HomeMy WebLinkAboutPolicy-TrafficCalming-110209 1
BOARD OF SELECTMEN POLICY
TRAFFIC CALMING POLICY
Date Approved by BOS: Signature of Chair:
November 2, 2009 Norman P. Cohen
A. Statement of Traffic-Calming
The Town of Lexington is committed to:
Improving the livability and safety of Lexington neighborhoods by mitigating the impacts
of traffic and promoting safer conditions for residents, motorists, bicyclists, and
pedestrians;
Installing traffic calming measures on streets where their implementation will reduce
traffic speeds, minimize cut-through traffic where appropriate, or improve the safety of
movements by pedestrians and bicyclists;
Implementing traffic calming techniques that are both effective and compatible with the
character of the affected neighborhoods and improve public safety without jeopardizing
emergency response needs, creating hazards, or reducing mobility beyond acceptable
levels;
Encouraging citizen input in neighborhood traffic management;
Influencing driver behavior through education and design;
Ensuring that Town resources are utilized in a cost-effective and efficient manner.
To achieve these objectives, several procedures will be available depending on the nature and
potential funding of needed improvement. Requests may be initiated by Town boards,
committees, individuals or group entities. The Traffic Safety Advisory Committee (TSAC) will
be the main evaluator of traffic calming issues,. They may adopt written procedures that
supplement this Policy Statement, and will use the MassHighway Design Manual and Mass
Highway Traffic Calming Guidelines as a basis for review and evaluation, except that they may
supersede certain procedures and criteria by determining and publishing locally-based
modifications.
Streets in Lexington are defined by Mass Highway and further detailed by the Federal Highway
Department under the Federal functional classification system. The Town will identify candidate
streets by the MassHighway Area Type when warranted.
The Town may from time to time establish transportation plans for various sections of Town.
Such plans may include traffic calming provisions that will form the basis for specific traffic
calming implementations in that area.
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Neighborhood Traffic Calming on Local, Collector and Arterial Streets: The following
procedures will be followed when considering requests for and in developing, designing and
implementing neighborhood traffic calming measures on Lexington local, collector and arterial
streets. These procedures provide for the submittal of traffic calming requests and their
evaluation by Town Boards, staff or consultants, and approval by the Board of Selectmen; the
evaluation of alternative traffic calming measures and development of alternative plans by an
interdepartmental team; and the continued involvement and review of measures by the affected
neighborhood and appropriate Boards and Committees. These are general guidelines the Town
of Lexington will follow for traffic-calming requests, but cannot handle all traffic problems or
situations in town.
This policy addresses existing conditions on local roads and conditions that have evolved over
time.
The need for traffic calming measures as a result of new development and redevelopment
would be handled by the Special Permit Granting Authority and included within the
traffic studies and mitigation proposed for the project. Any new projects that are
proposed for development will consider traffic-calming on any streets that will be
impacted by the development. The SPGA is encouraged to get feedback from TSAC.
If a road is programmed for reconstruction, TSAC will look at the appropriate data to
determine if traffic-calming should be considered for that location.
B. Problem Identification and Needs Assessment
1. Request for Neighborhood Traffic Calming Measures: A preliminary request
containing signatures from at least ten households or 50% of the residences or businesses
on the street, whichever is less, shall be required for the town to begin consideration of a
traffic-calming plan. Preliminary requests for traffic calming measures on a specific
street or streets may be made by (a) a resident, with the required signatures; (b) a
business or property owner, with the required signatures; or (c) any Town Department,
board or committee All requests must be made in writing and forwarded to the Police
Department (Public Safety Officer) and TSAC (staff liason to committee) for
consideration. To the extent possible, each request should identify the street(s) or area of
concern and describe the nature of the problem.
