CFS) = 1.36 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.11 FLOOD WIDTH(FEET) = 10.42 FLOW VELOCITY(FEET/SEC.) = 2.30 DEPTH*VELOCITY(FT*FT/SEC) = 0.26 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 103.00 = 643.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 103.00 TO NODE 103.00 IS CODE = 10 ---------------------------------------------------------------------------- >>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 <<<<< ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 103.00 TO NODE 103.00 IS CODE = 13 ---------------------------------------------------------------------------- >>>>>CLEAR THE MAIN-STREAM MEMORY<<<<< ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 200.00 TO NODE 201.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< >>USE TIME-OF-CONCENTRATION NOMOGRAPH FOR INITIAL SUBAREA<< ============================================================================ INITIAL SUBAREA FLOW-LENGTH(FEET) = 266.00 ELEVATION DATA: UPSTREAM(FEET) = 454.60 DOWNSTREAM(FEET) = 445.00 Tc = K*[(LENGTH** 3.00)/(ELEVATION CHANGE)]**0.20 SUBAREA ANALYSIS USED MINIMUM Tc(MIN.) = 5.512 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 2.140 SUBAREA Tc AND LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS Tc LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN (MIN.) COMMERCIAL B 0.24 0.30 0.100 36 5.51 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.100 SUBAREA RUNOFF(CFS) = 0.46 TOTAL AREA(ACRES) = 0.24 PEAK FLOW RATE(CFS) = 0.46 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 4 of 8 **************************************************************************** FLOW PROCESS FROM NODE 201.00 TO NODE 202.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 445.00 DOWNSTREAM NODE ELEVATION(FEET) = 435.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 162.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.973 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 0.20 0.30 1.000 38 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.61 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 3.21 AVERAGE FLOW DEPTH(FEET) = 0.06 FLOOD WIDTH(FEET) = 5.28 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 0.84 Tc(MIN.) = 6.35 SUBAREA AREA(ACRES) = 0.20 SUBAREA RUNOFF(CFS) = 0.30 EFFECTIVE AREA(ACRES) = 0.44 AREA-AVERAGED Fm(INCH/HR) = 0.15 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.51 TOTAL AREA(ACRES) = 0.4 PEAK FLOW RATE(CFS) = 0.72 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.07 FLOOD WIDTH(FEET) = 5.64 FLOW VELOCITY(FEET/SEC.) = 3.45 DEPTH*VELOCITY(FT*FT/SEC) = 0.23 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 202.00 = 428.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 202.00 TO NODE 203.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 435.00 DOWNSTREAM NODE ELEVATION(FEET) = 410.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 150.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.888 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 0.14 0.30 1.000 38 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.82 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 4.98 AVERAGE FLOW DEPTH(FEET) = 0.06 FLOOD WIDTH(FEET) = 5.00 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 5 of 8 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 0.50 Tc(MIN.) = 6.86 SUBAREA AREA(ACRES) = 0.14 SUBAREA RUNOFF(CFS) = 0.20 EFFECTIVE AREA(ACRES) = 0.58 AREA-AVERAGED Fm(INCH/HR) = 0.19 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.63 TOTAL AREA(ACRES) = 0.6 PEAK FLOW RATE(CFS) = 0.89 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.06 FLOOD WIDTH(FEET) = 5.09 FLOW VELOCITY(FEET/SEC.) = 4.94 DEPTH*VELOCITY(FT*FT/SEC) = 0.30 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 203.00 = 578.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 203.00 TO NODE 204.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 410.00 DOWNSTREAM NODE ELEVATION(FEET) = 405.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 252.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.685 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 1.16 0.30 1.000 38 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 1.60 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 2.79 AVERAGE FLOW DEPTH(FEET) = 0.11 FLOOD WIDTH(FEET) = 10.23 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 1.51 Tc(MIN.) = 8.36 SUBAREA AREA(ACRES) = 1.16 SUBAREA RUNOFF(CFS) = 1.45 EFFECTIVE AREA(ACRES) = 1.74 AREA-AVERAGED Fm(INCH/HR) = 0.26 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.88 TOTAL AREA(ACRES) = 1.7 PEAK FLOW RATE(CFS) = 2.23 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.13 FLOOD WIDTH(FEET) = 11.88 FLOW VELOCITY(FEET/SEC.) = 2.95 DEPTH*VELOCITY(FT*FT/SEC) = 0.38 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 204.00 = 830.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 204.00 TO NODE 205.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 405.00 DOWNSTREAM NODE ELEVATION(FEET) = 401.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 214.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 6 of 8 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.565 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 1.07 0.30 1.000 38 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 2.84 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 3.09 AVERAGE FLOW DEPTH(FEET) = 0.14 FLOOD WIDTH(FEET) = 13.17 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 1.15 Tc(MIN.) = 9.52 SUBAREA AREA(ACRES) = 1.07 SUBAREA RUNOFF(CFS) = 1.22 EFFECTIVE AREA(ACRES) = 2.81 AREA-AVERAGED Fm(INCH/HR) = 0.28 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.92 TOTAL AREA(ACRES) = 2.8 PEAK FLOW RATE(CFS) = 3.26 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.15 FLOOD WIDTH(FEET) = 14.09 FLOW VELOCITY(FEET/SEC.) = 3.12 DEPTH*VELOCITY(FT*FT/SEC) = 0.47 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 205.00 = 1044.