HomeMy WebLinkAboutTIC 2019-08-20 Item 2C - Update - Neighborhood Traffic Calming ProgramAllan Ekberg, Mayor
Public l,'Vnrks Department Henry Hash, Director
INFORMATIONAL MEMORANDUM
TO: Transportation and Infrastructure Committee
FROM: Henry Hash, Public Works Director 1, 4/
BY: Cyndy Knighton, Senior Program Manager
Scott Bates, Traffic Engineering Project Manager
CC: Mayor Ekberg
DATE: August 16, 2019
SUBJECT: Neighborhood Traffic Calming Program
Project No. 80910301
2019 Progress Report
ISSUE
Provide a summary of progress to date for the Neighborhood Traffic Calming Program (NTCP).
BACKGROUND
The NTCP was adopted by Council Resolution (No.1955) at the end of 2018 to address neighborhood
concerns with traffic safety. The Council also wanted to ensure that traffic calming safety decisions are
based on technical engineering and applied in a uniform and consistent manner. The 2019-2020 budget
provides annual funding to implement traffic calming strategies on residential streets and other safety
improvements throughout Tukwila. Although some work was accomplished in 2018, this program is taking
off and much more has been accomplished in 2019.
DISCUSSION
Staff has collected requests for traffic calming treatments and other improvements in residential areas
for many years. Requests for calming treatments and other safety improvements come into staff via a
variety of ways:
• Enrollment requests from the City's website • Face-to-face conversations
• See-Click-Fix/Tukwila Works • Other Departments, especially Police
• Email inquiries • Historical knowledge
• Phone calls • Elected officials
The NTCP is a welcoming program for our community and has already produced positive results to
improve safety. When the Council adopted the NTCP, staff had a list of approximately 22 requests.
Currently, there are more than 40 individual requests for improvements, and it is not uncommon for new
requests to come in weekly.
The NTCP has two levels of calming treatment types to use. Level I treatments are considered passive
traffic control and are generally less restrictive than Level II treatments. Level II treatments focus on
physical devices which are more costly and restrictive. Due to an increased number of requests today,
staff is not strictly following the steps of the NTCP.
In order to begin addressing requests quickly, staff has been installing new permanent speed feedback
signs and LED enhanced signs which fall under the Level 1 category of improvements in the NTCP.
Additionally, staff has installed many new parking restriction signs at the request of both residents and
the Police Department to aid in enforcing parking violators and improve safety. These also fall under the
Level 1 category. 35
W:1PW EngIPROJECTSIA- RW & RS Projects\Traffic Calming\Tukwila Traffic Calming Program\NTCP 2099 Progress report.docx
Traffic Calming Info Memo
Page 2
The attached map shows the locations where traffic calming treatments have been implemented to date.
Requests have come in for new crosswalks in the vicinity of schools, parks and other high pedestrian
generation areas. Crosswalks require engineering study to ensure that they are safely sited, and the City
is legally protected. For example, one location, S 144th Street at 37th Avenue S, staff is recommending
installation of a Rectangular Rapid Flashing Beacon (RRFB) on the west leg of the intersection's existing
crosswalk because of the close proximity to high density residential and the Cascade View Park. A new
marked crosswalk is considered a Level 1 treatment, but the RRFB is a Level 2.
KPG has recently been contracted to assist staff with the engineering for crosswalk siting studies,
development of general RRFB plans, and other needs that may come up on an on -call basis. It is likely
that additional consultants would also be retained for on -call engineering services to support the NTCP
program.
The NTCP is a great program that brings staff closer to the community which helps staff understand their
needs and issues. In order to keep up with the requests in a timely, professional and safe manner, a
more organized, programmatic traffic calming program is needed. To reach this point, dedicated staff are
required to provide accurate ranking and studies as well as to install and maintain the additional
infrastructure. Additional staffing will move this new program into one that complies fully with the adopted
NTCP.
RECOM M ENDATION
Information only. Committee is being asked to have the Neighborhood Traffic Calming Program update
presented to full Council at the August 26, 2019 Committee of the Whole.
ATTACHMENTS
• Page 8, 2019 CIP
• Resolution No. 1955 — Neighborhood Traffic Calming Program
• Map of 2019 NTCP improvements
• Matrix of Description of Traffic Calming Methods
• Matrix of Traffic Calming Methods — General Overview
36
CITY OF TUKWILA CAPITAL PROJECT SUMMARY
2019 to 2024
PROJECT: Traffic Calming/Residential Safety Improvements Project No. 90210301
Programmatic approach to addressing neighborhood traffic concerns through a variety of methods.