2. Clarification and Preliminary Evaluation of Traffic Calming Requests: Upon receipt
of a request (and after the initial evaluation) for neighborhood traffic calming, the town
staff will forward the request to the Traffic Safety Advisory Committee (TSAC). The
TSAC will discuss the request at its next regular scheduled meeting. Prior to the TSAC
meeting, data will be collected and analyzed (if necessary, to be determined by Police
Department) by town staff on traffic speeds and accident reports. Staff may require
additional time to collect the data prior to the TSAC meeting.
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Following the discussion and analysis of the traffic and safety problems that triggered the
request, TSAC may determine that the request merits further consideration under these
procedures. If data that is collected and analyzed demonstrates a need for a Needs
Assessment (Section 3), then the project should move forward. If TSAC feels the data
does not support futher analysis, then the process is complete and the request for traffic-
calming is denied with the rationale for denial in writing.
If a request is made for traffic calming on an arterial, the toolbox of options will be
limited and will be decided on a case-by-case basis. Streets in Lexington are defined by
Mass Highway and further detailed by the Federal Highway Department under the
Federal functional classification system. The TSAC will consider the availability of
Town resources and give priority to addressing traffic and safety concerns in the
following areas:
Streets that provide access to a public or private school, or represent major walk-to-
school or bicycle-to-school routes;
Streets that are heavily traveled by pedestrian and bicycle populations seeking access
to a public park, public/government building, or private facility;
Streets that have been programmed for reconstruction in the near future and thereby
present opportunities to realize cost savings by undertaking all construction work
simultaneously.
If a road is already programmed for reconstruction, TSAC will look at the appropriate
data to determine if traffic-calming should be considered for that location. No additional
action may be required under this policy on requests that can be readily and consistently
addressed by the following traffic-calming measures: expanded enforcement of existing
traffic and parking regulations, and/or low-cost engineering and signage improvements,
and/or other on-going/planned projects. Town staff or its consultants will prepare a
Needs Assessment for those issues deserving further study and evaluation.
In the case of new development, the developer may be required to pay for traffic calming
on streets affected by the new development (and may also need to pay for the needs
assessment, plan development and public outreach).
3. Preparation of Needs Assessment: Following the initial review and data collection,
Town staff will develop and implement a scope of work designed to establish baseline
conditions in a clearly defined study area and more definitively describe the traffic or
safety problem(s) to be addressed. As appropriate, the following traffic data and
information may be collected and analyzed:
Street classification and Area Type
Traffic volumes (average weekly by direction for each street)
Traffic speeds
Posted speed limits and other signage
Physical data (# of lanes, width, grade and alignment, parking)
Location of nearest community facilities, schools, parks, and businesses
Accident data reports
Status of each street as emergency vehicle, bus, truck, or bicycle route
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Extent of cut-through traffic on street (if applicable)
Pedestrian crossing volumes (peak hours)
The study area will encompass all streets and intersections identified as problem areas, as
well as all reasonably adjacent streets and intersections that might be indirectly affected
by the diversion of traffic resulting from the installation of various traffic calming
measures. Consultant services may be retained, from time to time, to assist town staff in
the collection and evaluation of the necessary data and information.
Upon timely completion of the above data collection effort, a Needs Assessment Report
will be prepared and submitted to the TSAC. This report will summarize the findings of
the above field inventory and data collection effort. The baseline conditions described in
the Needs Assessment Report will provide the basis for the identification of those traffic-
calming measures likely to be most effective in addressing the traffic problems confirmed
to exist on each street(s).
4. Determination of Need: Based on the findings of the Needs Assessment, the TSAC will
determine if the conditions found warrant a detailed evaluation of alternative traffic
calming measures. There may be areas in which an increased police enforcement
presence, improved signage, and/or driver education will be sufficient to address the
problems identified by neighborhood residents and confirmed to exist by the Needs
Assessment. Where physical modifications to the roadway environment are determined
to be unnecessary, the town staff will work with neighborhood representatives to address
their concerns and no further review under this policy will be required. In the event that
traffic-calming measures are deemed necessary, a traffic calming plan development
process will be established.
