ROAD SAFETY AUDIT
Minot’s Corner
Town of Westford
January 2011
Prepared for:
Massachusetts Department of Transportation
Prepared by:
Howard/Stein-Hudson Associates
38 Chauncy Street
Boston, MA 02111
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Table of Contents Background .................................................................................................................................2
Project Data.................................................................................................................................2
Project Location Description .....................................................................................................3
Road Safety Audit Observations ...............................................................................................6
Safety Issue #1.
Safety Issue #2.
Safety Issue #3.
Safety Issue #4.
Intersection Geometry and Operations ............................................................... 7
Signage and Pavement Markings...................................................................... 13
Pedestrian Accommodations............................................................................. 16
Bicycle Accommodations ................................................................................. 18
Potential Safety Enhancements ...............................................................................................19
List of Appendices
Appendix A.
Appendix B.
Appendix C.
Appendix D.
Appendix E.
25% Design Plans
RSA Meeting Agenda
RSA Audit Team Contact List
Detailed Crash Data
Additional Information
List of Figures
Figure 1.
Locus Map.............................................................................................................................. 4
List of Tables
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Participating Audit Team Members ....................................................................................... 3
Proposed Geometric and Operations Enhancements............................................................ 11
Proposed Signage and Pavement Marking Enhancements................................................... 15
Proposed Pedestrian Enhancements ..................................................................................... 17
Summary of Potential Safety Enhancements ....................................................................... 20
Page 1
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Background
The intersection of Littleton Road (Route 110)/Boston Road/Carlisle Road (“Minot’s Corner”), located in
the Town of Westford, Massachusetts, is listed in the Top 5% of High Crash Locations within the
Northern Middlesex Council of Governments (NMCOG) area and is ranked #163 of the Top 200 High
Crash Intersection Locations 2006-2008 in Massachusetts. The Massachusetts Department of
Transportation (MassDOT) has determined that the Town would be eligible to receive Highway Safety
Improvement Program (HSIP) funding for reconstruction of this intersection if a Road Safety Audit
(RSA) were conducted and the proposed design incorporated safety improvements identified in the RSA.
The RSA is intended to identify potential safety improvements that can be evaluated and included as part
of the design process for the reconstruction. The short-term, low-cost potential improvements should be
considered by the responsible agency for implementation prior to reconstruction.
The intersection is currently at the 25% design stage, funded by the Town, and is being redesigned as part
of a larger project that would include the reconstruction of approximately 3,100 feet of roadway along
Route 110 between Minot’s corner and Nixon Road. However, during the RSA, the team focused on
safety issues and the safety benefits of the proposed improvements at Minot’s Corner. The 25% design
plan for the intersection is provided in Appendix A.
Project Data
The audit team conducted an RSA for Minot’s Corner on Monday, January 10, 2011. The RSA agenda
appears in Appendix B. Table 1 lists the audit team members and their affiliations. Appendix C
provides contact information for all team members.
Page 2
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Table 1. Participating Audit Team Members
Audit Team Member
Paul Starratt
Fred Palmer
Jeremy Downs
Michael Croteau
Justin Howard
Sarah Bradbury
David Tilton
Alan Cloutier
Michelle Daigle
Joshua Grzegorzewski
Azad Kidher
Chris Hogan
Lou Llaneza
Bonnie Polin
Lisa Schletzbaum
Keri Pyke
Joe SanClemente
Alexandra Siu
Agency/Affiliation
Town of Westford, Town Engineer
Town of Westford Planning Board
Town of Westford
Town of Westford Police Department
Northern Middlesex Council of Governments (NMCOG)
Northern Middlesex Council of Governments (NMCOG)