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 205.00 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY<<<<< ============================================================================ ** MAIN STREAM CONFLUENCE DATA ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 3.26 9.52 1.565 0.30( 0.28) 0.92 2.8 200.00 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 205.00 = 1044.00 FEET. ** MEMORY BANK # 1 CONFLUENCE DATA ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 1.36 14.51 1.228 0.30( 0.30) 1.00 1.6 100.00 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 205.00 = 643.00 FEET. ** PEAK FLOW RATE TABLE ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 4.47 9.52 1.565 0.30( 0.28) 0.94 3.9 200.00 2 3.77 14.51 1.228 0.30( 0.29) 0.95 4.4 100.00 TOTAL AREA(ACRES) = 4.4 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 4.47 Tc(MIN.) = 9.517 EFFECTIVE AREA(ACRES) = 3.88 AREA-AVERAGED Fm(INCH/HR) = 0.28 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.94 TOTAL AREA(ACRES) = 4.4 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 205.00 = 1044.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 205.00 IS CODE = 12 ---------------------------------------------------------------------------- P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 7 of 8 >>>>>CLEAR MEMORY BANK # 1 <<<<< ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 206.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 401.00 DOWNSTREAM NODE ELEVATION(FEET) = 399.50 CHANNEL LENGTH THRU SUBAREA(FEET) = 401.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.05000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.341 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 1.22 0.30 1.000 38 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 1.000 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 5.04 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 2.28 AVERAGE FLOW DEPTH(FEET) = 0.28 FLOOD WIDTH(FEET) = 13.70 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 2.93 Tc(MIN.) = 12.44 SUBAREA AREA(ACRES) = 1.22 SUBAREA RUNOFF(CFS) = 1.14 EFFECTIVE AREA(ACRES) = 5.10 AREA-AVERAGED Fm(INCH/HR) = 0.29 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.96 TOTAL AREA(ACRES) = 5.7 PEAK FLOW RATE(CFS) = 4.84 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.27 FLOOD WIDTH(FEET) = 13.56 FLOW VELOCITY(FEET/SEC.) = 2.24 DEPTH*VELOCITY(FT*FT/SEC) = 0.61 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 206.00 = 1445.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 206.00 TO NODE 207.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 399.50 DOWNSTREAM NODE ELEVATION(FEET) = 398.80 CHANNEL LENGTH THRU SUBAREA(FEET) = 430.00 "V" GUTTER WIDTH(FEET) = 5.00 GUTTER HIKE(FEET) = 0.050 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.102 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN URBAN GOOD COVER "TURF" B 2.23 0.30 1.000 38 COMMERCIAL B 0.69 0.30 0.100 36 COMMERCIAL B 0.65 0.30 0.100 36 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_e04.docx 8 of 8 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.662 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 6.28 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 1.41 AVERAGE FLOW DEPTH(FEET) = 0.31 FLOOD WIDTH(FEET) = 29.69 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 5.09 Tc(MIN.) = 17.53 SUBAREA AREA(ACRES) = 3.57 SUBAREA RUNOFF(CFS) = 2.90 EFFECTIVE AREA(ACRES) = 8.67 AREA-AVERAGED Fm(INCH/HR) = 0.25 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.84 TOTAL AREA(ACRES) = 9.2 PEAK FLOW RATE(CFS) = 6.64 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.31 FLOOD WIDTH(FEET) = 30.43 FLOW VELOCITY(FEET/SEC.) = 1.42 DEPTH*VELOCITY(FT*FT/SEC) = 0.45 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 207.00 = 1875.00 FEET. ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 9.2 TC(MIN.) = 17.53 EFFECTIVE AREA(ACRES) = 8.67 AREA-AVERAGED Fm(INCH/HR)= 0.25 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.836 PEAK FLOW RATE(CFS) = 6.64 ** PEAK FLOW RATE TABLE ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 6.64 17.53 1.102 0.30( 0.25) 0.84 8.7 200.00 2 5.75 22.88 0.946 0.30( 0.25) 0.85 9.2 100.00 ============================================================================ ============================================================================ END OF RATIONAL METHOD ANALYSIS P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Small Area UH\_ex01.docx 1 of 3 ____________________________________________________________________________ **************************************************************************** SMALL AREA UNIT HYDROGRAPH MODEL ============================================================================ (C) Copyright 1989-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1355 Analysis prepared by: Fuscoe Engineering 16795 Von Karman Suite 210 Irvine CA 92606 **************************************************************************** ---------------------------------------------------------------------------- Problem Descriptions: MB Arena Site. TTM 17847. Existing Condition Runoff Volume Calculation. 2 Year Frequency. ---------------------------------------------------------------------------- RATIONAL METHOD CALIBRATION COEFFICIENT = 0.85 TOTAL CATCHMENT AREA(ACRES) = 9.23 SOIL-LOSS RATE, Fm,(INCH/HR) = 0.250 LOW LOSS FRACTION = 0.620 TIME OF CONCENTRATION(MIN.) = 17.53 SMALL AREA PEAK Q COMPUTED USING PEAK FLOW RATE FORMULA ORANGE COUNTY "VALLEY" RAINFALL VALUES ARE USED RETURN FREQUENCY(YEARS) = 2 5-MINUTE POINT RAINFALL VALUE(INCHES) = 0.19 30-MINUTE POINT RAINFALL VALUE(INCHES) = 0.40 1-HOUR POINT RAINFALL VALUE(INCHES) = 0.53 3-HOUR POINT RAINFALL VALUE(INCHES) = 0.89 6-HOUR POINT RAINFALL VALUE(INCHES) = 1.22 24-HOUR POINT RAINFALL VALUE(INCHES) = 2.05 ---------------------------------------------------------------------------- TOTAL CATCHMENT RUNOFF VOLUME(ACRE-FEET) = 0.59 TOTAL CATCHMENT SOIL-LOSS VOLUME(ACRE-FEET) = 0.99 **************************************************************************** TIME VOLUME Q 0. 2.5 5.0 7.5 10.0 (HOURS) (AF) (CFS) ---------------------------------------------------------------------------- 0.22 0.0012 0.10 Q . . . . 0.52 0.0035 0.10 Q . . . . 