C. Plan Development
1. Screening of Alternative Traffic Calming Measures: Based upon the findings of the
Needs Assessment, town staff (or its consultants) will identify and evaluate the
applicability and likely effectiveness of a variety of traffic calming measures
(individually and in combination) in addressing the identified traffic or safety problems
confirmed on each street. Alternative traffic calming measures will include, but may not
be limited to, such actions and devices as: chokers, neck downs, chicanes, center islands,
raised crosswalks, raised intersections, roundabouts, traffic circles, speed humps, speed
tables, textured pavement, one-way street designations, forced turn islands, median
barriers, curbing, striping, etc. A description of each measure is provided in Attachment
A.
The alternative traffic-calming measures will be evaluated using the best information
available on their applicability and effectiveness in addressing a specific problem, the
technical feasibility of installing the devices properly within the constraints of the
existing right-of-way, the relative costs of their construction, and the impacts they may
have on emergency vehicle access, drainage, and maintenance.
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A Traffic Calming Report that contains the findings of this evaluation will be prepared
and submitted to the TSAC. This report will identify the traffic calming measures
determined to be both feasible and effective in addressing the problems established in the
Needs Assessment. It will also identify the likely impacts on traffic flow, traffic speeds,
and different user groups that implementation of each feasible measure is likely to create.
Estimates of construction and maintenance costs will also be included in the report.
2. Development of Conceptual Traffic Calming Plans: Based on the information
collected in the screening report, town staff will develop a conceptual traffic calming plan
(or plans) for the impacted street(s). When developing alternative traffic-calming plans,
the following general guidelines will apply:
a. The Director of Public Works/Engineering or designee (in conjunction with the
Police and Fire Departments) will determine the design, location and spacing of all
traffic-calming measures (devices, signs, markings). All devices will be planned and
designed in conformance with sound engineering practices and standards, and in
consultation with other communities having experience with their implementation
and maintenance.
b. The parking needs of residents must be balanced with the equally important functions
of traffic, emergency vehicle access, and pedestrian safety. The design and
installation of traffic-calming devices should avoid the removal of parking spaces
wherever possible.
A traffic-calming plan report that contains the schematic plans including a preferred
plan will be prepared and submitted to the TSAC. This report will identify the type,
location, and design of those individual traffic-calming measures determined to be
both feasible and effective in addressing the traffic and safety problems found on the
specific street. Each optional traffic-calming plan will impose different types of
impacts and benefits on different groups, and will therefore require difficult tradeoffs
if selected for implementation.
Town staff will present the conceptual plan to the Board of Selectmen prior to finalizing the
plan.
D. Public Meeting
A public meeting will be held by the TSAC to review the alternative traffic calming plans and
seek further input on neighborhood preferences. The neighborhood input received at this public
meeting will be used to clarify the choices between alternative plans, and identify the extent to
which different user groups would either support or oppose their implementation.
Town staff will mail notification of this public meeting to all abutters (residents and businesses)
within 300 feet of proposed measure.
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1. Selection of Preferred Traffic Calming Plan. The TSAC will consider the comments
received at the public meeting in selecting a preferred traffic- calming plan that balances
the neighborhood protection objectives of those residing along the affected street(s) with
the mobility and economic development objectives of the town. When determining
which traffic control measures should be included in the preferred plan, the TSAC will
utilize the following criteria:
Expected benefits to safety and quality of life
Neighborhood preference
Maintenance needs
Cost of construction
Technical feasibility:
Space constraints
Geometric constraints
Drainage requirements
Emergency service access
If the installation of a specific traffic-calming device contained in the preferred traffic
calming plan allows for the use of optional materials differing in quality and cost, the
preferred traffic-calming plan selected by the TSAC must specify the definitive materials
to be used.
