RES-8823 Approving the Residential Neighborhood Traffic Management ProgramRESOLUTION NO. 8823
A RESOLUTION OF THE CITY COUNCIL OF THE
CITY OF ORANGE APPROVING THE
RESIDENTIAL NEIGHBORHOOD TRAFFIC
MANAGEMENT PROGRAM".
WHEREAS, the City of Orange is committed to the safety and livability of residential
neighborhoods; and
WHEREAS, the City has been receIVIng, in recent years, numerous concerns and
complaints regarding a variety of related problems within residential neighborhoods; and
WHEREAS, the City desires to have a consistent approach to deal with the traffic issues
in residential neighborhoods.
NOW, THEREFORE, BE IT RESOLVED by the City Council of the City of Orange
as follows:
Section I:
That the attached "Residential Neighborhood Traffic Management Program" is the City's
policy for managing traffic related issues on residential streets.
Section II:
That the design parameters and guidelines established in the "Residential Neighborhood
Traffic Management Program" are the City's standards for the installation of those devices.
ADOPTED this ~ day of December, 1997.
of Orange
ATTEST:
City Clerk of the City of Orange
I hereby certifY that the foregoing Resolution was duly and regularly adopted by the City
Council of the City of Orange at a regular meeting thereof held on the this ~ day of
December. 1997, by the following vote:
AYES: COUNCIL MEMBERS: Murphy, Slater, Coontz, spurgeon, Alvarez
NOES: COUNCIL MEMBERS: None
ABSENT: COUNCIL MEMBERS: None
ABSTAIN: councilmembers; None
t1uAM~--V -it Ct/ ..//'~
Cassandra 1. Cath rt, CIty Clerk of the CIty of Orange
Reso. No. 8823
Prepared By: Public Works Dept
Typed By: P. Then
eJ R-8823 [N:
CITY OF OR.\:"GE
30n Ii. Chapm:m Ave.
Orange. CA_ 92866
Phone (714) 744--
5536 Fax (714)
744--6961 Traffic
Engineering Division
Residential Neighborhood Traffic
Management Program for the City
of Orange
December
1997 Q
c.; _ Y\Mayor
Joanne Coontz Mayor ProTem
Dan Slater Councilman
Mike Spurgeon Councilman
Mark Murphy Councilman
Mike Alvarez City of Orange Commits to the Safety
and Livability of
Residential Neighborhoods.Prepared and
Recommended
By:City Traffic
Engineer David L.
Rudat City
Residential Neighborhood Traffic
Management Program
for the City of Orange
Introduction ------------------------------------------------------------------------ 2 Program
Objectives---------------------------------------------------------------- 4 Program
Policies------------------------------------------------------------------- 5 Thresholds --------------------------------------------------------------------------
7 Procedures-------------------------------------------------------------------------10
Speed
Humps ---------------------------------------------------------------------15 TrafIic <:
ircles---------------------------------------------------------------------17
N arrowings ------------------------------------------------------------------------ 20 I>
iverters---------------------------------------------------------------------------22
Offset - N arrowings---------------------------------------------------------------- 24 Neighborhood
Traffic Watch ---------------------------------------------------- 25 VideolPhoto Enforcement -------------------------------------------------------
27 Speed Wagon/
Radar Trailers ----------------------------------------------------29 I>river
Education ----------------------------------------------------------------- 3 0 Selective Police Enforcement ---------------------------------------------------
31 Slow Points------------------------------------------------------------------------ 32
Residential Neighborhood
Traffic Management Plan
for the City of Orange
The City has been receIVIng, In recent years, numerous concerns and
complaints regarding a variety of traffic related problems mostly within
residential neighborhoods. These concerns are generally regarding perceived
excessive speeds and at times are focused on high traffic volumes or number of
accidents. These characteristics mostly have their root causes in issues such as
urban sprawl, unmitigated densification of land uses, population growth and
sociaVcultural trends in the society which are obviously beyond the domain of
conventional municipal traffic engineering. Nevertheless, traffic professionals
over the years have developed techniques to reduce the negative impacts of
such problems in urban settings. This program, prepared for the City of
Orange, has been developed through a comprehensive survey and evaluation of
similar efforts in other municipalities in North America (U.S. and Canada),
Western Europe and Australia. Some of the material presented in this report is
drawn from similar documents prepared for those municipalities. Obviously,
each community must carefully evaluate and choose only those techniques that
are suitable for their needs and will enjoy public support.