Northern Middlesex Council of Governments (NMCOG)
Fay, Spofford & Thorndike (FST)
Federal Highway Administration
Federal Highway Administration
MassDOT – Project Management
MassDOT
MassDOT
MassDOT Highway Division, Safety Section
MassDOT Highway Division, Safety Section
Howard/Stein-Hudson Associates
Howard/Stein-Hudson Associates
Howard/Stein-Hudson Associates
Project Location Description
The intersection of Littleton Road (Route 110)/Boston Road/Carlisle Road (“Minot’s Corner”) is located
in the Town of Westford, as shown in the aerial image in Figure 1 and operates under traffic signal
control. The intersection is located approximately 600 feet south of I-495 (exit 32).
Within the study area, Route 110 serves as a major east–west roadway that parallels I-495 and provides
access to numerous commercial and office uses, primarily concentrated to the east of Minot’s Corner on
both the north and south side of the roadway. Commercial uses are also located on all four corners of the
intersection.
Page 3
Road Safety Audit–Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Locus Map
RSA Study Area
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Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
The intersection of Littleton Road (Route 110)/Boston Road/Carlisle Road (“Minot’s Corner”) forms the
junctions of the following roadways, which are categorized according to MassDOT Office of
Transportation Planning functional classifications:
Littleton Road (Route 110) is an urban minor arterial and falls under MassDOT jurisdiction. Littleton
Road is an east–west roadway and is dedicated as Route 110. Within the study area, Littleton Road
generally consists of 1 lane in each direction; however the roadway widens in the vicinity of the
intersection to allow for turning lanes at the intersection approaches and for several of the adjacent
commercial businesses. The speed limit along Littleton Road is 35 miles per hour (mph) per the speed
regulations for the area.
Boston Road is an urban minor arterial and is owned by the Town. Boston Road generally runs north–
south between Main Street and Littleton Road and provides access to I-495 at Exit 32. Boston Road
consists of 2 travel lanes in the northbound direction and 3 lanes in the southbound direction between
Littleton Road and the exit ramps for I-495.
Carlisle Road is an urban minor arterial and is owned by the Town. Carlisle Road generally runs north–
south and consists of one lane in each direction in the vicinity of the intersection. The speed limit is
posted at 30 mph.
As detailed in the Littleton Road (route 110) from Minot’s Corner to Nixon Road Functional Design
Reported, prepared by FST in July 2009, the area is expected to experience a substantial amount of
commercial, office, and residential development, and re-occupancy of currently vacant office/commercial
spaces, over the course of the next 10 years. Future developments in the area include the Cornerstone
Square mixed-use project, which will be provided with an access driveway approximately 300 feet north
of the Minot’s Corner along Boston Road and a second driveway approximately 850 feet west of Minot’s
Corner along Littleton Road. In an effort to accommodate the projected increases in traffic volumes
associated with the various planned/permitted development in the area, the 25% design plans currently
propose to add an additional travel lane in each direction along Littleton Road and additional turning
lanes at each of the intersection approaches. The proposed plans also make provision for the addition of a
third Littleton Road eastbound left-turn lane at the intersection with Boston Road, if warranted by actual
future traffic volumes.
Prior to the RSA, in order to begin assessing possible safety issues, the team reviewed collision diagrams
and a crash detail summary based on crash records supplied by the Westford Police Department. Of
40 crashes related to the intersection from September 2008 through October 2010, 18 (approximately
45%) were rear-end type crashes, 13 (approximately 33%) were angle type crashes, and 8 (approximately
20%) were sideswipe crashes. Crashes generally occurred on dry pavement (36, or nearly 90%) in clear
weather conditions (32, or 80%) and during daylight hours (27, or 68%). Appendix D provides the
detailed intersection crash data from September 2008 through October 2011. Speed regulations and
traffic volume data are presented in Appendix E.
Page 5
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Road Safety Audit Observations
Based on field observations on Monday, January 10, 2011, the RSA team determined that the intersection
of Littleton Road (Route 110)/Boston Road/Carlisle Road has the following issues that affect safety:






Intersection geometry;
Sight distance;
Access management;
Signage clutter and clarity;
Limited pedestrian accommodations; and
Limited bicycle accommodations.
The following sections describe in more detail the safety issues and enhancements determined during
the RSA. These safety enhancements are also discussed as they relate to both the existing conditions and
the design plans which are currently at the 25% design level. Several of these issues require further study
and engineering judgment to determine the feasibility of implementing enhancements to address them.
Page 6
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Safety Issue #1. Intersection Geometry and Operations
Observations:
The intersection of Littleton Road (Route 110)/Boston Road/Carlisle Road is a 4-way signalized
intersection. The Littleton Road eastbound approach consists of 2 exclusive left-turn lanes and 1
shared through/right-turn lane and the Littleton Road westbound approach consists of 1 exclusive
left-turn lane, 1 through lane, and 1 free-right turn lane. The Carlisle Road northbound approach
intersects Littleton Road from the south on a vertical incline, at a slight angle, and consists of 1
shared left-turn/through lane and 1 shared through/right-turn lane. The Boston Road southbound
approach intersects Littleton Road from the north at an obtuse angle and consists of 1 exclusive
left-turn lane, 1 through lane, and 1 exclusive right-turn lane.
The RSA team noted the following observations related to intersection geometry:
Traffic Signal Visibility
RSA team members noted that the
visibility of the traffic signal
indications on the Carlisle Road
northbound approach is limited due to
the horizontal curvature of the
roadway and the presence of
obstructions on the southeast corner of
the intersection. Two traffic signal
indications are provided for the
northbound approach as required by
the Manual on Uniform Traffic
Control Devices (MUTCD), including
an overhead traffic signal indication
positioned along the left side of the
Visibility of traffic signal indications is limited along
Carlisle Road northbound approach.
approach and a second post-mounted
indication located on the northeast
corner of the intersection. The post-mounted indication is located such that it is not visible to
motorists until they are at, or near, the stop line due to the horizontal curvature of the roadway
and the presence of sign posts and a span wire pole on the southeast corner of the intersection.
The MUTCD recommends that “the two signal faces required for each approach should be
continuously visible to traffic approaching the traffic control signal”; however, while both signals
indications are visible (i.e., within the cone of vision) from the stop line, only the overhead
indication is visible upstream of the intersection. According to Police records from September
2008 through October 2010, 4 crashes (or 10%) occurred at the northbound approach; 2 of these
crashes were rear-end type. Limited visibility of the traffic signal indications along Carlisle Road
northbound may have contributed to the rear-end collisions.
Page 7
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Sight Distance
The RSA team noted 2 locations where sight distance limitations may have contributed to the
crash history at the intersection.
The Littleton Road westbound approach is provided with a free right-turn lane that is separated
from the westbound through lane with a landscaped island. RSA team members noted that
landscaping, signage, and a monument on this island inhibit sight lines between vehicles making
the right-turn along Littleton Road westbound and those traveling along Carlisle Road
northbound. According to crash
records, 3 crashes were reported
involving vehicles within the free
right-turn lane at the Littleton Road
westbound approach; 2 of these
crashes were rear-end type and 1 was
a sideswipe. Limited sight distance at
this location may have contributed to
the occurrence of these crashes as
motorists may have difficulty judging
a safe gap in the Carlisle Road
northbound traffic stream.
Landscaping, signage, and a monument inhibit sight
lines on northeast corner.
The second area of limited sight distance at the intersection is the Littleton Road eastbound
approach, which experienced 3 rear-end type crashes from September 2008 through October
2010. During the RSA, team members noted that sight lines to the west of the intersection are
limited due to a horizontal curve in the alignment of Littleton Road, which reduces the visibility
of the traffic signal indications and the vehicle queues at the intersection approach, which may be
a contributing factor to these crashes.
Access Management
At the intersection of Littleton Road (Route 110)/Boston Road/Carlisle Road, commercial uses