E. Plan Implementation and Evaluation
The recommended traffic-calming plan with preliminary cost estimates will be forwarded to the
Board of Selectmen for review and approval. The Town Engineer or designee will prepare
detailed design plans and cost estimates for each element of the approved plan. When
appropriate, implement measures on a temporary or trial basis for a pre-determined time to
confirm the effectiveness in addressing problems. This allows for adjustments and relocations
prior to full implementation. The bid and contract documents will be prepared and made
available to possible contractors. If the traffic-calming plan is part of a road reconstruction
project, the Town Engineer will designate the amount of funding for the approved traffic-
calming device.
The town staff will monitor implementation (and report back to TSAC) of the approved traffic-
calming plan for compliance with final design plans. To ensure that the approved traffic-calming
plan achieves its intended effect, the town staff will also evaluate the effectiveness of each
completed traffic-calming project within six months of device installation. This evaluation will
include, at a minimum, a review of the project’s impact on traffic volumes, vehicle speeds, and
safety.
Upon a finding by the Director of Public Works that a hazardous condition has been created by a
traffic-calming plan, such condition will be remedied by notifying the TSAC and immediately
modifying or removing the contributing traffic control device or devices. Property owners,
residents and occupants of properties in the area impacted may also request removal of a traffic-
calming device or devices by submission to the TSAC of a petition describing their specific
concerns. The TSAC will review the conditions surrounding said petition at a public meeting
and recommend appropriate action to remedy all legitimate safety concerns.
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F. Definitions
1. Minor residential street (not a through way): the lowest classification of residential street
designed to serve not more than four proposed, potential or existing dwelling units. It
carries only the traffic that has its origin or destination on the lots, which have access to
the street. In nearly every case, the limitation of not more than four proposed, potential
or existing dwelling units served means the street will be a dead end.
2. Local street: the next lowest street designed to serve five to fourteen proposed, potential
or existing dwelling units. It carries traffic that has its origin or destination in the
immediate neighborhood, such as on the lots that have access to the street and from minor
residential streets, which connect to it. “Not a through way” streets with more than five
proposed, potential or existing dwelling units are classified as local streets.
3. Collector street: Streets designed to serve 15 or more existing, proposed or potential
dwelling units, or a commercial development in a commercial subdivision, and to act as a
connection to other streets. It conducts and distributes traffic between lower
classification streets and higher classification streets. In larger residential developments,
a collector street may be necessary to carry traffic from one neighborhood to another
adjoining neighborhood or from the neighborhood to other areas in the Town.
4. Arterial street: the highest classification street designed primarily to carry through-traffic
that does not have its origin or destination within a proposed subdivision. It carries
traffic to and from commercial districts within Lexington, residential neighborhoods in
Lexington that are a mile or more away, and to and from activity centers in adjoining
cities and towns. Private access and frontage should be discouraged and limited to higher
volume generators of traffic such as large commercial or multifamily residential
developments.
5. Traffic Calming Plan: a combination of traffic management measures determined from an
appraisal of traffic conditions to be effective and feasible in reducing vehicle speeds or
traffic volumes and enhancing safety on a specific street or streets.
6. Traffic Count: a manual or automated count of the number of vehicles traversing a
specific point in a given time period. When necessary, the number of vehicles may be
broken down into vehicle classes (i.e. cars, trucks) and include bicycles and pedestrians.
7. TSAC: Traffic Safety Advisory Committee
8. Traffic Calming: The combination of policies and measures that help correct the negative
effects of motorized vehicle use on individuals and society in general by changing the
design and role of streets to serve a broad range of transportation, social and
environmental objectives.
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Attachment A: Description of Traffic-Calming Measures
1. Speed Humps: Speed humps are raised devices, parabolic in shape, placed across the road
to slow traffic. They are often considered the most traditional traffic calming solution.
Speed humps slow traffic more gradually than speed bumps, although less so than speed
tables.