DESCRIPTION: Residential street improvements with sidewalks, safety improvements, and bike facilities.
JUSTIFICATION: Neighborhood revitalization by improving residential streets.
STATUS: Future candidates are listed in the citywide comprehensive update and safety -based prioritization of
residential street improvements, sidewalks, and bike lanes.
MAINT. IMPACT: Varies, depends on treatment(s) used.
COMMENT: Residential improvements have included 42nd Ave S, 53rd Ave S. Speed cushions installed at S 160th St.
FINANCIAL Through Estimated
(in $000's)
2017 2018 2019
2020
2021
2022
2023
2024
BEYOND TOTAL
EXPENSES
Design
9
80
80
80
80
80
80
80
569
Land (RNV)
0
Const. Mgmt.
0
Construction
38
320
320
320
320
320
320
320
2,278
TOTAL EXPENSES
47
0
400
400
400
400
400
400
400
2,847
FUND SOURCES
Awarded Grant
0
Proposed Grant
0
Mitigation Actual
0
Mitigation Expected
0
City Oper. Revenue
47
0
400
400
400
400
400
400
400
2,847
TOTAL SOURCES
47
0
400
400
400
400
400
400
400
2,847
2019 - 2024 Capital Improvement Program
8
37
Special Meeting thereof this 10174 day of
ATTEST/AUTHENTICATED:
(,) ---
Chrigty y, MMC, City
APPROVED AS TO FORM BY:
Rachel .-Turpin, City Attorney
Washington
Resolution No.
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF
TUKWILA, WASHINGTON, ADOPTING THE "CITY OF TUKWILA
NEIGHBORHOOD TRAFFIC CALMING PROGRAM."
WHEREAS, one of the top concerns of Tukwila community members is speeding and other
dangers associated with motor vehicles; and
WHEREAS, the City of Tukwila desires to reduce the negative effects of motor vehicle use,
alter driver behavior, and improve conditions for non -motorized street users; and
WHEREAS, the adopted Tukwila Comprehensive Plan recommends implementation of a
neighborhood traffic calming program in both the Transportation Element and the Residential
Neighborhoods Element; and
WHEREAS, the City Council desires to document a transparent, predictable and equitable
process for implementing effective traffic calming measures in neighborhoods throughout the City;
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON,
HEREBY RESOLVES AS FOLLOWS:
The "City of Tukwila Neighborhood Traffic Calming Program," as evidenced in Exhibit A, is
adopted.
PASSED BY THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON, at a
./e° , 2018.
o
Verna SeI,Cou'fliI President
Filed with the City Clerk:
Passed by the City Council: ) Resolution Number:
Number: i C
Attachment: Exhibit A — City of Tukwila Neighborhood Traffic Calming Program
W:\Word Processing \Neighborhood Traffic Calming Program 11-30-18
LH:bjs
Page 1 of 138
ulnuu
CITY OF TUKWILA
PUBLIC WORKS DEPARTMENT
NEIGHBORHOOD TRAFFIC
CALMING PROGRAM
Adopted December 10, 2018
By Resolution No. 1955
39
Table of Contents
OBJECTIVES 1
PROCESS STEPS 1
INITIATING A REQUEST 1
PRELIMINARY EVALUATION 2
SOLUTION ALTERNATIVES 2
No Action 3
Level I 3
Level 11 3
PROCESS FOR QUALIFYING FOR LEVEL II TREATMENTS 3
PLAN DEVELOPMENT 4
PROJECT FUNDING 4
PROJECT DESIGN AND CONSTRUCTION 5
EVALUATION 5
RE -ENROLLMENT 5
APPENDICES
APPENDIX A: DEFINITIONS OF TYPES OF STREETS
APPENDIX B: PRIORITY RANKING WORKSHEET
40
Introduction
Traffic conditions on residential streets greatly affect neighborhood livability. Speeding and
unnecessary through -traffic in neighborhoods create safety hazards on residential streets. The City
of Tukwila Public Works Department has developed a Neighborhood Traffic Calming Program
(NTCP) to guide City staff and inform residents about the procedures for implementing traffic
calming on residential streets and collector streets.
The NTCP is designed for local residential streets and collector arterials only. The NTCP does
not apply to local or arterial streets in commercial areas or to streets classified as principal or minor
arterials.