Page 2 FileName: RN1MProgram
Disk #19\Thenp
This report provides a "Tool Box" of traffic management and traffic calming
measures identifying each technique's advantages and disadvantages,
establishing general design parameters (where possible), and
policies/procedures for their implementation.
The following is a list of techniques/measures evaluated and presented in this
report:
1. Speed Humps
2. Traffic Circles
3. Narrowings (mid-block or at
intersections)4. Diverters (partial or full) [turn-
restriction signs]5. Offset narrowings
of streets 6. Neighborhood
Traffic Watch 7.
VideolPhoto Enforcement 8.
Speed WagonlTrailer 9.
Driver Education 10. Selective
Traffic Enforcement 11. Slow Points (mid-
block and intersection)Conventional passive types of control such as speed limit
signs are already regulated by State laws and are not presented here.
Also, regulatory traffic control devices such as traffic signals and STOP signs serve
a different purpose Page 3 File
Name: RN1M Program
and their use for traffic management/calming is strongly discouraged by federal
and state guidelines such as the Manual for Uniform Traffic Control Devices
MUTCD) [Section 2B-
5].Full street closures are not discussed in detail in this report. Such
drastic measures are strongly discouraged due to their many adverse impacts.
Any street closure project must be programmed and evaluated individually
going through full environmental clearance and budget appropriation
processes.The overall objectives of the Program are derived from existing City policy
and are as
follows:1. Encourage through traffic to use higher classification
arterials,as designated on the City's Master Plan of Streets &
Highways.2. Improve neighborhood livability by mitigating the
adverse impacts of vehicular traffic on residential neighborhoods; i.
e.,noise, air pollution, safety,
etc.3. Promote safe and pleasant conditions for residents,
motorists,bicyclists, and pedestrians on residential
streets.4. Encourage and incorporate citizen participation in all phases
of Traffic Management/Calming Program
activities.Page 4 File Name: RN1M
Program Disk # 19\
5. Make efficient use of City resources by prioritizing projects.
6. Reduce collision frequency and severity.
7. Maximize the use of self-enforcing
measures.The following policies are established to guide the staff, the community and
the policy-makers in selecting the appropriate measures for each
individual case.1. A combination of education, enforcement,
and engineering methods should be employed. Appropriate measures
should be planned and designed in keeping with sound
engineering and planning practices. The City Traffic Engineer shall
direct the installation of devices as needed to accomplish the
project, in compliance with the municipal code,
and acceptable professional traffic
engineering practices.2. Emergency vehicle access should be
accommodated consistent with response standards. If current emergency
vehicle access does not meet the existing response standard,
traffic calming efforts should not further degrade the
response time.3. Transit service and school bus access, safety,
and scheduling should not be
significantly impacted.Page 5
FileName: RNIMProgram Disk #
4. Reasonable automobile access should be maintained.
Pedestrian, bicycle, and transit access should be encouraged and
enhanced wherever possible within budget limitations.
5. Parking removal should be considered on a project-
by-project basis. Parking needs of residents should be balanced
with the equally important functions of traffic, emergency
vehicle access,transit, bicycle, and pedestrian movement. However,
it should be acknowledged that the implementation of many of
the traffic calming measures will require elimination of
on-
street parking spaces.6. Application of the Program shall be
limited to those neighborhood streets that are within a "
residence district" as defined by the California Vehicle Code (CVe)
Sections
240 and 515.7. Traffic may be rerouted from one local street to
another as a result of a traffic calming project.
The acceptable traffic diversion should be defined on
a project-by-project basis.8. To implement the
Program, certain procedures should be followed by the
Traffic Engineering Division in processmg traffic calming requests in
accordance with applicable codes and related policies within the limits
of available resources. At
a Page 6
minimum, the procedures (defined later in this report) shall
provide for submittal of project proposals, project evaluation
and selection, citizen participation, communication of any test
results and specific findings to project area residents and
affected organizations and appropriate City Traffic Commission
and City Council review and approvals before installation of
permanent traffic calming devices.