0.81 0.0058 0.10 Q . . . . 1.10 0.0082 0.10 Q . . . . 1.39 0.0106 0.10 Q . . . . 1.68 0.0130 0.10 Q . . . . 1.98 0.0155 0.10 Q . . . . 2.27 0.0180 0.10 Q . . . . 2.56 0.0205 0.11 Q . . . . 2.85 0.0231 0.11 Q . . . . 3.14 0.0256 0.11 Q . . . . 3.44 0.0283 0.11 Q . . . . 3.73 0.0309 0.11 Q . . . . 4.02 0.0337 0.11 Q . . . . 4.31 0.0364 0.11 Q . . . . P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Small Area UH\_ex01.docx 2 of 3 4.61 0.0392 0.12 Q . . . . 4.90 0.0420 0.12 Q . . . . 5.19 0.0449 0.12 Q . . . . 5.48 0.0478 0.12 Q . . . . 5.77 0.0508 0.12 Q . . . . 6.07 0.0539 0.13 Q . . . . 6.36 0.0569 0.13 Q . . . . 6.65 0.0601 0.13 Q . . . . 6.94 0.0633 0.13 Q . . . . 7.23 0.0666 0.14 Q . . . . 7.53 0.0699 0.14 Q . . . . 7.82 0.0733 0.14 Q . . . . 8.11 0.0768 0.15 Q . . . . 8.40 0.0803 0.15 Q . . . . 8.70 0.0840 0.15 Q . . . . 8.99 0.0877 0.16 Q . . . . 9.28 0.0915 0.16 Q . . . . 9.57 0.0955 0.16 Q . . . . 9.86 0.0995 0.17 Q . . . . 10.16 0.1037 0.17 Q . . . . 10.45 0.1080 0.18 Q . . . . 10.74 0.1124 0.19 Q . . . . 11.03 0.1170 0.19 Q . . . . 11.33 0.1217 0.20 Q . . . . 11.62 0.1266 0.21 Q . . . . 11.91 0.1317 0.21 Q . . . . 12.20 0.1374 0.25 .Q . . . . 12.49 0.1439 0.28 .Q . . . . 12.79 0.1509 0.30 .Q . . . . 13.08 0.1583 0.31 .Q . . . . 13.37 0.1661 0.33 .Q . . . . 13.66 0.1743 0.35 .Q . . . . 13.95 0.1831 0.38 .Q . . . . 14.25 0.1925 0.40 .Q . . . . 14.54 0.2030 0.46 .Q . . . . 14.83 0.2145 0.49 .Q . . . . 15.12 0.2275 0.58 . Q . . . . 15.42 0.2423 0.65 . Q . . . . 15.71 0.2595 0.78 . Q . . . . 16.00 0.2820 1.08 . Q . . . . 16.29 0.3753 6.64 . . . Q . . 16.58 0.4638 0.70 . Q . . . . 16.88 0.4786 0.53 . Q . . . . 17.17 0.4903 0.44 .Q . . . . 17.46 0.4999 0.36 .Q . . . . 17.75 0.5082 0.32 .Q . . . . 18.05 0.5156 0.29 .Q . . . . 18.34 0.5218 0.22 Q . . . . 18.63 0.5269 0.20 Q . . . . 18.92 0.5317 0.19 Q . . . . 19.21 0.5361 0.18 Q . . . . 19.51 0.5403 0.17 Q . . . . 19.80 0.5442 0.16 Q . . . . 20.09 0.5479 0.15 Q . . . . 20.38 0.5515 0.14 Q . . . . 20.67 0.5549 0.14 Q . . . . 20.97 0.5582 0.13 Q . . . . 21.26 0.5613 0.13 Q . . . . 21.55 0.5644 0.12 Q . . . . 21.84 0.5673 0.12 Q . . . . 22.14 0.5701 0.12 Q . . . . 22.43 0.5729 0.11 Q . . . . 22.72 0.5755 0.11 Q . . . . P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Small Area UH\_ex01.docx 3 of 3 23.01 0.5781 0.11 Q . . . . 23.30 0.5807 0.10 Q . . . . 23.60 0.5831 0.10 Q . . . . 23.89 0.5855 0.10 Q . . . . 24.18 0.5879 0.10 Q . . . . 24.47 0.5890 0.00 Q . . . . ---------------------------------------------------------------------------- -------------------------------------------------------------------------------- TIME DURATION(minutes) OF PERCENTILES OF ESTIMATED PEAK FLOW RATE: (Note: 100% of Peak Flow Rate estimate assumed to have an instantaneous time duration) Percentile of Estimated Duration Peak Flow Rate (minutes) ======================= ========= 0% 1455.0 10% 70.1 20% 17.5 30% 17.5 40% 17.5 50% 17.5 60% 17.5 70% 17.5 80% 17.5 90% 17.5 INFILTRATION LOSS RATE CALCULATIONTTM 17847.Existing Condition.2-Year Event.Loss Rate Calculations: Area-Averaged Low Loss Rate Fraction (Ybar, in/hr) and Area-Averaged Maximum Loss Rate (Fm, in/hr) formulas taken from OCEMA Manual, Section C.ap - See Figure C-4Storm Event Recurrence Interval (Yr) = 2Average ap =0.84Fp - See Table C-2 P24, 25 -Year Storm Event for Non-Mountainous Area (in) = 2.05Total Fm (in/hr) = 0.25CN - See Figure C-1 and C-3 P24, 25 -Year Storm Event for Mountainous Area (in) = 3.810.38Antecedant Moisture Condition (AMC) I, II or III = 1.00Ybar (1-Y) = 0.62- A B CDEF GH I J K L M NOPQR1Area Avg ap2 Land UseLand Use Area Size (Acres)Land Use Area Fraction (Af)Land Use Area Pervious Portion, (ap) (%)Soil GroupapFp (in/hr)Fm (in/hr)(Fm) X (Af) (in/hr)(ap) X (Af)Pervious (P) or Impervious (I).Area (ac)Aj (Area Fraction) Curve NumberSIaYj(Yj) x (Aj)3Value = Cover Type, Cover Condition and % Pervious.Value = 0 to Unlim.Value = Col B / Total Area.Value = 0% to 100% From Col A.Value = "A", "B", "C" or "D".Value = Col D.Values = "A"=0.4, "B"=0.3, "C"=0.25, "D"=0.2Value = Col F x Col G.Value = Col H x Col C.Value = Col F x Col C.P or I.P Value = (B x F). I Value = (B x (1-F)).Value = Col L / Total Area.Value = 0 to 100.Value Per Formula Above.Value Per Formula Above.Value Per Formula Above.Value = Col Q x Col M.4.44 0.4810 97% B 0.97 0.30 0.29 0.1400 0.4666 P 4.31 0.4666 83 2.05 0.41 0.360.166- -------- I 0.130.0144 98 0.20 0.04 0.89 0.0133.45 0.3738 97% B 0.97 0.30 0.29 0.1088 0.3626 P 3.35 0.3626 75 3.33 0.67 0.200.072- -------- I 0.100.0112 98 0.20 0.04 0.89 0.0101.34 0.1452 10% B 0.10 0.30 0.03 0.0044 0.0145 P 0.13 0.0145 83 2.05 0.41 0.360.005- -------- I 1.210.1307 98 0.20 0.04 0.89 0.116- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0Totals = 9.23 1.00 0.25 0.84 9.23 1.00 0.38456141513789121011Y =Area Averaged Maximum Loss Rate (Fm)Area Averaged Low Loss Rate (Ybar)Commercial. Pavement Cover. P=10%. I=90%.Land Use ParametersAgricultural. Fallow Cover. P=97%. I=3%.Equestrian. Fair Cover. P=97%. I=3%.2424224)()(PSIPIPYaaj101000CNSSIa2.0ppmFaFmijAAAAA...21jjmmmAYAAAAYAYAYY......212211P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Soil Loss Calcs\ex 01.xlsx 07 17 181 of 1 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 1 of 12 ____________________________________________________________________________ **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE (Reference: 1986 ORANGE COUNTY HYDROLOGY CRITERION) (c) Copyright 1983-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1355 Analysis prepared by: Fuscoe Engineering 16795 Von Karman Suite 210 Irvine CA 92606 ************************** DESCRIPTION OF STUDY ************************** * MB Arena Site. TTM 17847. * * Proposed Condition Hydrology Calculation. * * 2 Year Frequency. * ************************************************************************** FILE NAME: _P02.DAT TIME/DATE OF STUDY: 11:03 07/17/2018 ============================================================================ USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: ============================================================================ --*TIME-OF-CONCENTRATION MODEL*-- USER SPECIFIED STORM EVENT(YEAR) = 2.00 SPECIFIED MINIMUM PIPE SIZE(INCH) = 18.