Prattville Traffic Calming Policy Draft
DRAFT
Draft
Neighborhood Traffic Calming Policy
City of Prattville, AL
The Neighborhood Traffic Calming Policy is intended to aid citizens in resolving
traffic problems in residential areas. This policy has been formed to encourage
citizen involvement in neighborhood traffic management activities. Issues such as
reducing the average speed of traffic and minimizing vehicular traffic on local
neighborhood streets require careful study.
The following procedures are considered typical for receiving, responding to, and
managing citizens’ requests for traffic management on their streets or in their
neighborhoods. Variations in this process may be approved by the City Engineer
when deemed appropriate due to unique circumstances. The following step-by-
step procedures are shown graphically in Appendix A.
Procedures
Step 1: Community Support
A resident who desires to present neighborhood traffic problems or concerns to
the City is encouraged to complete a Traffic Calming Request Form and submit it
to the City Engineer’s office. The Form requires at least one resident’s signature,
but additional spaces are provided for others from the affected area as well. If
the residences along the street are part of an active Homeowner’s Association
(HOA), the Form should be completed by a representative of the HOA.
Step 2: Initial Review
After receiving the Traffic Calming Request Form, the City’s engineering staff will
conduct an initial review of the requested street. The following criteria will be
evaluated to determine whether further consideration and evaluation of traffic
calming measures is warranted:
Minimum Criteria for Initial Review*
•
•
•
•
The posted speed limit is 30 MPH or less.
The roadway width is 20 feet or more.
The distance between stop signs and curves must be greater than 600
feet.
The roadway must be classified as a local street and not functioning as
a through road.
*-unless approved by the City Engineer
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Once the initial review has been completed, the City will notify the resident who
submitted the Form of the eligibility of the street for further consideration and
evaluation.
Step 3: Data Collection and Analysis
The Engineering Department will perform any necessary data collection and
analysis to assess and quantify the traffic and safety conditions in the
neighborhood. The Engineering staff will identify the tentative study area, collect
preliminary information from their files and other potentially affected agencies,
and complete any needed traffic analysis. The following guidelines will be used in
evaluating the magnitude of traffic and safety problems, potential for
improvement using traffic calming techniques, and establishment of priorities for
project implementation.
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• Vehicular Volume
o Potential traffic calming sites should have a minimum of 150 vehicles
per day and a maximum of 2,000 vehicles per day. Sites with volumes
outside of this range may be considered at the discretion of the City
Engineer.
• Speed
o Only sites with 85th percentile speeds that exceed the posted speed
limit by 5 MPH or more will be considered for traffic calming measures.
• Functional Classification
o Traffic calming measures should only be considered for local routes.
• Crashes
o Crash data should be examined for a 3-year period. Crash history is
considered significant when there are 3 or more auto-involved
reported crashes across any 1-year period. If a site has 1 crash that
involved a pedestrian or bicycle, then that should also be
considered significant.
• Cut Through Traffic
o A vehicle that detours through a neighborhood for the convenience
of decreasing the amount of time it takes to reach a destination is
known as cut through traffic. The volume of cut through traffic is
typically quantified by estimating the expected traffic generated by
a neighborhood based on the Institute of Transportation Engineers
(ITE) Trip Generation Land Use 210-Single Family Housing. The
expected daily volume is divided by the actual daily traffic volume
to calculate the percent of cut through traffic. The maximum
acceptable percentage of cut through traffic is 25% for local roads
and 50% for collector routes.
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• Street Grades and Alignment
o Traffic calming measures that cause vertical deflections (speed
humps, speed tables, etc.) are not typically installed on streets with
grades exceeding 8%, or where a combination of vertical and
horizontal alignment would result in inadequate stopping sight
distance for motorists encountering traffic calming measures.
• Transit, School, and Emergency Routes
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o Traffic calming measures are not typically installed on streets serving
as designated transit routes or primary emergency access routes.
o School authorities should be consulted in conjunction with proposed
traffic calming measure implementation if a school route is being
considered for improvement.
• Grading System
o A combination of traffic volume and 85th Percentile Speed of traffic
will be used in the evaluation by using the Grading System shown
below.
▪Points acquired from the Daily Traffic Volumes will be added to
the points acquired from the 85th Percentile Speeds. A total of
6 points will be required to move on to the next step.