9. The potential increased liability to the City associated with the
installation of such measures should be assessed by the City
Attorney on a project-by-
project basis.10. Cost sharing options between City and the area
residents must be seriously considered for the implementation
of the recommended measures, especially for any
unfunded projects.In order to maximize the benefits of this Program through
effective allocation of personnel and financial resources to address "real" needs,
the "candidate"street (or streets) must meet certain conditions before the
City considers initiation of any traffic management/
calming study.Page 7 File Name:
RNIM Progmm Disk #
Candidate street(s) shall meet all of the following requirements:
a) Street must not be more than one lane in each direction.
b) Street must not be wider than 40 feet, curb-
to-curb.c) Street must not be on the City's Master Plan of Streets &
Highways or on the County's Master Plan of
Arterial Highways.d) Street must not be on an established Orange County
Transit District Route as adopted by the
OCT A.e) Street must be in a "residence district" as defined by Sections
240 and 515 of the California Vehicle
Code (CVC).In addition to meeting all of the above conditions, the candidate street(
s) must meet at least one of the following criteria
as well:a) The 85th percentile speed of traffic (as measured for
an average weekday for a period of one-hour during off-peak
hours) must be equal to or greater than 33
miles per hour (MPR).b) The average daily traffic volume (measured
by averaging 3-day count from Tuesday through Thursday) must be at
least 2,500 vehicles, total in both
directions, in a 24-hour period.c) The accident rate for the
candidate street during the 12-month period preceding the date of the
study must be greater than
the "Expected PageS
Accident Rate" for such a roadway as established by the California
Department of Transportation.
Should any emergency response station (police or Fire) be contiguous to the
Candidate Street(s) and have direct access to the street(s), the installation of
any traffic management/calming measure will only be considered subject to a
written approval from that department (police or Fire).
Page 9 File Name: RN1M Program
Disk # 19\Thenp
The procedures specified in this section are the City's policy for processing
traffic related requests in residential neighborhoods. Any special cases or
requests not foreseen in these procedures, will be determined administratively
by the City Traffic Engineer. These procedures complement the City's
Municipal Code, Ordinances and Council Resolutions and do not supersede
them. In the case of any apparent conflict, those shall prevail over this policy.
1. Initial request should be made by the resident( s) in writing,
explaining their specific concerns and identiIYing their requested
device(s), if any.
2. The applicant shall be provided information regarding City's
Residential Neighborhood Traffic Management Program as a
handout package. This package will be prepared and updated
by Traffic Engineering Division staff and not exceed 4 pages.
3. If the streets encompassed by the applicant's request meet the
minimum criteria established in the "Threshold" section of this
report, staff will advise the applicant of the initiation of a
Residential Neighborhood Traffic Management Program"
study. Staff will collect the necessary field data such as the
average daily traffic volume and traffic speed information as
part of this eligibility determination.
Page 10 FileName: RNlMPmgnun
Disk # 19\Thenp
4. If the included street(s) meets the requirements in the
Threshold" section of this report, Traffic Engineering Division
staff will evaluate the field conditions and recommend
appropriate traffic management/calming measure(s) as described
in this policy. The City Traffic Engineer will review and
approve the staffrecommendation{s). The applicant(s) will then
be notified of the staff's recommendation{s). If the applicant(s)
disagree(s) with the staff's findings, he may request that the
project be presented to the City Traffic Commission for their
review and recommendation.
5. If the applicant(s) agree{s) with staff's recommendation(s) and
decide(s) to pursue further, staff will prepare a petition for the
study area (which could be one or more streets) and send it to
the applicant(s) via certified mail. The petition will briefly
outline the staff recommendation{ s) and the City's program and
policies regarding installation and removal of traffic
management/calming measures and the costs associated with
them. Each household is allowed one signature which must be
that of the head of household.