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.80 *DATA BANK RAINFALL USED* *ANTECEDENT MOISTURE CONDITION (AMC) I ASSUMED FOR RATIONAL METHOD* *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) === ===== ========= ================= ====== ===== ====== ===== ======= 1 30.0 20.0 0.018/0.018/0.020 0.67 2.00 0.0313 0.167 0.0150 GLOBAL STREET FLOW-DEPTH CONSTRAINTS: 1. Relative Flow-Depth = 0.00 FEET as (Maximum Allowable Street Flow Depth) - (Top-of-Curb) 2. (Depth)*(Velocity) Constraint = 3.0 (FT*FT/S) *SIZE PIPE WITH A FLOW CAPACITY GREATER THAN OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.* *USER-SPECIFIED MINIMUM TOPOGRAPHIC SLOPE ADJUSTMENT NOT SELECTED **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 101.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< >>USE TIME-OF-CONCENTRATION NOMOGRAPH FOR INITIAL SUBAREA<< ============================================================================ INITIAL SUBAREA FLOW-LENGTH(FEET) = 64.00 ELEVATION DATA: UPSTREAM(FEET) = 442.30 DOWNSTREAM(FEET) = 440.10 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 2 of 12 Tc = K*[(LENGTH** 3.00)/(ELEVATION CHANGE)]**0.20 SUBAREA ANALYSIS USED MINIMUM Tc(MIN.) = 5.000 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 2.264 SUBAREA Tc AND LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS Tc LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN (MIN.) RESIDENTIAL "1 DWELLING/ACRE" B 0.06 0.30 0.800 36 5.00 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA RUNOFF(CFS) = 0.11 TOTAL AREA(ACRES) = 0.06 PEAK FLOW RATE(CFS) = 0.11 **************************************************************************** FLOW PROCESS FROM NODE 101.00 TO NODE 102.00 IS CODE = 56 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 440.10 DOWNSTREAM(FEET) = 406.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 83.00 CHANNEL SLOPE = 0.4108 GIVEN CHANNEL BASE(FEET) = 3.00 CHANNEL FREEBOARD(FEET) = 1.0 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.02 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 2.191 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.08 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.18 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 4.76 AVERAGE FLOW DEPTH(FEET) = 0.01 TRAVEL TIME(MIN.) = 0.29 Tc(MIN.) = 5.29 SUBAREA AREA(ACRES) = 0.08 SUBAREA RUNOFF(CFS) = 0.14 EFFECTIVE AREA(ACRES) = 0.14 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 0.1 PEAK FLOW RATE(CFS) = 0.25 GIVEN CHANNEL BASE(FEET) = 3.00 CHANNEL FREEBOARD(FEET) = 1.0 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.02 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.02 FLOW VELOCITY(FEET/SEC.) = 4.47 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 102.00 = 147.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 102.00 TO NODE 103.00 IS CODE = 56 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 406.00 DOWNSTREAM(FEET) = 405.90 CHANNEL LENGTH THRU SUBAREA(FEET) = 78.00 CHANNEL SLOPE = 0.0013 GIVEN CHANNEL BASE(FEET) = 1.00 CHANNEL FREEBOARD(FEET) = 1.0 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 3 of 12 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.20 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.927 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.04 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.28 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 0.98 AVERAGE FLOW DEPTH(FEET) = 0.20 TRAVEL TIME(MIN.) = 1.33 Tc(MIN.) = 6.62 SUBAREA AREA(ACRES) = 0.04 SUBAREA RUNOFF(CFS) = 0.06 EFFECTIVE AREA(ACRES) = 0.18 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 0.2 PEAK FLOW RATE(CFS) = 0.27 GIVEN CHANNEL BASE(FEET) = 1.00 CHANNEL FREEBOARD(FEET) = 1.0 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.20 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.20 FLOW VELOCITY(FEET/SEC.) = 1.01 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 103.00 = 225.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 103.00 TO NODE 104.00 IS CODE = 61 ---------------------------------------------------------------------------- >>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>(STANDARD CURB SECTION USED)<<<<< ============================================================================ UPSTREAM ELEVATION(FEET) = 403.00 DOWNSTREAM ELEVATION(FEET) = 401.60 STREET LENGTH(FEET) = 263.00 CURB HEIGHT(INCHES) = 6.0 STREET HALFWIDTH(FEET) = 14.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) = 9.00 INSIDE STREET CROSSFALL(DECIMAL) = 0.017 OUTSIDE STREET CROSSFALL(DECIMAL) = 0.017 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF = 1 STREET PARKWAY CROSSFALL(DECIMAL) = 0.020 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) = 0.0180 Manning's FRICTION FACTOR for Back-of-Walk Flow Section = 0.0200 **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 1.12 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.30 HALFSTREET FLOOD WIDTH(FEET) = 9.68 AVERAGE FLOW VELOCITY(FEET/SEC.) = 1.23 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) = 0.36 STREET FLOW TRAVEL TIME(MIN.) = 3.58 Tc(MIN.) = 10.19 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.504 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 4 of 12 "1 DWELLING/ACRE" B 1.48 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 1.48 SUBAREA RUNOFF(CFS) = 1.68 EFFECTIVE AREA(ACRES) = 1.66 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 1.7 PEAK FLOW RATE(CFS) = 1.89 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH(FEET) = 0.34 HALFSTREET FLOOD WIDTH(FEET) = 12.14 FLOW VELOCITY(FEET/SEC.) = 1.37 DEPTH*VELOCITY(FT*FT/SEC.) = 0.46 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 104.00 = 488.