▪Streets that do not have sidewalks on at least one side are
given 1 additional point beyond that which is calculated from
the Grading System Criteria table.
▪Locations within ½ mile of a school are given 1 additional point
beyond that which is calculated from the Grading System
Criteria table.
▪Locations with significant pedestrian activity are also given 1
additional point beyond that which is calculated from the
Grading System Criteria table.
▪Note: Historical crash data will also be analyzed in conjunction
with traffic calming evaluation, but crashes alone do not
confirm the need for traffic calming improvements.
0 - 150 Not Eligible 0 - 4 MPH Not Eligible*
151 - 300 1 5 MPH 1
301 - 500 2 6 MPH 2
501 - 700 3 7 MPH 3
701 - 1,000 4 8 MPH 4
1,001 - 2,000 5 9 MPH 5
2,001+ Not Eligible* 10+ MPH 6
Daily Traffic Volumes 85th Percentile Speeds (over speed limit)
Grading System Criteria
* - unless approved by City Engineer
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• Improvement Tiers
o In addition to the grading system, a tiered approach will also be
utilized in selecting improvement measures. As the point total
obtained from the Grading System Criteria increases, a greater
number of traffic calming measure options will become available.
▪For example, if the Grading System Criteria process yields 8
points, all traffic calming measure options shown under the 6-
point, 7-point, and 8-point lists will be available for
consideration.
• 6 Points • 8 – 9 Points
o Speed Hump o Chicane
o Speed Table o Traffic Circle
o Raised Crosswalk o Raised Intersection
o On-Street Parking o Realigned Intersection
o Road Diet (striping) o Road Diet (non-striping)
o Speed Feedback • 10 Points
Signs o Roundabout
• 7 Points
o Mini-Roundabout
o Bulb-Outs/Curb
Extensions
o Choker
o Median Island
Step 4: Evaluation and Determination
Utilizing the information gathered from analysis and speed studies, the City
Engineer will determine the type of device to be installed. Common device
categories include those offering vertical deflection, horizontal deflection, and
street width reduction. Additional information regarding the listed traffic calming
devices can be found in the Institute of Transportation Engineers’ (ITE) Traffic
Calming resources or the Federal Highway Administration’s (FHWA) Traffic
Calming ePrimer. The following are traffic calming measures that could be
considered for a potential site:
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Vertical Deflection
Draft
Speed Hump
• Rounded (vertically along travel path) raised
areas of pavement typically 12 to 14 feet in
length
• Often placed in a series (typically spaced 260
to 500 feet apart)
• Appropriate for mid-block placement, not at
intersections
Source: FHWA Traffic Calming ePrimer
Speed Table/Raised Crosswalk
• Long, raised speed humps with a flat section in
the middle and ramps on the ends
• Appropriate for mid-block or at intersections,
with/without crosswalks
• If placed at a pedestrian crossing, it is referred
to as a raised crosswalk
Source: ITE.org
Raised Intersection
• Flat raised areas covering entire intersections,
with ramps on all approaches and often with
brick or other textured materials on the flat
section and ramps
• Typically installed at signalized or all-way stop
controlled intersections with high pedestrian
crossing demand
Source: FHWA Traffic Calming ePrimer
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Horizontal Deflection
Draft
Source: FHWA Traffic Calming ePrimer
Chicane
• A series of alternating curves or lane shifts that force
a motorist to steer back and forth instead of
traveling a straight path
• Appropriate for mid-block locations
Source: ITE.org
Traffic Circle
• Raised islands placed in unsignalized intersections
around which traffic circulates
• Approaching motorists yield to motorists already in
the intersection
• Approaches not designed to modern roundabout
principals -no deflection
Source: ITE.org
Mini-Roundabout
• Raised islands, placed in unsignalized intersections,
around which traffic circulates
• Motorists yield to motorists already in the intersection
• Center island of mini roundabout is fully traversable,
splitter islands may be fully traversable
Source: ITE.org
Roundabout
• Raised islands placed in unsignalized intersections
around which traffic circulates
• Different from traffic circles or
mini roundabouts; possible substitute for traffic signal
control
Source: ITE.org
Realigned Intersection
• Reconfiguration of an intersection with
perpendicular angles to have skewed approaches
or travel paths through the intersection
• Most applicable at T-intersections
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Street Width Reduction
Draft
Source: ITE.org
Bulb-Out/Corner Extension
• Horizontal extension of the sidewalk into the
street, resulting in a narrower roadway
section
• When combined with on-street parking, a
corner extension can create protected