6. Seventy-five percent (75%) of all the households in the
study must sign the petition in favor of the staff's recommendation{
s)acknowledging the implications of the installation of
the Page II FileName:
RNIMProgram Disk # 19\
proposed devices. The petition will clearly state staff's (or the
CTC's) recommendation and will indicate the location of any
proposed devices, i.e., speed humps. This information will be
shown on every individual signature page of the petition. The
placement of calming devices is a technical decision that should
be made by the City Traffic Engineer and is not contingent upon
consent of adjacent property owner( s )Iresident(s).
Applicant{s) will be given 45 calendar days (from the date the
petition is mailed by the City) to complete the petition and
return it to the City. Failure to accomplish this will terminate
the process, and any further requests (even on the same streets)
will require another eligibility check by staff as prescribed in this
section. All attempts should be made to ensure that all
households within the study area are given the opportunity to
review and sign the petition.
7. Upon the receipt of the completed petition (meeting
requirements specified in Items 5 and 6 herein), staff will
present the project to the City Traffic Commission for review
and approval.
8. Only those recommendations of the City Traffic Commission
which require the City Council's action (as specified in the
Orange Municipal Code Section 10.06.080) will be presented to
Page 12 FileName: RNIMPrognun
Disk # 19\Thenp
the City Council for review and approval.All other
recommendations of the City Traffic Commission will be
implemented after the expiration of the appeal period (15 days
after the Commission hearing date).
9. The City Traffic Commission (or City Council)
recommendations will be installed on either temporary (trial) or
permanent basis as directed by the Commission or the Council.
10. Any request for removal of the newly installed devices must be
accompanied with a petition meeting the requirements specified
in Item 5 of this section. Eighty percent (80%) of all the
households in the study area must sign the petition in favor of
the removal of devices. If the devices are installed on a
temporary (trial) basis, no removal petition will be accepted
during the test period as specified by the Commission or the
Council.
11. Removal petitions will be presented to the City Traffic
Commission for review and recommendation. City Traffic
Commission action regarding removal of devices will be final
unless appealed to the City Council.
12. City considers staff time associated with processmg such
requests as legitimate expenditures promoting public interest at
Page 13 File Name: RNfM Prognun
Disk #19\Thenp
large and does not reqUire an application fee for either
installation or removal (if the devices are installed on temporary
basis as directed by the Councilor the CTe) requests.
However, this fee waiver applies only to first time requests.
Any follow-up requests on the same streets (made after
devices are installed on permanent basis or are removed according
to these procedures) will be subject to application fees of $2,
650 and $2,170 for installation and removal requests,
respectively.Those fees will be due after staff's determination of a street'
s eligibility according the requirements established in
the Threshold" section of this
report.13. All clarifications or administrative interpretations of
these procedures will be made by the City Traffic
Engineer.Page 14 File Name: RN1M
Program Disk # 19\
Speed Humps:
Speed Humps are usually constructed as "Single-Curvature" or "Flat
Top".Flat Top" configuration is also referred to as a "Speed Bed"). The "
Single Curvature" speed hump is a gradual rise and fall of the street profile in
the direction of travel shaped as a single parabolic curve (see Exhibit 2). The "
Flat Top" speed hump is a gradual rise in the street profile, in the direction
of travel, through a parabolic curve followed by an elevated section and then a
fall back to the normal profile through a second parabolic curve (see Exhibit
3).Either of the two configurations can be designed and constructed
safely.Speed humps have been proven to be very effective in reducing traffic
speeds,if designed and installed appropriately. A typical plan view of a speed hump
is shown in Exhibit
1.ADVANTAGES
DISADVANTAGES Effectively reduce traffic speeds . Can possibly increase
traffic Do not require parking removal noise from braking and
acceleration Pose no restrictions for bicycles of vehicles, particularly busses
and Do not affect intersection operation
trucks.Speed humps, Single Curvature or Flat Top, can be designed and
constructed according to Exhibits 2 and 3, respectively. The City Traffic Engineer,
in consultation with the adjacent community, will determine the type of
speed hump which is more appropriate on a project-
by-project basis.Page 15 File
Name: RNlM Program
COST: Approximately $3,000 per undulation for "Single Curvature", and
5,000 for the "Flat Top" per installation.
The placement of speed humps shall be in conformance with the following
guidelines:
1. The grade of the roadway shall not exceed five percent within
200 feet of the speed hump.