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 104.00 TO NODE 105.00 IS CODE = 61 ---------------------------------------------------------------------------- >>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>(STANDARD CURB SECTION USED)<<<<< ============================================================================ UPSTREAM ELEVATION(FEET) = 401.60 DOWNSTREAM ELEVATION(FEET) = 400.00 STREET LENGTH(FEET) = 317.00 CURB HEIGHT(INCHES) = 6.0 STREET HALFWIDTH(FEET) = 14.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) = 9.00 INSIDE STREET CROSSFALL(DECIMAL) = 0.017 OUTSIDE STREET CROSSFALL(DECIMAL) = 0.017 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF = 1 STREET PARKWAY CROSSFALL(DECIMAL) = 0.020 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) = 0.0180 Manning's FRICTION FACTOR for Back-of-Walk Flow Section = 0.0200 **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 2.38 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.36 HALFSTREET FLOOD WIDTH(FEET) = 13.47 AVERAGE FLOW VELOCITY(FEET/SEC.) = 1.43 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) = 0.52 STREET FLOW TRAVEL TIME(MIN.) = 3.69 Tc(MIN.) = 13.88 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.260 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 1.08 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 1.08 SUBAREA RUNOFF(CFS) = 0.99 EFFECTIVE AREA(ACRES) = 2.74 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 2.7 PEAK FLOW RATE(CFS) = 2.51 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH(FEET) = 0.37 HALFSTREET FLOOD WIDTH(FEET) = 13.82 FLOW VELOCITY(FEET/SEC.) = 1.44 DEPTH*VELOCITY(FT*FT/SEC.) = 0.53 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 105.00 = 805.00 FEET. P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 5 of 12 **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 105.00 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ MAINLINE Tc(MIN.) = 13.88 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.260 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.33 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 0.33 SUBAREA RUNOFF(CFS) = 0.30 EFFECTIVE AREA(ACRES) = 3.07 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 3.1 PEAK FLOW RATE(CFS) = 2.82 **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 106.00 IS CODE = 91 ---------------------------------------------------------------------------- >>>>>COMPUTE "V" GUTTER FLOW TRAVEL TIME THRU SUBAREA<<<<< ============================================================================ UPSTREAM NODE ELEVATION(FEET) = 400.00 DOWNSTREAM NODE ELEVATION(FEET) = 399.80 CHANNEL LENGTH THRU SUBAREA(FEET) = 55.00 "V" GUTTER WIDTH(FEET) = 3.00 GUTTER HIKE(FEET) = 0.100 PAVEMENT LIP(FEET) = 0.010 MANNING'S N = .0130 PAVEMENT CROSSFALL(DECIMAL NOTATION) = 0.02000 MAXIMUM DEPTH(FEET) = 1.00 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.232 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.10 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 2.86 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 1.65 AVERAGE FLOW DEPTH(FEET) = 0.26 FLOOD WIDTH(FEET) = 17.86 "V" GUTTER FLOW TRAVEL TIME(MIN.) = 0.55 Tc(MIN.) = 14.44 SUBAREA AREA(ACRES) = 0.10 SUBAREA RUNOFF(CFS) = 0.09 EFFECTIVE AREA(ACRES) = 3.17 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 3.2 PEAK FLOW RATE(CFS) = 2.83 END OF SUBAREA "V" GUTTER HYDRAULICS: DEPTH(FEET) = 0.26 FLOOD WIDTH(FEET) = 17.86 FLOW VELOCITY(FEET/SEC.) = 1.64 DEPTH*VELOCITY(FT*FT/SEC) = 0.42 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 106.00 = 860.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 106.00 TO NODE 106.00 IS CODE = 10 ---------------------------------------------------------------------------- >>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 <<<<< P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 6 of 12 ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 106.00 TO NODE 106.00 IS CODE = 13 ---------------------------------------------------------------------------- >>>>>CLEAR THE MAIN-STREAM MEMORY<<<<< ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 200.00 TO NODE 201.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< >>USE TIME-OF-CONCENTRATION NOMOGRAPH FOR INITIAL SUBAREA<< ============================================================================ INITIAL SUBAREA FLOW-LENGTH(FEET) = 87.00 ELEVATION DATA: UPSTREAM(FEET) = 437.00 DOWNSTREAM(FEET) = 432.00 Tc = K*[(LENGTH** 3.00)/(ELEVATION CHANGE)]**0.20 SUBAREA ANALYSIS USED MINIMUM Tc(MIN.) = 5.000 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 2.264 SUBAREA Tc AND LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS Tc LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN (MIN.) RESIDENTIAL "1 DWELLING/ACRE" B 0.11 0.30 0.800 36 5.00 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA RUNOFF(CFS) = 0.20 TOTAL AREA(ACRES) = 0.11 PEAK FLOW RATE(CFS) = 0.20 **************************************************************************** FLOW PROCESS FROM NODE 201.00 TO NODE 202.00 IS CODE = 56 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 432.00 DOWNSTREAM(FEET) = 407.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 52.00 CHANNEL SLOPE = 0.4808 GIVEN CHANNEL BASE(FEET) = 1.00 CHANNEL FREEBOARD(FEET) = 1.0 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.03 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 2.232 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.05 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.25 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 6.88 AVERAGE FLOW DEPTH(FEET) = 0.03 TRAVEL TIME(MIN.) = 0.13 Tc(MIN.) = 5.13 SUBAREA AREA(ACRES) = 0.05 SUBAREA RUNOFF(CFS) = 0.09 EFFECTIVE AREA(ACRES) = 0.16 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 0.2 PEAK FLOW RATE(CFS) = 0.29 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 7 of 12 GIVEN CHANNEL BASE(FEET) = 1.00 CHANNEL FREEBOARD(FEET) = 1.0 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.04 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.04 FLOW VELOCITY(FEET/SEC.) = 7.59 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 202.00 = 139.