2. Traffic Logix rubber solutions: specifically designed to be used on a permanent basis.
Engineered to perform without deforming, are sturdy, long lasting, highly visible, and can
withstand large traffic volumes continuously.
3. Speed Tables: Flat-topped speed humps, which are generally, long enough for the entire
wheelbase of a passenger car to rest on top. The design of speed tables allows for more
gradual slowing of vehicle speed than humps. This makes speed tables the ideal solution
for roads with typical residential speed limits.
4. Curb Extension/Medians: Curb extensions can be used to create a variety of horizontal
traffic-calming measures such as roundabouts, chicanes, neck downs and chokers.
5. Speed Cushions: Speed cushions are the newest available traffic-calming device, and
perhaps the most innovative. They have several distinct advantages. Designed as three
small speed humps, speed cushions force pedestrian vehicles to slow down. However,
the wider axle of emergency vehicles allows them to pass without slowing down. In
addition, speed cushions are more affordable than speed humps or tables since they
require less material.
6. Neighborhood traffic circles (roundabouts): Raised islands, placed in the middle of an
intersection, directing all traffic in the same direction. Usually larger than roundabouts.
7. Chicane: A series of narrowing or curb extensions that alternate from one side of the
roadway to the other, forming s-shaped curves.
8. Choker: Curb extensions at midblock or intersection corners that narrow a street by
extending the sidewalk or widening the planting strip.
9. Center island narrowing: Raised islands located along the centerline of a roadway that
narrow the width at that location.
10. Bulbouts/Neckdowns: Curb extensions at intersections that reduce curb-to-curb roadway
travel lane widths.
11. Diverters: Barriers placed diagonally across an intersection, blocking certain movements.
12. Forced Turn Lanes: Raised islands located on approaches to an intersection that block
certain movements.
13. 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.
14. Police Enforcement: Employing the services of law enforcement agencies to impose the
local safe vehicle laws, including those for posted speeds and traffic signal/signs.
Sources: U.S. Department of Transportation Federal Highway Administration
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Traffic Calming Measures
Descriptions and Pictures of
Traffic Calming Devices and Techniques
Devices and
Techniques
Descriptions Pictures
Bike Lanes A portion of a roadway, which has
been designated by striping,
signing, and pavement markings
for the preferential or exclusive
use of bicyclists.
Bulbouts/Neckdowns/
Chokers
Curb extensions at intersections
that reduce curb-to-curb roadway
travel lane widths.
Center Islands Raised islands located along the
centerline of a roadway that
narrow the width at that location.
Chicanes/Lateral
Shifts
Curb extensions that alternate
from one side of the roadway to
the other, forming s-shaped
curves.
Closures (Cul-de-
sacs)
Barriers placed across roadways
to completely close through
vehicle traffic.
Diverters Barriers placed diagonally across
an intersection, blocking certain
movements.
Education Instructions given to the residents
on safe on-street vehicle travel.
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Forced Turn Lanes Raised islands located on
approaches to an intersection that
block certain movements.
Median Barriers Raised islands located along the
centerline of a roadway and
continuing through an intersection
to block cross traffic.
Police Enforcement Involve employing the services of
law enforcement agencies to
impose the local safe vehicle laws,
including those for posted speeds
and traffic signal/signs.
Realigned
Intersections
Changes in alignments that
convert T-intersections with
straight approaches into curving
roadways meeting at right angles.
Roundabouts Barriers placed in the middle of an
intersection, directing all traffic in
the same direction.
Speed Humps Rounded raised pavement devices
placed across roadways to slow
and/or discourage traffic.
Speed Tables/
Textured Pavement/
Raised Crossings
Flat-topped speed humps often
constructed with a brick or other
textured material to slow traffic.
Traffic Circles Barriers placed in the middle of an
intersection, directing all traffic in
the same direction. Usually larger
than roundabouts.
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Sources: Traffic Calming, Selected Practices, Lessons Learned and Reed Ewing,
Rutgers University, Center for Urban Policy Research.
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