2. There shall be no public or private street intersections within
150 feet of the proposed location of speed humps.
3. There shall be a reasonable minimum length of uninterrupted
street segment (preferably 1,200 feet or more) to be considered
for installation of humps. This requirement will be evaluated by
the City Traffic Engineer on an individual basis.
4. The number of humps, their locations, and spacing between
them will be determined by the City Traffic Engineer. The
City's Fire and Police Departments will be consulted for these
determinations.
5. The installation of humps may shift or divert some traffic onto
parallel residential routes. Any insignificant shift or diversion of
traffic should be accepted as a by-product of these
devices Page 16 FileName:
RNlMProgram Disk #19\
without need for further mitigation. All significant re-
routings,as determined by the City Traffic Engineer, will be mitigated
to the fullest possible extent on individual
basis.Page 17 File Name: RN1M
Program Disk #19\
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WARNING ""~
EX. Ca.G
SIGN PLAN
VIEW N:r.S.
NOTES,
I. SPEED HUMPS SHALL BE LOCATED BY THE ENGINEER, AND/
OR AS SHOWN ON PLAN.
2. SPEED HUMP
SHALL BE CONSTRUCTED
TO
A HEIGHT OF 0.292' (3.5")PLUS OR MINUS 0.031' (0.
375") AT
THE
MIDPOINT. THE CORRESPONDING SHAPE SHAll: FOLLOW A CIRCULAR ARC (SEE SECTION A-A).3.
PLACEMENT OF ASPHALT TO BE IN ACCORDANCE WITH STANDARD SPECIFICATIONS FOR PUBLIC
WORKS CONSTRUCTION, LATEST EDITION INCLUDING SUPPLEMENTS.4. ASPHALT SHALL
BE TYPE =-C3-AR4000 0/2") OR AS DIRECTED BY THE
ENGINEER WITH 6 % ASPHALT BINDER.SINGLE CURVATURE SPEED
HUMP EXHIBIT 2 W37 MODIFiEr I 5 W 6 (15)MPH t-11/
2"UNISTRUT POSTWm I 3/
4 BASE ADVANCE WARNING
SIGN
26'
PICAl
120WHITE~ AL-
13' 12' 11'\ 10' 9' 6' T 6' '5
r~ ~~ ~ ~ ~ ~-
CENTER
OF TRAVEL LANE H ~ ~
J
AOPTIONAL 100'
DESIRABLE--
4~I~
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1 5'5c,
Section B-
B f:::::2'
MAX1120-,I (WIDTH VARIES)
TAPER.
CURBFAC~
CURB DETAIL
CITY OF PORTLAND STANDARD
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CITY OF
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MIX
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COAT SHOULDER
DETAIL FOR STREETS WITHOUT
CURBS FLAT
TOP SPEED HUMP"EXHIBIT
3
Traffic Circles
Traffic circles are raised (or unraised, temporary trial installation) islands
placed in the center of an intersection. Their primary purpose is to slow high-
speed traffic. They can be installed at either controlled or uncontrolled
intersections. Traffic circles are most effective when constructed in series.
The raised median forming the circle can be either landscaped or hardscaped.
Plan views of typical traffic circles are presented in Exhibits 4 and 5.
ADVANTAGES DISADVANTAGES
Effectively reduce speeds Requires some parking removaL
Improve safety conditions (i.e.,Can potentially increase bicycle/
reducing left-turn accidents)auto accidents due to
narrower Visually attractive (iflandscaped
lanes properly)May restrict emergency
vehicle access, if cars park illegally
near the
circle.The traffic circles can be designed and constructed according to
dimensions specified in Exhibits 6 and
7.Page 18 FileName:
RNIMProgram Disk # 19\
The potential location and number of traffic circles will be determined by the
City Traffic Engineer in consultation with the area residents and City's Fire and
Police Departments. Temporary circles using flexible posts may be tried on an
interim trial basis before constructing the permanent islands.
COST: Depending on the size and treatment of the raised islands, a typical
traffic circle at a residential street intersection can cost between $8,000
hardscaped) and $12,000 (landscaped).