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 202.00 TO NODE 203.00 IS CODE = 56 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 407.00 DOWNSTREAM(FEET) = 406.90 CHANNEL LENGTH THRU SUBAREA(FEET) = 196.00 CHANNEL SLOPE = 0.0005 GIVEN CHANNEL BASE(FEET) = 1.00 CHANNEL FREEBOARD(FEET) = 1.0 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.44 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.644 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.55 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.64 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 0.91 AVERAGE FLOW DEPTH(FEET) = 0.39 TRAVEL TIME(MIN.) = 3.60 Tc(MIN.) = 8.73 SUBAREA AREA(ACRES) = 0.55 SUBAREA RUNOFF(CFS) = 0.70 EFFECTIVE AREA(ACRES) = 0.71 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 0.7 PEAK FLOW RATE(CFS) = 0.90 GIVEN CHANNEL BASE(FEET) = 1.00 CHANNEL FREEBOARD(FEET) = 1.0 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 *ESTIMATED CHANNEL HEIGHT(FEET) = 1.47 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.47 FLOW VELOCITY(FEET/SEC.) = 0.99 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 203.00 = 335.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 203.00 TO NODE 203.00 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ MAINLINE Tc(MIN.) = 8.73 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.644 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.66 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 8 of 12 SUBAREA AREA(ACRES) = 0.66 SUBAREA RUNOFF(CFS) = 0.83 EFFECTIVE AREA(ACRES) = 1.37 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 1.4 PEAK FLOW RATE(CFS) = 1.73 **************************************************************************** FLOW PROCESS FROM NODE 203.00 TO NODE 204.00 IS CODE = 61 ---------------------------------------------------------------------------- >>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>(STANDARD CURB SECTION USED)<<<<< ============================================================================ UPSTREAM ELEVATION(FEET) = 403.00 DOWNSTREAM ELEVATION(FEET) = 402.00 STREET LENGTH(FEET) = 193.00 CURB HEIGHT(INCHES) = 6.0 STREET HALFWIDTH(FEET) = 18.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) = 13.00 INSIDE STREET CROSSFALL(DECIMAL) = 0.017 OUTSIDE STREET CROSSFALL(DECIMAL) = 0.017 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF = 1 STREET PARKWAY CROSSFALL(DECIMAL) = 0.020 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) = 0.0180 Manning's FRICTION FACTOR for Back-of-Walk Flow Section = 0.0200 **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 2.33 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.36 HALFSTREET FLOOD WIDTH(FEET) = 13.28 AVERAGE FLOW VELOCITY(FEET/SEC.) = 1.44 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) = 0.51 STREET FLOW TRAVEL TIME(MIN.) = 2.24 Tc(MIN.) = 10.97 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.442 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 1.10 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 1.10 SUBAREA RUNOFF(CFS) = 1.19 EFFECTIVE AREA(ACRES) = 2.47 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 2.5 PEAK FLOW RATE(CFS) = 2.67 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH(FEET) = 0.37 HALFSTREET FLOOD WIDTH(FEET) = 14.09 FLOW VELOCITY(FEET/SEC.) = 1.48 DEPTH*VELOCITY(FT*FT/SEC.) = 0.55 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 204.00 = 528.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 204.00 TO NODE 205.00 IS CODE = 61 ---------------------------------------------------------------------------- >>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>(STANDARD CURB SECTION USED)<<<<< ============================================================================ UPSTREAM ELEVATION(FEET) = 402.00 DOWNSTREAM ELEVATION(FEET) = 401.00 STREET LENGTH(FEET) = 195.00 CURB HEIGHT(INCHES) = 6.0 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 9 of 12 STREET HALFWIDTH(FEET) = 18.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) = 13.00 INSIDE STREET CROSSFALL(DECIMAL) = 0.017 OUTSIDE STREET CROSSFALL(DECIMAL) = 0.017 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF = 1 STREET PARKWAY CROSSFALL(DECIMAL) = 0.020 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) = 0.0180 Manning's FRICTION FACTOR for Back-of-Walk Flow Section = 0.0200 **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 3.20 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.39 HALFSTREET FLOOD WIDTH(FEET) = 15.21 AVERAGE FLOW VELOCITY(FEET/SEC.) = 1.53 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) = 0.60 STREET FLOW TRAVEL TIME(MIN.) = 2.12 Tc(MIN.) = 13.09 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.303 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 1.10 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 1.10 SUBAREA RUNOFF(CFS) = 1.05 EFFECTIVE AREA(ACRES) = 3.57 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 3.6 PEAK FLOW RATE(CFS) = 3.42 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH(FEET) = 0.40 HALFSTREET FLOOD WIDTH(FEET) = 15.61 FLOW VELOCITY(FEET/SEC.) = 1.56 DEPTH*VELOCITY(FT*FT/SEC.) = 0.62 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 205.00 = 723.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 206.00 IS CODE = 61 ---------------------------------------------------------------------------- >>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>(STANDARD CURB SECTION USED)<<<<< ============================================================================ UPSTREAM ELEVATION(FEET) = 401.00 DOWNSTREAM ELEVATION(FEET) = 399.80 STREET LENGTH(FEET) = 208.00 CURB HEIGHT(INCHES) = 6.0 STREET HALFWIDTH(FEET) = 18.