As defined by the Institute of Transportation Engineers (ITE), traffic calming is the application of
measures which can be taken which reduces the negative effects of motor vehicle use, alters driver
behavior and improves conditions for non -motorized street users. The City's NTCP outlines a
process for staff and residents to carry out a traffic calming program. It provides a way to
objectively prioritize traffic calming requests. These procedures incorporate prioritization,
planning, evaluation, implementation, and maintenance of the traffic -calming devices in
residential areas. It also combines the four E's — Education, Engineering, Enforcement and
Emergency Services.
Obiectives
The primary goal of the City' s NTCP is to improve the livability of the local streets and residential
collectors. The City has identified the following objectives:
• Provide alternative solutions to reduce vehicular speeds and accidents on residential streets.
• Endorse safe and pleasant conditions for motorists, bicyclists, pedestrians, and residents of
neighborhood streets.
• Provide a means for a collaborative working relationship between City staff and
neighborhood residents in development of traffic calming measures.
• Discourage use of residential streets for cut -through vehicular traffic.
Process Steps
Initiating a Request
Request for traffic calming assistance can come from a resident' s association or from concerned
individuals. Requests can be made in writing by clearly stating the problem and location,
accompanied with completed application which is provided by the City. The request can be made
by either mailing or emailing the request to the Public Works Department. The request must
include a contact name, address, phone number and email.
41
Staff will then acknowledge the completed application in writing to the resident' s association or
to the contact person listed in the application. An application fee could be implemented in the
future to offset some of the costs involved.
Preliminary Evaluation
Each street in the community is a part of the larger roadway network that connects residents to
each other, work, schools, goods, services and the countless destinations to which drivers and
pedestrians travel daily. Common issues within neighborhoods include speeding, traffic volumes,
and the utilization of neighborhood streets as a cut -through route, among others. In order to ensure
that traffic calming concerns are addressed in an equitable manner, staff must assess the situation
by reviewing the request and determining if the area qualifies for treatment using set criteria. The
primary purpose of a preliminary evaluation is to determine whether the speeding or accident
situation is significant enough to warrant further study. At this stage, staff collects data to analyze
it to determine whether:
• The roadway is eligible for traffic calming treatment.
o Only residential streets classified as collector arterial or local access are eligible.
• City recorded data supports the problem identified in the application.
o Speeding: Traffic counts are taken to determine if 15% of the motorists travel at 5
mph or more above the posted speed limit. This is also referred to as the 85th
percentile speed being at or above 5 mph over the speed limit.
o Volume: Traffic counts also collect the number of daily vehicles on a street. This
information is used to determine the best type of solution and is used to rank project
priorities.
o Traffic Accidents: The number of accidents for over a three-year period is collected
and studied.
The Public Works Director has the discretion to move an application forward or to address any
safety issues discovered outside of the NTCP process.
If the analysis confirms that a traffic problem exists based upon the above criteria, the Public
Works Department will conduct a traffic calming study as explained in the following sections and
staff calculates the priority score for the street segment using the Priority Worksheet in Appendix
C.
A written response back to the contact person with the findings of the preliminary evaluation is
generally provided within 60 calendar days of the request.
Solution Alternatives
The solution alternatives are defined into three levels.
42
No Action
After data collection and analysis is complete, any location not meeting the above criteria will be
determined to not be eligible for any NTCP assistance. Staff will inform the applicant in writing
that their request does not meet the City criteria for action and the request will be closed.
Level I
The first level improvement for traffic calming that should be considered are passive traffic control
treatments, known as Level I. Level I improvements are less restrictive measures, and do not
require a vote of the affected residents. The improvements used in Level I include: trimming
bushes to allow better sight distance; pavement markings and striping; increased police
enforcement; traffic speed display signs; neighborhood awareness campaigns; and education. This
reduces the need for installing physical devices on every local street.
If a marked crosswalk is recommended for installation where ADA-compliant ramps do not
currently exist, the improvement will be automatically treated as a Level II solution.
Level If
Level II improvements should be considered only after Level I treatments have been in place for
a minimum of 6 months and data collection and analysis indicate the problem(s) has not been
resolved, or as determined by the Public Works Director. Level II improvements focus on physical
devices such as speed cushions, traffic circles, and chicanes to calm traffic. These solution
alternatives are much costlier than Level I and are generally permanent. Therefore, a more detailed
evaluation is required and approval by key departments and impacted area residents is required
before the implementation. The detailed evaluation includes as follows:
• The speed, volume and accident history collected during the preliminary evaluation.