Page 19 FileName: RN1MProgram
Disk # 19\Thenp
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EXHIBIT
4
Traffic Circles
1, ..
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Traffic Circle - Full Circle Traffic
Circle - Partial Circle EXHIBIT 5
Vlries 5.5 ~
INTERSECTION DIAGRAM
Legend:
A Street Width
B arb RetlITl Radius
C Off - Set Distance D
Cirde Diameter E
Opening Width OPTIMUM
OIf-
Set
DistQr\NO
5.5 max
5.0'
4.5
40'
3.5 or 4ess
CRITERIA
Opening
WidtL
16'min
17't
18'~
19'1
2d
EXHIB!T 6
A B C 0 E
STREET CURS RETURN a=F-SET CIRaE
OPENING WIDTH RADIUS DISTANCE DIAMETER
WIDTH 20' '" <'5 ~cOOStrucl
Curbs 5' 5.5 9' '
6'.le' 5.0' la'
17' .20' 4.5' 1\' la' -
25' 4.0' 12' 19'.
24' '" <12' Reconstruct Cu-
bs 12' 5.5' 13'
16'15' 5.0' 14' 17'-
20' 4.5' 15' 1a'.
25' 3.5' 17' - 2C1-1
Reconstruct DIMENSION
CHART 25
12'
15'
le'
20'
5.
5'5.
0'4.
5'4.
5'3 '
5.
5'5.
0'5.
0'4.
5'4.
0'30'
0'12'
5'
e'
20'
32'
0'12'
15'
le'
20'
5.
5 5.
0'4.
5'4.
0'4.
0 36'
10' 5.0'12'
5.0'15'
4.5'4.
0.20'
3.5'25'
1.5'0'
5.0'12'
4.5'5'
4.0'lS'
3.5'20'
3.0'25'
1.0'Substandard
Width Streets EXHIBIT
7 4d
Existing
Curbs
14'
15'
16'
16~
1 '
19' .
20'
20'
21'
22'
21'
22'
23'
24'
24'
26'
26'
27
28'
29'
33'
30"
31'
32'
33'
34'
38'
6.
1/-
la'-le.
16'.1/-
17'.
1a'.
19'.
16 .17' -
18' -
19' -
19.
17 -
17'.18'.
19'.2d-
2CJ 17'.
18'.
19'-2d-
2d
20'
NARROWINGS
Narrowings of street cross-sections (usually at intersection approaches,
but could be at mid-block locations as well) is reducing the roadway
width by widening sidewalks and/or parkways. Narrowings reduce traffic
speeds, but they also enhance pedestrian safety by making crossing points more
visible and by reducing crossing distance across the roadway. Plan views
of typical narrowings are presented in Exhibits 8 and 9. Typical dimensions
for a narrowing at an intersection are shown on
Exhibit 10.
ADVANTAGES DISADVANTAGES Slightly reduces speeds. . Creates
additional potential Improves pedestrian safety.
collision obstacle.Aesthetically improves the street . Usually results in loss
of some if done properly).
on-street parking.Provides opportunity for gateway . May require
re-working of street treatment to define neighborhoods. drainage
which could be very Allows signs to
be placed closer costly.to driver'
s line of vision.Probably the greatest attribute of narrowings (
also known as "curb-extensions") are their psychological effect when
used properly at several locations throughout the neighborhood. Key factors
to consider in their Page 20
File Name: RNlM
placement are loss of parking, street drainage, emergency vehicle operation,
and impact on City services such as street sweeping and waste collection.
Narrowings must be designed individually. Their locations and configurations
shall to be approved by the City Traffic Engineer.
COST: Depending on the drainage needs of the intersection, cost of
narrowmgs can vary. If no major re-work of drainage is needed, they can
be done for about $6,000 per
location.Page2!File Name: RN1M
Program Disk #!9\
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NOTE: TREATMENT MAY VAAY
DEPENDING ON DRAINAGE
DESIGN
Typical Intersection Narrowing Design
EXHIBIT 10
Diverters
Diverters are physical barriers across the street.They could be partial
diverters (barrier across half of the street) or full diverters (barrier across full
width of the street). Diverters are mostly used at intersections and can be
designed in a variety of configurations depending on the project needs. Some
examples are diagonal diverter and forced-turn channelization. The
primary use of diverters is to shift and re-route vehicles in the cases of
excessive "cut-through" traffic. Examples of diverters are shown on Exhibits II
through 14.