parking bays
• Effective method for narrowing pedestrian
crossing distances and increase pedestrian
visibility
Source: FHWA Traffic Calming ePrimer
Choker
• Curb extension is a lateral horizontal
extension of the sidewalk into the street,
resulting in a narrower roadway section
• Encourages lower travel speeds by
reducing motorist margin of error
• May be suitable for a mid-block crosswalk
Source: ITE.org
Median Island
• Raised island located along the street
centerline that narrows the travel lanes at
that location
• Can often double as a pedestrian/bicycle
refuge islands if a cut in the island is
provided along a marked crosswalk, bike
facility, or shared-use trail crossing
On-Street Parking
• Allocation of paved space to parking
• Can apply on one or both sides of roadway
• Can be combined with other traffic
calming measures
• Can apply alternating sides of street for
chicane effect
Source: FHWA Traffic Calming ePrimer
Source: ITE.org
Road Diet
• Revision of lane use or widths to result in
one travel lane per direction, with goal of
reducing cross-section
• Common applications include installation
of two-way left-turn lanes or bike lanes
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Miscellaneous
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Speed Feedback Sign
• Dynamic signs intended to reduce vehicle
speeds by making drivers aware of their speed
relative to the posted speed limit
• May be permanent or temporary installations
Source: FHWA
Step 5: Petition
If physical traffic calming measures are warranted, a neighborhood petition from
the “affected area” is required, and the City Engineer will notify the representative
of this additional requirement. The “affected area” is defined as those properties
along streets expected to receive traffic calming measures, those streets whose
access is substantially dependent upon the streets to be calmed, and any streets
expected to receive significant increase in traffic volume or type as a result of the
traffic calming measures installation. The City Engineer shall be responsible for final
approval of the “affected area” to be petitioned.
When a proposed technique is approved, the City Engineer will prepare a petition
package to be circulated by the Applicant. The petition will include the name
and address of each of the property owners in the affected area as well as the
description and detail of the proposed technique. The Applicant can pick up the
petition package or arrange to have it mailed.
It is the responsibility of the representative to circulate the petition within the
affected area. The petition must be delivered (in a legally accepted manner) or
offered to all property owners in the affected area. A positive response must be
obtained by sixty-six (66%) percent or more of the total number of properties in
the affected area to proceed further with the traffic calming project design and
implementation. The petition must be returned to the City Engineer within three
(3) months of receipt of the petition package by Applicant. At the request of the
representative, the City will circulate the petition in the form of mail-out postcards.
A positive response of sixty-six (66%) percent or more must still be achieved. Those
properties that do not submit a response after three (3) attempts by the City will
be counted as a negative response.
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Step 6: Project Design and Implementation
Once the completed petition reflecting a positive response has been returned,
the City Engineer will make the final recommendation to the City Council Street
Committee. The City Council Street Committee will place the item on the agenda
for consideration by the City Council. If approved by the City Council, the project
will be scheduled for construction by the Engineering Department.
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The installation cost of calming techniques may be shared with the City and the
neighborhood requesting the technique. If the City’s standard materials are used,
there will be no cost to the neighborhood. If decorative or non-standard measures
are desired, the neighborhood will incur the additional cost for the specialty items.
Attachments to be included:
Appendix A: Traffic Calming Procedure Flow Chart
Appendix B: Traffic Calming Request From
Appendix C: Traffic Calming Petition Form
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Appendix A
Flow Chart for Neighborhood Traffic Calming Policy Procedures
Draft
Step 1
Community Support
Step 2
Initial Review
Meets
Minimum
Criteria
Fails to
Meet
Minimum
Criteria
Project Not Eligible
for Traffic Calming
Education &
Enforcement Does Not
Meet
Specific
Study Criteria Meets
Specific
Study Criteria
Step 3
Data Collection &
Analysis
Step 4
Evalua ion &
Determination
Step 5
Petition
Petition
Fails
Petition
Passes
Education &
Enforcement
Step 6
Project Design &
Implementation