• Collect new traffic speed and volume data and accident history for the past three
consecutive years.
• Other factors such as proximity to schools, parks and other pedestrian generators, lack of
sidewalks, accessibility, presence of bicycle facilities, and other roadway characteristics.
• Identify users of the affected streets.
• Identify traffic and major pedestrian generators, such as schools, parks and shopping
centers.
• Analyze street use with respect to street classification.
• Document any other relative factors.
Process for Qualifying for Level II Treatments
If the traffic problem(s) has not resolved with Level I treatments, an impact area is established by
staff after identifying users of the affected street(s), identifying major traffic generators such as
schools and parks, analyzing the actual street use with respect to roadway classification, and any
other relative factors. The impact area includes the location requesting treatment as well as other
streets in the immediate area that could be impacted by Level II treatment installation.
43
Plan Development
Once an area has been selected for a traffic -calming project, steps need to be taken to determine
solutions. The applications are prioritized based on the scores. The highest-ranking applications
will be given priority in moving forward into Plan Development, as funding allows.
Since Level I solutions are simpler in scope, the solution formulation process can usually be
handled by staff. Public meetings are not usually required, although some type of public
communication is beneficial and recommended.
Level II improvements require a more comprehensive plan development due to the higher cost and
impact of the actions taken. A public meeting with all affected residents may be held, as
determined by the Public Works Director. The initial public meeting will:
• Discuss the steps to develop a traffic -calming plan.
• Gather additional information regarding traffic problems and related neighborhood needs.
A ballot may be provided to each resident, either in person or via the postal service, to vote to
indicate support of the NTCP plan. The implementation plan must receive at least 2/3 approval of
all residents on the impacted street in order to proceed. In addition to the community support, the
approval of the following public officials is required:
• City Police and Fire Departments
• City Council
Once the necessary level of support is documented, projects may be funded and constructed
according to their prioritization and as available staffing and budget permits.
In cases where a Level II request does not receive sufficient support, the project is dropped from
the list and the next highest ranked project can go through the same process. Residents in an area
where a project has been dropped are able to resubmit their request for the following program year.
Project Funding
The number of traffic -calming projects undertaken each year depends on the City' s budget and
staffing availability. The City Council's Transportation & Infrastructure (or successor) Committee
will be kept apprised on projects both proposed and selected on a regular basis, and the City
Council will be notified of the NTCP's progress and expenditures at least every six months.
In some cases, landscaping, maintenance and necessary easement dedication may be the
responsibility of the residents or the homeowner' s association. If this is the case, an agreement
must be signed between the City and residents before the project is implemented.
44
Project Design and Construction
Once traffic -calming treatments have been determined, the City' s staff or a consultant develops
the detailed plan, based on the study and the residents' input. The traffic calming device will be
installed.
In some situations, a test installation may be warranted to assure that the device is both effective
and truly desired by the community. In this case, within three to twelve months after installation,
staff evaluates how well the test installation performed in terms of the defined problems.
Evaluation
An evaluation shall be conducted between six months to one year after the implementation of any
permanent traffic calming devices. Speed, volume and collision data is collected and compared
with the data collected before the installation of the traffic -calming device. The data collection
should be done at approximately the same time of year as the original data collection.
Re -enrollment
If additional traffic calming treatments become necessary in the future due to changes in traffic
patterns unrelated to the NTCP treatments, requests can be made for a new enrollment 12 months
or more after the last evaluation period has been completed. The submission will be treated as a
new request beginning with preliminary evaluation and will follow the NTCP process. Any future
traffic calming treatments will be scored and ranked along with all other active requests and are
subject to funding and staffing availability.
45
Appendices
46
Appendix A: Definitions of types of streets
The City' s Transportation Element of the Comprehensive Plan defines the street functional
classifications. For the sake of this program, only residential local streets and collector arterials
are eligible for NTCP treatments. Streets in commercial areas or which are classified as principal
or minor arterials are not eligible for treatments under this program. Traffic calming on principal
and minor arterials is very different than on residential streets, requiring substantial design,
permitting, environmental approval, and budget in order to construct. These calming projects are
developed into standalone capital improvement projects.