are located on all four corners of the intersection, including gas stations on the northwest,
northeast, and southeast corners of the intersection and a drug/convenience store on the southwest
corner of the intersection resulting in numerous curb cuts in close proximity to the intersection.
According to crash records, 9 crashes (or approximately 23%) occurred at driveways serving
these uses.
RSA team members noted that the curb cut on Boston Road providing access to the Gulf gas
station located on the northeast corner of the intersection is only approximately 65 feet north of
the Littleton Road westbound free right-turn lane; a second curb cut is also provided
Page 8
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
approximately 125 feet north of the Littleton Road westbound right-turn lane. Due to sight
distance limitations on the Littleton Road westbound right-turn lane, as described above,
motorists making a westbound right-turn onto Boston Road may not expect, or have time to
perceive and react to, vehicles exiting the Gulf gas station. One crash was reported involving a
vehicle traveling northbound on Boston Road and a second vehicle exiting the Gulf gas station.
RSA team members discussed the possibility of relocating, and/or reconfiguring, the curbs cuts
providing access to the Gulf station along Boston Road to provide a larger separation between the
driveways and the Littleton Road westbound right-turn lane.
A scored concrete area has been provided at the Gulf gas station driveway in an effort to
discourage left-turn turns onto Boston Road. However, the RSA team noted that the scored area
is ineffective at physically prohibiting this movement.
And lastly, the Mobil gas station, located
on the northwest corner of the
intersection, is constructed on a higher
elevation than Littleton Road and Boston
Road resulting in a steep vertical grade
change at the driveways accessing the site;
one driveway is located approximately
125 feet west of the intersection on
Littleton Road and a second driveway is
located approximately 100 feet north of
the intersection on Boston Road. RSA
team members noted that the grade change
at the driveways result in vehicles entering
or exiting the gas station at a slower rate
Mobil driveway on Boston Road has a steep vertical
incline and ineffective median.
of speed in an effort to avoid scraping the
bottom of their vehicle, which creates
additional friction along Littleton Road and Boston Road. One crash was reported involving a
single vehicle traveling eastbound on Littleton Road and turning left into the Mobil gas station;
the bottom of the vehicle was scraped. RSA team members also noted that the median in the
center of the Mobil gas station driveway on Boston Road is difficult for motorists to see and is
ineffective at deterring left-turns.
Page 9
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Design-Specific Comments:
The RSA team noted the following with respect to the proposed 25% Design Plans:
1. The receiving lanes for Littleton Road eastbound double left-turns and the Boston Road
southbound double left-turns appear to be constrained to accommodate heavy vehicle
turning radii; heavy vehicles are prevalent at this intersection due to the proximity to
commercial businesses and Interstate 495. The designer needs to ensure that the
receiving lanes are wide enough to prevent sideswipes.
2. The current design plans allow for the future addition of a third left-turn lane on the
Littleton Road eastbound approach at Boston Road/Carlisle Road. As noted in #1, the
designer should ensure that adequate right-of-way is preserved to accommodate heavy
vehicle turning radii should this additional turning lane be needed.
3. RSA team members raised concern about weaving between the intersection and the I-495
ramps and how the addition of the third Littleton Road eastbound left-turn lane would
function and if additional guide signage would be necessary.
4. The current design has a skew in the proposed alignment of Boston Road in the
northbound direction between approximately Station 106 and Station 108 likely due to
the transition required for the proposed second southbound left-turn lane pocket and to
avoid a pump house building located along the east side of the roadway. RSA team
members noted that the taper length seemed short, which may make it difficult for
motorists to stay in the correct lane, particularly if pavement markings are worn in the
future.
5. The current design plans propose to allow Littleton Road westbound U-turns to occur
during the protected left-turn phase concurrent with the pedestrian phase. While U-turns
are not expected to be a heavy movement on this approach, the designer should consider
the appropriateness of either prohibiting the U-turn movement or adding a “Turning