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) = 13.00 INSIDE STREET CROSSFALL(DECIMAL) = 0.017 OUTSIDE STREET CROSSFALL(DECIMAL) = 0.017 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF = 1 STREET PARKWAY CROSSFALL(DECIMAL) = 0.020 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) = 0.0180 Manning's FRICTION FACTOR for Back-of-Walk Flow Section = 0.0200 **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 3.83 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 10 of 12 STREET FLOW DEPTH(FEET) = 0.40 HALFSTREET FLOOD WIDTH(FEET) = 15.92 AVERAGE FLOW VELOCITY(FEET/SEC.) = 1.69 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) = 0.68 STREET FLOW TRAVEL TIME(MIN.) = 2.06 Tc(MIN.) = 15.14 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.198 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.97 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 0.97 SUBAREA RUNOFF(CFS) = 0.84 EFFECTIVE AREA(ACRES) = 4.54 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 4.5 PEAK FLOW RATE(CFS) = 3.92 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH(FEET) = 0.40 HALFSTREET FLOOD WIDTH(FEET) = 16.02 FLOW VELOCITY(FEET/SEC.) = 1.70 DEPTH*VELOCITY(FT*FT/SEC.) = 0.69 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 206.00 = 931.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 206.00 TO NODE 206.00 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY<<<<< ============================================================================ ** MAIN STREAM CONFLUENCE DATA ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 3.92 15.14 1.198 0.30( 0.24) 0.80 4.5 200.00 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 206.00 = 931.00 FEET. ** MEMORY BANK # 1 CONFLUENCE DATA ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 2.83 14.44 1.232 0.30( 0.24) 0.80 3.2 100.00 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 206.00 = 860.00 FEET. ** PEAK FLOW RATE TABLE ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 6.69 14.44 1.232 0.30( 0.24) 0.80 7.5 100.00 2 6.65 15.14 1.198 0.30( 0.24) 0.80 7.7 200.00 TOTAL AREA(ACRES) = 7.7 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 6.69 Tc(MIN.) = 14.436 EFFECTIVE AREA(ACRES) = 7.50 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 7.7 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 206.00 = 931.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 206.00 TO NODE 206.00 IS CODE = 12 P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 11 of 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 <<<<< ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 206.00 TO NODE 207.00 IS CODE = 61 ---------------------------------------------------------------------------- >>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>(STANDARD CURB SECTION USED)<<<<< ============================================================================ UPSTREAM ELEVATION(FEET) = 399.80 DOWNSTREAM ELEVATION(FEET) = 399.05 STREET LENGTH(FEET) = 221.00 CURB HEIGHT(INCHES) = 6.0 STREET HALFWIDTH(FEET) = 18.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) = 13.00 INSIDE STREET CROSSFALL(DECIMAL) = 0.017 OUTSIDE STREET CROSSFALL(DECIMAL) = 0.017 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF = 2 STREET PARKWAY CROSSFALL(DECIMAL) = 0.020 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) = 0.0180 Manning's FRICTION FACTOR for Back-of-Walk Flow Section = 0.0200 **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 6.89 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.42 HALFSTREET FLOOD WIDTH(FEET) = 16.93 AVERAGE FLOW VELOCITY(FEET/SEC.) = 1.35 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) = 0.56 STREET FLOW TRAVEL TIME(MIN.) = 2.74 Tc(MIN.) = 17.17 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.115 SUBAREA LOSS RATE DATA(AMC I ): DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.50 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 0.50 SUBAREA RUNOFF(CFS) = 0.39 EFFECTIVE AREA(ACRES) = 8.00 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 8.2 PEAK FLOW RATE(CFS) = 6.69 NOTE: PEAK FLOW RATE DEFAULTED TO UPSTREAM VALUE END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH(FEET) = 0.42 HALFSTREET FLOOD WIDTH(FEET) = 16.73 FLOW VELOCITY(FEET/SEC.) = 1.34 DEPTH*VELOCITY(FT*FT/SEC.) = 0.56 LONGEST FLOWPATH FROM NODE 200.00 TO NODE 207.00 = 1152.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 207.00 TO NODE 207.00 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ MAINLINE Tc(MIN.) = 17.17 * 2 YEAR RAINFALL INTENSITY(INCH/HR) = 1.115 SUBAREA LOSS RATE DATA(AMC I ): P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Rational Method\2 Yr\_p02.docx 12 of 12 DEVELOPMENT TYPE/ SCS SOIL AREA Fp Ap SCS LAND USE GROUP (ACRES) (INCH/HR) (DECIMAL) CN RESIDENTIAL "1 DWELLING/ACRE" B 0.95 0.30 0.800 36 SUBAREA AVERAGE PERVIOUS LOSS RATE, Fp(INCH/HR) = 0.30 SUBAREA AVERAGE PERVIOUS AREA FRACTION, Ap = 0.800 SUBAREA AREA(ACRES) = 0.95 SUBAREA RUNOFF(CFS) = 0.75 EFFECTIVE AREA(ACRES) = 8.95 AREA-AVERAGED Fm(INCH/HR) = 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.80 TOTAL AREA(ACRES) = 9.2 PEAK FLOW RATE(CFS) = 7.05 ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 9.2 TC(MIN.) = 17.17 EFFECTIVE AREA(ACRES) = 8.95 AREA-AVERAGED Fm(INCH/HR)= 0.24 AREA-AVERAGED Fp(INCH/HR) = 0.30 AREA-AVERAGED Ap = 0.800 PEAK FLOW RATE(CFS) = 7.05 ** PEAK FLOW RATE TABLE ** STREAM Q Tc Intensity Fp(Fm) Ap Ae HEADWATER NUMBER (CFS) (MIN.) (INCH/HR) (INCH/HR) (ACRES) NODE 1 7.05 17.17 1.115 0.30( 0.24) 0.80 8.9 100.00 2 7.00 17.90 1.089 0.30( 0.24) 0.80 9.2 200.00 ============================================================================ ============================================================================ END OF RATIONAL METHOD ANALYSIS P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Small Area UH\_pr01.docx 1 of 3 ____________________________________________________________________________ **************************************************************************** SMALL AREA UNIT HYDROGRAPH MODEL ============================================================================ (C) Copyright 1989-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1355 Analysis prepared by: Fuscoe Engineering 16795 Von Karman Suite 210 Irvine CA 92606 **************************************************************************** ---------------------------------------------------------------------------- Problem Descriptions: MB Arena Site. TTM 17847. Proposed Condition Runoff Volume Calculation. 