Local streets (typical speed limit 25 mph) serve local circulation needs for motor vehicles,
bicycles, and pedestrian traffic and provide access to residences and some businesses. Local
streets are not intended to carry significant volumes of through traffic. Sixty to 80 percent of
the roadway network is considered local streets.
Collector arterials (typical speed limit 30-35 mph) are typically streets that provide access
between local service streets or from local streets to thorough -fares. Collectors often carry
some through traffic. Collectors in residential areas are eligible for NTCP treatments whereas
collectors in commercial areas are not. Five to 10 percent of the roadway network is classified
as collector arterials.
Minor arterials (typical speed limit 30-40 mph) are streets which are typically wider and
may have more lanes than collectors which connect the smaller arterial streets to destinations
or to the regional roadway network. Minor arterials carry a large percentage of through traffic
as well as traffic from the local area. Ten to 20 percent of the streets in network are minor
arterials.
Principal arterials (typical speed limit 35-50 mph) are major streets and highways that
provide regional connections between major destinations. Speeds are higher, access and
traffic control favors providing fast and smooth movement on the arterial over the lower
classified streets. Five to 10 percent of a roadway network is classified as principal arterials.
47
1101lcr 131vd
Roadway Classification
afiatifitf Freeway
Principal
inaanna Minor
Collector
City of Tukwila
oio Potential Annexation Area
NOT TO SCALE
ROADWAY CLASSIFICATION
Appendix B: Priority Ranking Worksheet
Location:
Date:
Staff Name:
Category
Data
Scare
Accidents:
Five points for each recorded accident over the past three years. Three
additional points will be added for each accident with a recorded injury.
Volume:
Average weekday traffic volume divided by 100, rounded up to the
nearest whole number. Maximum of 7 points possible.
Speed:
Five points for every mph greater than 5mph above the posted speed or
(85th percentile speed - posted speed limit - 5) x 5 points.
Sidewalks:
Five points if there is not a continuous sidewalk on one side of
residential streets or both sides of collectors.
Pedestrian Generators:
Five points for every K-12 school on and 2 points for school property
within 500 ft of the subject street. Three points for other major
pedestrian generator on the subject street. Major pedestrian generators
may include parks, community centers, senior housing, or other uses
with significant pedestrian traffic.
Total Points:
49
133
S 86 pi
N 0
0
3
4
S 128 St
MJ
Pending
LED Curve Signs
Speed Cushion
Radar feedback
LED Stop Sign
RRFB Crossing
School Zone Flasher
Map Legend
OH
City Facility
City Bathroom
• Fire Station
0
0
1111111
Police Facility
School
Trail
Street
Tukwila Park
Waterbody
City Limits
0
6
6
0
S 112 St
m
ecord
enter S 1 ,2 St
S 142 St
CO S146 St 0
S 152 St
CO S158 St
S 164 St
City of Tukwila
NTCP 2019 Installations
3h. alter
S
S 160 St
S 161
< S 162 St
01
6
0
0
0
0
5
11
0
0
0
ior
6
0
/ Foster Golf
Clubhouse
Parks & Golf.. \
Maintenance ,)
rue twig
Shops
143St
S143 P1
Tukwila Lib
FS 52
Resource
Center
Strander Blvd
Corporate Dr S
Mlnkler Blvd
Upland Dr
Midland Dr a
0
a
Trlland Dr Q
S 180 St
NOT TO SCALE
0
M;nN
Sho,
Saxon Dr
O
0
0
0
0
0
6
0
O
0
0
6
11
0
0
0
0
6
s
0
0
0
0
0
s
0
11
0
0
0
0
0
0
0
0
51
0
0
0
GIS
Tukwila
DU
Method
Speed Watch
Program
Descriptions of Traffic Calming Methods
Description
• Residents check out radar gun and gather speed data in spot locations
• Data gathered is used to validate other speed data
• Residents learn what certain speeds "feel like" when standing on or near the roadway
Cost
$
Radar Speed
Signs
• Solar powered signs can be installed permanently or rotated
• Can be used in conjunction with a target enforcement emphasis -- traffic officers can be found further down the road to provide
police backup of the legal speed limit
$-$$
Targeted
Enforcement
• A progressively stricter enforcement schedule with low thresholds for citations
• Traffic officers work a select location over a period of time, graduating from marked police cars to ultimately unmarked cars
$$-$$$
Striping
• Installing center, walkway, and edge line markings to narrow or modify the travel lanes
• Unique striping in individual cases can be used successfully
«iint`
• Striping can include: IIII v% Ay
yellow center skip strip Edge Lille