ADVANTAGES DISADVANTAGES Self-enforcing. . Usually
shifts the problem Completely
eliminates "cut-through"
elsewhere.traffic.Separates communities.
May adversely impact emergency response
time and City services.Diverters are very restrictive forms of traffic
management and have significant impacts on area wide traffic patterns. Their
placement should only be considered after a comprehensive traffic study
and through active community
participation and public hearings.Under certain conditions, to be determined by the
City Traffic Engineer, the function of diverters may be accomplished through
the use of turn-restriction signs only. However, such regulatory signs
are usually effective only when Page
22 File Name:
combined with extensive enforcement activity and are not considered self-
enforcing in most cases.
COST: Varies depending on the project and the type of diverters.
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EXHIBIT
11
Semi-Diverters (One-Way Entrance
or
Exit)
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traaoe or Eldt
0IlIy EXHIBIT12
One-Way
Streets I
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T /~/Converging One-
Way Street Meeting
One-Way Streets
Converging One-Way Street
Meeting Two-
Way
Cross
Street i
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Channelization and Median Islands
I-'
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Star
RequireS All Right Turns
Diagonal Island
Elliminates Throughs
and Some Lefts
i..~ . , .
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Islands
Right
Turns
from Side Street Diagonal Island
Three Quarter
Diverter r~. . .Island
on '
lbrougb
Stnet at T.
lntenection Partial T.I.
nd IUcht Tarn. from
Side Stnet EXHIBIT 14
OFFSET-
NARROWINGS Offset-Narrowings are artificial blockages on opposite sides of the streets
at an off-set configuration to create an S-curvature on
a naturally straight street.The purpose of the offset-narrowing is to
reduce traffic speed and produce caution in the driver. Typical layouts
for offset-
narrowings are
shown on Exhibit 15.ADVANTAGES DISADVANTAGES Reduces traffic
speed.Usually results in significant loss Aesthetically
improves the street.of
on-street parking.Expensive
to implement as usually
requires
extensive street re-work and
even utilities relocation.
Not effective on streets
with substantial horizontal
curvature or where crest-vertical curves limit sight distance.Offset-narrowings
may only be placed through a detailed re-design of the
street. This can only be
done subsequent to extensive community participation
and budgeting a specific
project.COST: Varies
OFFSET -NARROWINGS
Offset-Narrowings - Mid-
Block r\:/:>\j 1>
1
u.___..-.
Offset
Narrowings -
Using Throating at Intersections EXHIBIT 15
Neighborhood Traffic Watch
This program requires extensive community involvement and public education.
Radar units are purchased and provided by the City. Volunteer residents are
trained on the use of the radar unit and the appropriate field operation and
precautions. The residents will record the license plates of habitual speeders in
the area and report them to the City. The City's Police Department forwards a
courtesy letter to the registered owner of the vehicle informing him/her of the
observed violations with a reminder to observe the speed laws.
In order to minimize amount of training and possible conflicts between "over
zealous" residents and speeding drivers, the previously established cadre of
volunteers" in the Police Dept. may be used for implementation of this
program. These individuals have already received some training, and as they
do not live in the "Study Area" they will not over-extend their
limited monitoring functions to enforcement
activities.ADVANTAGES
DISADVANTAGES Involves the community in the Requires extensive
residents solution of problem.
involvement.Potentially reduces speeds and on Requires extensive and
ongoing occasions divert traffic resulting public education to
minimize in lower volumes.adverse legal
implications.Page2S File Name: RN1M
Pmgnun Disk #19\
Could be used in many neighborhood . It usually takes a few months to
in the City at a reasonable cost.observe the effectiveness of
the program.
These programs, if implemented properly, could be effective. Most of the
violators who receive the courtesy letters from the Police Department either
change their travel routes or reduce their speeds on the study street.
SCAQMD has a similar program for identifying potential mobile sources of
pollution.