2 Year Frequency. ---------------------------------------------------------------------------- RATIONAL METHOD CALIBRATION COEFFICIENT = 0.89 TOTAL CATCHMENT AREA(ACRES) = 9.16 SOIL-LOSS RATE, Fm,(INCH/HR) = 0.240 LOW LOSS FRACTION = 0.540 TIME OF CONCENTRATION(MIN.) = 17.17 SMALL AREA PEAK Q COMPUTED USING PEAK FLOW RATE FORMULA ORANGE COUNTY "VALLEY" RAINFALL VALUES ARE USED RETURN FREQUENCY(YEARS) = 2 5-MINUTE POINT RAINFALL VALUE(INCHES) = 0.19 30-MINUTE POINT RAINFALL VALUE(INCHES) = 0.40 1-HOUR POINT RAINFALL VALUE(INCHES) = 0.53 3-HOUR POINT RAINFALL VALUE(INCHES) = 0.89 6-HOUR POINT RAINFALL VALUE(INCHES) = 1.22 24-HOUR POINT RAINFALL VALUE(INCHES) = 2.05 ---------------------------------------------------------------------------- TOTAL CATCHMENT RUNOFF VOLUME(ACRE-FEET) = 0.70 TOTAL CATCHMENT SOIL-LOSS VOLUME(ACRE-FEET) = 0.86 **************************************************************************** TIME VOLUME Q 0. 2.5 5.0 7.5 10.0 (HOURS) (AF) (CFS) ---------------------------------------------------------------------------- 0.26 0.0013 0.12 Q . . . . 0.55 0.0041 0.12 Q . . . . 0.83 0.0070 0.12 Q . . . . 1.12 0.0099 0.12 Q . . . . 1.41 0.0129 0.13 Q . . . . 1.69 0.0158 0.13 Q . . . . 1.98 0.0189 0.13 Q . . . . 2.26 0.0219 0.13 Q . . . . 2.55 0.0250 0.13 Q . . . . P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Small Area UH\_pr01.docx 2 of 3 2.84 0.0281 0.13 Q . . . . 3.12 0.0313 0.14 Q . . . . 3.41 0.0345 0.14 Q . . . . 3.69 0.0378 0.14 Q . . . . 3.98 0.0411 0.14 Q . . . . 4.27 0.0445 0.14 Q . . . . 4.55 0.0479 0.14 Q . . . . 4.84 0.0513 0.15 Q . . . . 5.13 0.0549 0.15 Q . . . . 5.41 0.0584 0.15 Q . . . . 5.70 0.0621 0.15 Q . . . . 5.98 0.0658 0.16 Q . . . . 6.27 0.0695 0.16 Q . . . . 6.56 0.0734 0.16 Q . . . . 6.84 0.0773 0.17 Q . . . . 7.13 0.0812 0.17 Q . . . . 7.41 0.0853 0.17 Q . . . . 7.70 0.0894 0.18 Q . . . . 7.99 0.0937 0.18 Q . . . . 8.27 0.0980 0.19 Q . . . . 8.56 0.1024 0.19 Q . . . . 8.85 0.1069 0.19 Q . . . . 9.13 0.1116 0.20 Q . . . . 9.42 0.1163 0.20 Q . . . . 9.70 0.1212 0.21 Q . . . . 9.99 0.1262 0.22 Q . . . . 10.28 0.1314 0.22 Q . . . . 10.56 0.1367 0.23 Q . . . . 10.85 0.1422 0.23 Q . . . . 11.14 0.1479 0.25 Q . . . . 11.42 0.1537 0.25 .Q . . . . 11.71 0.1598 0.26 .Q . . . . 11.99 0.1662 0.27 .Q . . . . 12.28 0.1735 0.35 .Q . . . . 12.57 0.1819 0.36 .Q . . . . 12.85 0.1906 0.38 .Q . . . . 13.14 0.1998 0.39 .Q . . . . 13.42 0.2094 0.42 .Q . . . . 13.71 0.2196 0.44 .Q . . . . 14.00 0.2305 0.48 .Q . . . . 14.28 0.2422 0.51 . Q . . . . 14.57 0.2552 0.58 . Q . . . . 14.86 0.2695 0.62 . Q . . . . 15.14 0.2855 0.74 . Q . . . . 15.43 0.3039 0.82 . Q . . . . 15.71 0.3253 0.99 . Q . . . . 16.00 0.3532 1.37 . Q . . . . 16.29 0.4528 7.05 . . . Q . . 16.57 0.5464 0.87 . Q . . . . 16.86 0.5647 0.67 . Q . . . . 17.14 0.5791 0.55 . Q . . . . 17.43 0.5911 0.46 .Q . . . . 17.72 0.6013 0.41 .Q . . . . 18.00 0.6105 0.37 .Q . . . . 18.29 0.6182 0.28 .Q . . . . 18.58 0.6245 0.26 .Q . . . . 18.86 0.6304 0.24 Q . . . . P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Small Area UH\_pr01.docx 3 of 3 19.15 0.6359 0.22 Q . . . . 19.43 0.6411 0.21 Q . . . . 19.72 0.6459 0.20 Q . . . . 20.01 0.6506 0.19 Q . . . . 20.29 0.6550 0.18 Q . . . . 20.58 0.6592 0.18 Q . . . . 20.86 0.6633 0.17 Q . . . . 21.15 0.6672 0.16 Q . . . . 21.44 0.6710 0.16 Q . . . . 21.72 0.6746 0.15 Q . . . . 22.01 0.6781 0.15 Q . . . . 22.30 0.6815 0.14 Q . . . . 22.58 0.6848 0.14 Q . . . . 22.87 0.6881 0.13 Q . . . . 23.15 0.6912 0.13 Q . . . . 23.44 0.6942 0.13 Q . . . . 23.73 0.6972 0.12 Q . . . . 24.01 0.7001 0.12 Q . . . . 24.30 0.7016 0.00 Q . . . . ---------------------------------------------------------------------------- ----------------------------------------------------------------------------- --- TIME DURATION(minutes) OF PERCENTILES OF ESTIMATED PEAK FLOW RATE: (Note: 100% of Peak Flow Rate estimate assumed to have an instantaneous time duration) Percentile of Estimated Duration Peak Flow Rate (minutes) ======================= ========= 0% 1442.3 10% 103.0 20% 17.2 30% 17.2 40% 17.2 50% 17.2 60% 17.2 70% 17.2 80% 17.2 90% 17.2 INFILTRATION LOSS RATE CALCULATIONTTM 17847.Proposed Condition.2-Year Event.Loss Rate Calculations: Area-Averaged Low Loss Rate Fraction (Ybar, in/hr) and Area-Averaged Maximum Loss Rate (Fm, in/hr) formulas taken from OCEMA Manual, Section C.ap - See Figure C-4Storm Event Recurrence Interval (Yr) = 2Average ap =0.80Fp - See Table C-2 P24, 25 -Year Storm Event for Non-Mountainous Area (in) = 2.05Total Fm (in/hr) = 0.24CN - See Figure C-1 and C-3 P24, 25 -Year Storm Event for Mountainous Area (in) = 3.810.46Antecedant Moisture Condition (AMC) I, II or III = 1.00Ybar (1-Y) = 0.54- A B CDEF GH I J K L M NOPQR1Area Avg ap2 Land UseLand Use Area Size (Acres)Land Use Area Fraction (Af)Land Use Area Pervious Portion, (ap) (%)Soil GroupapFp (in/hr)Fm (in/hr)(Fm) X (Af) (in/hr)(ap) X (Af)Pervious (P) or Impervious (I).Area (ac)Aj (Area Fraction) Curve NumberSIaYj(Yj) x (Aj)3Value = Cover Type, Cover Condition and % Pervious.Value = 0 to Unlim.Value = Col B / Total Area.Value = 0% to 100% From Col A.Value = "A", "B", "C" or "D".Value = Col D.Values = "A"=0.4, "B"=0.3, "C"=0.25, "D"=0.2Value = Col F x Col G.Value = Col H x Col C.Value = Col F x Col C.P or I.P Value = (B x F). I Value = (B x (1-F)).Value = Col L / Total Area.Value = 0 to 100.Value Per Formula Above.Value Per Formula Above.Value Per Formula Above.Value = Col Q x Col M.9.16 1.0000 80% B 0.80 0.30 0.24 0.2400 0.8000 P 7.33 0.8000 83 2.05 0.41 0.360.285- -------- I 1.830.2000 98 0.20 0.04 0.89 0.178- 0% B 0.00 0.30 0.00 - - P 0.00 - 75 - - - 0- -------- I 0.00- 98---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 83 - - - 0- -------- I 0.00- 98---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0- 0% B 0.00 0.30 0.00 - - P 0.00 - 0 - - - 0- -------- I 0.00- 0---0Totals = 9.16 1.00 0.24 0.80 9.16 1.00 0.46Y =Area Averaged Maximum Loss Rate (Fm)Area Averaged Low Loss Rate (Ybar)Land Use ParametersResidential. 1du/ac. P=80%. I=20%.1415137891210114562424224)()(PSIPIPYaaj101000CNSSIa2.0ppmFaFmijAAAAA...21jjmmmAYAAAAYAYAYY......212211P:\Projects\881\03\Eng\Admin\Reports\WQMP\Hydrowin Calcs\Soil Loss Calcs\pr 01.xlsx 07 17 181 of 1