white edge lines
wording on pavement
ped walkways and bike lanes c,
marked crosswalks
• Applications are determined in each instance and can be modified to fit
individual needs
• Paint cannot be applied year round -- weather dependent installation
• Striping an unstriped roadway gives the appearance of a narrowed road
and assigns where vehicle and pedestrian areas are located
nir B
es "
A° ,'
,,;,
N WA
$ n t o&ri
don
$-$$
Vegetation
Trimming
• City crews will trim vegetation in public right-of-way to improve sight distance at intersections, sign visibility, or general safety
• Vegetation that is in private property can only be trimmed by city crews if impeding sight distance or creating a safety hazard
• Property owners are always first encouraged to trim their private plantings
$
Improved Signage
• Signs already in place may be improved by installing larger signs, or LED enhanced signs
• New signs may be installed as warranted
• Existing signs may be relocated to provide maximum impact
$-$$
Traffic Safety
Campaign
• This effort not currently defined by Tukwila
• Could include development of traffic safety brochures or flyers
• Could be developed to incorporate local high school education
• Could be jointly implemented using the PD Sprint program and targeted enforcement
$$-$$$
Multi -way Stop
• All -way, or multi -way stops are installed at intersections where traffic flows are generally fairly equal on all legs
• Engineering warrants must be met before installation can occur
$-$$
Pedestrian Safety
• Improvements can include:
$$-$$$
Measures
Sidewalk or walkway installation 41
Crosswalk installation ,,h1
P.1.4
paint
textured pavement treatment
Pedestrian signals (RRFB, HAWK)
lj
m"'"" °
Pedestrian scale lighting improvements
Pathways
Raised crosswalks
tt
"
_,, _ .„_
w
<w
Mid block crossings
:
fiss
`�
with or without
•; < ' -�.►n
refuge area
,'`«
;
1
y
.01111
a
II;
��i't(
Gateway/
Entrance
• Sometimes called planter islands, these are typically
• On wide streets, curb
long
and
narrow islands placed in the middle of roads
at
intersections
$$-$$$
Treatment
extensions may be used on
both sides of the roadway
while still maintaining 2
��
ti
lanes of roadway width
13
i
• In some cases, pedestrian
w
i
amenities such as raised,,
crosswalks, decorative
or simple
x
pavement,
u
painted crosswalks are also
included as part of the !��,"
s''
z>
q,.
treatment
• May also include additional
street lighting for the
intersection and decorative entrance signs
A
`"
51
Descriptions of Traffic Calming Methods
Method
Description
Cost
Traffic Circle
• Round islands installed at intersections to force traffic to circle around the
island, thus disrupting the flow of traffic
• Less expensive traffic circles can be painted on the asphalt, marked with
raised pavement markers
:- ,.
$$-$$$
• More costly traffic circles are made with curbing and back filled with asphalt __._
-
• The most expensive traffic circle to construct include curbing and removal of
.
existing asphalt from the center. Soil and approved landscaping are installedWNW/NM
�:
L{r IL Op
1
Chicane
• A series of tight turns in a straight section of road that restricts traffic speeds
.ti
$$-$$$
• Fire Code may limit chicanes or any other treatment from narrowing the road
to less than 20 feet
Ty
• Chicanes can be made of wooden traffic barricades, curbing with fencing,
curbing with asphalt back fill, or curbing with landscaping
• Can be combined with on -street parking
'"
_
,
y
t
Y
Speed Cushion
• A raised mound across the roadway that reduces speeds as vehicles
c'
$$
travel over them
.-*
Pi
m
• To be effective, should be placed 300-500 feet apart and installed in a r
ow
"'
Of
4r..
series of typically at least 2 cushions
• Not recommended on primary emergency response routes or on major
transit routes
i
--
1 1
,
1
, t
(p
'
Turn Prohibitor:
Signing
restrictions
• Signs are placed at intersection to restrict certain turning movements or to only allow a certain
• Restrictions can be all the time or can be during certain times of day only
movement
$-$$
Turn Prohibitor:
Physical deterrent
• Also known as half
• Physically directs
• Many variations can
• Can be combined
or
traffic
be
with
y/p�yM�pedestrian
partial closures or diverters
flow at intersections, prohibiting
implemented, depending on the
amenities such as textured
specific
need
movements
of the
pavement
particular street
or raised crosswalks
$$-$$$
II
Plirl
I
6i
)
v�:✓� ..;,,..,.f, �
r
�.�„..