COST: Radar units are about $2,000 per unit. To have an effective program,
the City of Orange will need at least 5 units. The staff time estimated to
administer this program (inclusive of Police Department) is about $55,000 per
year (this cost may be lower in the future years after the program is more
developed).
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Video/Photo Enforcement
These units monitor traffic speeds automatically and take a picture of the
license plate of vehicles that are speeding. The pictures are used to Issue
citations. The units are mobile and can be used at different locations
throughout the City.
ADVANTAGES DISADVANTAGES
Speeds are reduced when units Results usually diminish once
are present.units are moved.
May have longer term effects, if Will take weeks (or months) for
properly combined with a public the violators to receive the
education campaign.Citations. This will be fiustrating
Can be used at different locations.to residents as the effects will not
be visible for a long time.
Can only be placed at locations
with a good visibility (to
minimize the collision potential).
California State laws currently allow use of such devices, yet some of the
citations have been challenged in the Courts. The Courts in northern California
have not looked at these units favorably and the whole issue is being
considered by the District 9 Court of Appeals. These units will only be
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effective, if several of them are used strategically on a rotation program
throughout the city combined with a well publicized public education program.
COST: Private firms provide at no cost to the City. They share ticket
revenues.
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Speed Wagon/Radar Trailers
These are portable radar units that are capable of measuring and displaying
vehicle speeds. They have a very limited effect on reducing speeds when the
units are present. This limited effect completely disappears once the unit is
relocated to another location. The City currently has one such unit that is
being used at different locations depending on needs.
ADVANTAGES DISADVANTAGES
Units are mobile and can be used at . Effects usually disappear once the
different locations.unit is relocated.
Speeds are usually reduced when May only be used at locations
units are present.with good visibility (to minimize
Units may have long term effects collision potential).
psychologically) by raising driver's
consciousness about speeding.
COST: About $12,000 per unit plus staff time to move the units to different
sites.
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Driver Education
At locations where the "cut-through" traffic or habitual speeders are
an identifiable group of individuals; i.e., schools in the area or large
office complexes, driver education program can be effective in changing
driver behavior and/or travel patterns. City staff (Traffic Engineering Division
and Police Department) meet in group format with the target audience and
attempt to resolve the problems without any measures on the
street.ADVANTAGES
DISADVANTAGES Solves the problem without any May only be used at
locations changes to the streets.where violators are
an Involves the violators in the identifiable (and
accessible)group ofpeople.solution of the
problems.Requires extensive and
well-coordinated staff effort on
a continuous
basis.COST:
Varies.Page 30 FileName:
RNIMProgram Disk #19\
Selective (Focused) Police
Enforcement
Focused and visible enforcement of speed laws has proven to be the most
effective method for reducing traffic speeds. However, this technique can not,
unfortunately, be sustained on a long term basis due to the limited availability
oflaw enforcement resources and other competing priorities. Nevertheless, for
certain types of problems demanding quick action, an increased focused
enforcement may yield desirable outcome, albeit temporarily.
ADVANTAGES DISADVANTAGES
May be deployed quickly with no Can not be sustained for long
special procedure needed.term projects.
Usually is very effective in Effects usually diminish once
reducing speeds (temporarily).the enforcement level is
Penalizes the violators.decreased.
Diverts limited law enforcement
resources to non-violent
crimes.COST:
Varies.Page 31 File Name: RN1M
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Slow Points (Mid-Block
or
Intersection)Slow points are small islands in the middle of the street narrowing travel
lanes.They can be installed either at intersections or mid-block. Slow points
are used to enhance pedestrian crossing points and depending on their
location and configuration may also result in small to moderate reductions in
traffic speed.Plan views of typical slow points are presented on
Exhibit 16.
ADVANTAGES DISADVANTAGES May reduce traffic speed.Requires removal
of some Make pedestrian crossing points
on-street
parking.more visible.Prevent
vehicles passing other vehicles
that are
turning at intersections).The location and configuration of Slow Points should be
determined by the City Traffic Engineer
on individual basis.COST: Varies. Typical installation will cost
about $2,500.Page 32 File
Name: RNIM Program
I~C':^~
SLOW POINT
INTERSECTION]
SLOW POINT
MID-
BLOCK]EXHIBIT