HomeMy WebLinkAboutTSAC - Traffic Calming Policy 11-02-2009
Town of Lexington
Traffic-Calming Policy
November 2, 2009
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 Mass Highway 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 Mass Highway 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.
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
1
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
o
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
o
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 tocommittee) 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.
2
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:
3
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
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
4
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
Attachment A
is provided in .
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.
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
5
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.
Selection of Preferred Traffic Calming Plan.
1.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
o
Geometric constraints
o
Drainage requirements
o
Emergency service access
o
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.
6
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.
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
7
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.
8
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
9
Traffic Calming Measures
Descriptions and Pictures of
Traffic Calming Devices and Techniques
Devices and DescriptionsPictures
Techniques
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/ Curb extensions at
intersections that reduce
Chokers
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 Curb extensions that
Shiftsalternate from one side of
the roadway to the other,
forming s-shaped curves.
Closures (Cul-de-Barriers placed across
sacs) roadways to completely
close through vehicle traffic.
DivertersBarriers placed diagonally
across an intersection,
blocking certain
movements.
10
EducationInstructions given to the
residents on safe on-street
vehicle travel.
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.
RealignedChanges in alignments that
Intersectionsconvert T-intersections with
straight approaches into
curving roadways meeting
at right angles.
RoundaboutsBarriers 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.
11
Speed Tables/ Flat-topped speed humps
Textured Pavement/ often constructed with a
brick or other textured
Raised Crossings
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.
Sources: Traffic Calming, Selected Practices, Lessons Learned and Reed
Ewing, Rutgers University, Center for Urban Policy Research.
Previous Page | Next Page
This page last modified on October 24, 2001
FHWA Home | HEP Home | Traffic Calming Home | Feedback
United States Department of Transportation -
Federal Highway Administration
12