._,..
T
es,
_
,::.
�;, T
F
-- ---
_.
4.
Diagonal Road
Closure
• Diagonal road closure completely closes a road to through traffic without
completely closing a road
• Diagonal diverters can be used to fully or partially divert traffic
• Implementation can be done by using wooden barricades, concrete
,p
$-$$$
11
barricades, curbing, and landscaping
• Diagonal diverters are not applicable in most places as minimum travel lane
widths of 20 feet must still be maintained
mm. :-
I.
Alit
Street Closure
• Streets are closed to through traffic by forming a cul-de-sac or44
$-$$$
hammerhead
• Additional right-of-way may be necessary to construct the cul-de-sac or
hammerhead
, tits
=
• Street closures are not applicable in most locations
iiiik° -gab
._._,
,e.
•,
'
s.
5i4
52
Method
Speed
Watch
Program
Potential
Degree of
Effectiveness
Mild
Advantages
• Educates residents on what the
legal speed limit "feels" like from a
pedestrian stand point.
Traffic Calming Methods
Disadvantages
• Does not reduce speeds or volumes.
- GENERAL
Volume
Reduction
No
Speed
Reduction
No
OVERVIEW
Noise &
Pollution
N/A
Safety
N/A
Access
Restrictions
N/A
Emergency
Vehicle
Access
N/A
Dependence
on Police
Enforcement
N/A
Operation
and/or
Construction
Cost
N/A
Maintenance
Cost/
Problems
N/A
Radar Speed
Trailer
Mild
• Educates motorists of their current,
actual speed of travel
• Makes motorists aware of the
activeness of the community they
are driving through.
• Only changes behavior in motorists while in
place.
• Some motorists use the reader board to "clock"
how fast they can go.
No
Only when
Present
N/A
N/A
N/A
N/A
None to High
Can be used in
conjunction
with target
enforcement
Low to
Moderate
Low
Target
Enforcement
Mild
• Reduces speeds and raises
awareness of drivers.
• Effective only when program is ongoing
• Staffing needs vary based on area specific
needs
Very Slight
Yes
N/A
Possibly
Improved
N/A
N/A
High
N/A
N/A
Striping
Mild
• Does not require infrastructure
construction
• Can promote slower traveling
vehicles
• Best in correcting vehicles traveling
in middle of road
• Can significantly reduce speeds of
users
• Not commonly used method of speed control
• Degree of effectiveness may vary substantially
Unlikely
Possible
N/A
Possibly
Improved
None
No Problem
N/A
Low
Low to
Moderate
Vegetation
Trimming
Mild
• Increases visibility.
• Must be constantly maintained
• Must be constantly monitored
No
No
N/A
Improved
N/A
N/A
N/A
Moderate
Moderate
Improved
Signage
Mild
• Corrects sign deficiencies
• Develop motorist awareness of
regulations and restrictions
• Requires monitoring and planning to avoid visual
clutter
• Probably not effective to habitual violator
Unlikely
Unlikely
Increased
visual
pollution
Possibly
Improved
N/A
N/A
Low to
Moderate
Low
Low
Traffic
Safety
Campaign
Mild
• Raises awareness, cooperation, and
appreciation of general motoring
public.
• City does not currently have a program
established
• Requires development of program and
continuation of staffing and program
• Impact may be reduced when "newness" of
program is lost
No
Possible
N/A
Slight
Improvement
N/A
N/A
N/A
Moderate
Low
Multi -way
Stop
Mild to
Moderate
• Creates more stopping points for
vehicles
• Addresses concerns at locations
with conflict potential
• Stop signs that are installed that don't meet
engineering warrants are often not obeyed by
motorists familiar with the intersection(s)
• Can reduces pedestrian safety if not correctly
installed
• Should not use Stop signs as speed control: stop
signs should be used to define right of way at
intersections only
Slight
Slight
Increased
Mixed
None
No problem
Moderate to
High
Low
Low
Gateway/
Entrance
Treatment
Moderate
• Provides visual transition between
arterials and residential areas
• Can improve pedestrian crossing
safety on wider streets
• Speed change could result in rear -end accidents
• May move traffic/problem to other roads
• Neglect of landscaping can become a sight
distance problems
• Neglect of landscaping can become
neighborhood "eyesores"
• Ongoing maintenance costs
• Definition of who is responsible for maintenance
- possible landscape maintenance agreements
with residents
Possible
Slight
No
Possibly
Improved
None
No Problem
N/A
Low to
Moderate
Low to
Moderate/
Possible
Vandalism
Pedestrian
Safety
Measures
Moderate
• Creates clearly defined areas for
pedestrians
• Provides safer areas for pedestrians
• Painted crosswalks could create a false sense of
security for pedestrians
• Pavement markings require additional
maintenance.
No
No
N/A
Mixed
None
No Problem
N/A
Moderate
Moderate
53
Method
Traffic Circle
Potential
Degree of
Effectiveness
Moderate
Advantages
• Requires reduction in vehicle speed
without use of stop signs
• Removes conflict potential for many
types of accidents
Traffic Calming Methods
Disadvantages
• May be restrictive for larger vehicles or vehicles
with trailers
• May move traffic/problem to other roads
• May require additional lighting
• May be confusing for left turns
• May require additional Right-of-way
• Requires consideration for aesthetics
• Requires consideration for maintenance of
landscaping, if used
- GENERAL
Volume
Reduction
Possible
Speed
Reduction
Likely
OVERVIEW
Noise &
Pollution
No
Change
Safety
Improved
Access
Restrictions
None
Emergency
Vehicle
Access
Some
Constraint
Dependence
on Police
Enforcement
Low
Operation
and/or
Construction
Cost
Moderate
Maintenance
Cost/
Problems
Moderate/
Possible
Vandalism
Chicane
Moderate
• Effectively slows motorists traveling
through and approaching the treated
section
• Can be designed to improve
pedestrian safety.
• Moves traffic/problem to other roads
• May be restrictive for larger vehicles or vehicles
with trailers
• May require additional lighting
• Can create confrontations between opposing
motorists
• Fire codes requirement must be maintained
• Requires consideration for aesthetics
• Requires consideration for maintenance of
landscaping, if used
Yes
Yes
Decrease
Mixed
None
Minor
Constraint
N/A
Moderate to
High
Moderate to
High/Possible
Vandalism
Speed Hump
Extreme
• Reduces speeds of vehicles at and
in the vicinity of the bump
• Can be designed for any speed
• Better if used in a series of 300 to
500 foot spacing.
• Causes increased noise from braking and
accelerating vehicles, particularly if there are
loose items in the vehicle
• May move traffic/problem to other roads
• Causes delays in emergency vehicle response
time
• Not supported by Fire Department
• Can cause damage to fire trucks during
emergency responses
Possible
Yes
Increase
at humps
Improved
None
Minor
constraint
Self Enforcing
Moderate
Moderate/
impacts street
sweeping,
snow removal
Turn
Prohibitor:
Signing
restrictions
Moderate
• Can reduces through traffic.
• Moves traffic/problem to other roads
• Inconveniences local residents in gaining access
to their property
• Becomes an enforcement problem
Yes
Possible
Decrease
Mixed
Somewhat
Restricted
Minor
Constraint
Moderate to
High
Low
Moderate/
Possible
Vandalism
Turn
Prohibitor:
Physical
deterrent
Extreme
• Reduces through traffic.
• Moves traffic/problem to other roads
• Inconveniences local residents in gaining access
to their property
• Can affect emergency vehicle response time
• Becomes an enforcement problem
Yes
Likely
Decrease
Improved
Restricted
Some
Constraint
Moderate to
High
Moderate to
High
Moderate/
Possible
Vandalism
Diagonal
Road
Closure
Extreme
• Eliminates through traffic
• Provides for landscaping
• Reduces conflicts
• Increases pedestrian safety.
• Not viable in most locations
• Moves traffic/problem to other roads
• Inconveniences local residents in gaining access
to their property
• Not generally supported by Fire Department
• Affects emergency vehicle response time
Yes
Likely
Decrease
Improved
Left or Right
turn only
Some
Constraint
Low to High,
dependent on
features
High
Moderate/
Possible
Vandalism
Street
Closure
Extreme
• Eliminates through traffic
• Can reduce speed of remaining
traffic
• Improves safety on the street closed
• Reduces accessibility of emergency vehicles
• Forces the problems onto another street
• Reduces access to properties by residents
Yes
Yes
Decrease
Improved
Yes
Some
Constraint
Low
Moderate to
High
Moderate to
High/Possible
Vandalism
54