Traffic Must Yield to Pedestrians” sign (R10-15) to eliminate/reduce potential conflicts
between turning vehicles and pedestrians.
Enhancements:
Table 2 summarizes the proposed enhancements as they relate to intersection geometry and
operations.
Page 10
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Table 2. Proposed Geometric and Operations Enhancements
Proposed Enhancement
1.
2.
Comments
Included in Current Design
Remove obstructions on landscaped island located at
The existing island would be reconstructed as part
northeast corner of the intersection to improve sight
of the proposed design. No landscaping is
lines.
proposed on the island.
Not Included in Current Design
The current design proposes to widen, and
reconstruct, the Carlisle Road northbound
approach to provide an exclusive left-turn lane, 1
through lane, and a shared through/right-turn lane.
Reposition, and/or provide supplemental, traffic signal New overhead traffic signal indications would be
indications for the Carlisle Road northbound approach. provided for each of the approach lanes.
Designer to ensure visibility of signal indications.
Supplemental signal indication on left-hand side of
approach may be necessary.
3.
4.
5.
6.
7.
Evaluate the feasibility of relocating, limiting, and/or
reconfiguring, the curbs cuts providing access to the
Gulf gas station along Boston Road to provide a larger
separation between the driveways and the Littleton
Road westbound right-turn lane.
Designer to review.
Property owners have been involved in the 25%
design process and will continue to be involved as
the design progresses.
Continue to work with adjacent property owners on access management issues, including The ability to provide improved forced right-turn
limiting/improving driveway access and turn restrictions
islands at the gas station driveways may be limited
in an effort to reduce friction and improve overall
by differences in elevation and by the available
safety.
land area between the proposed roadway
alignment and the gas pumps; however, this issue
should be further evaluated.
Designer to review sight distance and advance
Consider sight distance limitations along Littleton Road
warning signage requirements for lane use and
eastbound.
traffic signals.
Evaluate Littleton Road eastbound double left-turns
and the Boston Road southbound double left-turns to
ensure that the receiving lanes are wide enough to
Designer to review for best practice.
accommodate heavy vehicles and to prevent
sideswipes.
Evaluate heavy vehicle turning radii and receiving lane
requirements for proposed third left-turn lane on the
Designer to review.
Littleton Road eastbound approach at Boston Road/Carlisle Road if it is approved. Page 11
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Proposed Enhancement
8.
Evaluate weaving between the intersection and the I495 ramps and consider how the addition of the third
Littleton Road eastbound left-turn lane would function
and how this 600 foot section along Boston Road
would be signed to provide guidance.
9.
Evaluate skew in the proposed alignment of Boston
Road in the northbound direction between
approximately Station 106 and Station 108. Consider
ways to increase taper length and/or adjust alignment
to provide a smoother transition.
10. Consider the appropriateness of either prohibiting
Littleton Road westbound U-turns, that will occur during
the proposed protected left-turn phase, or adding a
“Turning Traffic Must Yield to Pedestrians” sign (R1015) to eliminate/reduce potential conflicts between
turning vehicles and pedestrians.
Other
11. Continue to evaluate access management along the
Route 110 and Boston Road corridors as part of future
planning efforts and as adjacent properties are
developed/redeveloped. Consolidation of the number of
curb cuts will reduce friction and contribute toward
improving overall safety.
Comments
Designer to review.
Designer to review.
Designer to review.
Town of Westford to consider/evaluate over longterm.
Page 12
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Safety Issue #2. Signage and Pavement Markings
Observations:
The RSA team noted the following observations with regards to existing signage and pavement
markings at, or in the vicinity of, the intersection.
General Observations
The RSA team noted that several of the
guide and regulatory signs at the intersection
are in poor condition, including damaged or
faded signage and twisted/bent sign posts,
making them difficult for motorists to read
as they drive through the intersection.
RSA team members noted that pavement
markings are generally in poor condition.
Damaged guide sign.
Sign Placement
The RSA team noted that the visibility of the following signs was limited due to the presence of
trees, utility poles, and other obstructions:

Along the Littleton Road eastbound
approach, advance guide signage for
Route 225 is located behind a utility
pole;

Along the Littleton Road eastbound
approach, advance guide signage for
I-495/Boston Road is partially
located behind a tree;

On the Carlisle Road northbound
approach, visibility of guide signage
for Route 110 is partially blocked
by guide signage for I-495; and

Visibility of guide signage along Carlisle Road
northbound is limited due to overgrown vegetation.
On the Carlisle Road northbound
approach, advance guide signage for Route 495 (located approximately 300 feet south of
Littleton Road) is partially blocked by overgrown vegetation.
Page 13
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Sign Clutter
RSA team members noted that there was some non-essential signage (e.g., private advertising
signage) along the Carlisle Road northbound and Boston Road southbound approaches that added
to sign clutter at the intersection.
Guide Signage
RSA team members noted that the Carlisle Road
street sign mounted a utility pole on the
southwest corner of the intersection is placed at a
location approximately 30 feet south of the
intersection making it difficult for motorists
traveling along Littleton Road to see the sign.
South of intersection along Melissa Drive, RSA
team members noted several unconventional
signs in residential driveways asking motorists
not to turn around in their driveway (e.g. “please
no turns”). Such signage may indicate driver
confusion due to inadequate guide signage.
Unconventional signage on Melissa Drive.
Page 14
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Enhancements:
Table 3 summarizes the proposed enhancements with respect to signage.
Table 3. Proposed Signage and Pavement Marking Enhancements
Proposed Enhancement
1.
2.
3.
4.
5.
6.
Comments
Included in Current Design
Repair/replace signage and sign posts currently in poor
Included in design.
condition, as appropriate.
Re-stripe and maintain durable pavement markings at
Included in design.
the intersection
Not Included in Current Design
Review all way-finding signage for clarity and replace
Designer to review.
as appropriate.
Town of Westford should trim overgrown
Improve visibility of signage that is currently blocked
vegetation in the short-term.
from full view by overgrown vegetation and other
obstructions, as appropriate.
Designer to review all sign placement as part of
design process.
Relocate Carlisle Road street sign closer to the
Designer to review.
intersection to improve visibility for motorists traveling
along Littleton Road.
Other
Town of Westford should remove unauthorized
Remove non-essential signage to reduce sign clutter.
private advertising signage, and other nonessential signage, as appropriate.
Page 15
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Safety Issue #3. Pedestrian Accommodations
Observations:
Pedestrian sidewalks are generally provided along the northeast, southeast, and southwest corners
of the intersection; however, they have limited connectivity to adjacent uses. For example, a
pedestrian sidewalk is provided along Boston Road and Littleton Road adjacent to the Gulf gas
station on the northeast corner of the intersection, but there is no connection to the commercial
uses to the east along Littleton Road. No sidewalks are provided along the northwest corner of
the intersection and no crosswalks are provided at the intersection.
During the RSA, observed pedestrian activity was very light. According to the crash records, no
pedestrian related crashes were reported at the intersection between September 2008 and October
2010.
An RSA team member noted a pedestrian desire line along the west side of Carlisle Road between the residential neighborhood near Liberty
Way and the edge of the Rite Aid property located along the southwest corner of the intersection. RSA team members noted that pedestrian sidewalks leading to the intersection at the northeast and southeast corners suggest a pedestrian crossing across the eastern leg of Littleton Road; however, no crosswalk is provided. Sidewalk to Littleton Road, but no crosswalk.
An RSA team member noted that disabled members of the community had requested that audible
pedestrian signals be installed as part of any improvements to the intersection.
During the RSA, team members noted that sidewalks were generally obstructed with snow.
Design-Specific Comments:
RSA team members noted that the current 25% redesign efforts include installing crosswalks
across the southern and eastern legs of the intersection. During the RSA, team members also
discussed the feasibility of providing pedestrian access to the northwest corner of the intersection.
The ability to add a pedestrian crosswalk to the northwest corner of the intersection is limited by
the vertical grade difference between the Mobil gas station parcel and the roadway and potential
impacts on signal phasing/operations. As part of the design process, the designer should continue
to explore alternatives to provide pedestrian access to the northwest corner of the intersection and
document impacts to intersection operations so that an informed decision can be made.
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Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Enhancements:
Table 4 summarizes the proposed pedestrian accommodation enhancements.
Table 4. Proposed Pedestrian Enhancements
Proposed Enhancement
1.
2.
3.
4.
5.
Comments
Included in Current Design
Current design proposes to add crosswalks across
Install pedestrian crosswalks across the intersection.
the southern and eastern legs of the intersection
Not Included in Current Design
Continue to explore alternatives to provide pedestrian
access to the northwest corner of the intersection and
Designer to evaluate.
document impacts to intersection operations so that an
informed decision can be made.
Consider installing audible pedestrian signals as part of
Designer to evaluate.
proposed intersection improvements.
Other
Work with adjacent land owners to improve snow
Town of Westford
clearing from sidewalks and wheelchair ramps.
Continue to evaluate improvements to pedestrian
connections along Littleton Road, Boston Road, and
Town of Westford should consider these
Carlisle Road as part of future planning efforts and as
improvements in the long-term.
adjacent properties are developed/redeveloped.
Page 17
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Safety Issue #4. Bicycle Accommodations
Observations:
No bicycle provisions are provided at the intersection with the exception of share the road
signage posted along Carlisle Road southbound and Boston Road northbound.
Enhancements:
Provide bicycle accommodations within the study area (i.e., shared lanes and/or within a 4-foot
shoulder, bicycle detection at signals, signage, and pavement markings) in accordance with the
2006 Project Development and Design Guide, as appropriate.
The current design proposes to provide a 4 foot shoulder to accommodate bicycles.
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Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Potential Safety Enhancements
Based on its observations and discussions, the RSA team identified the issues and possible enhancements
that could improve safety the intersection of Littleton Road (Route 110)/Boston Road/Carlisle Road
(“Minot’s Corner”) in Westford, Massachusetts. Many of the enhancements identified during the RSA
have already been evaluated as part of the design process, although further design work or consideration
may be necessary to determine the feasibility of making some of the improvements to the intersection.
Short-term enhancements include:

Reduce sign clutter;

Improve visibility of existing signage; and

Work with land owners to improve snow removal along sidewalks.
To enhance the safety of the intersection, the long-term enhancements are to:

Improve visibility of traffic signal indications;

Improve signage;

Improve pavement and lane use markings;

Improve pedestrian accommodations; and

Improve bicycle accommodations.
Table 5 summarizes these safety issues, possible enhancements, estimated safety payoff, time frame, cost,
and responsibility. Safety payoff estimates are based on engineering judgment and are categorized as
low, medium, and high. The time frame is categorized as short-term (<1 year), mid-term (1 to 3 years), or
long-term (typically >3 years). Long-term improvements are typically considered to be substantial
improvements with an expected time frame for implementation greater than 3 years; however, if
improvements to the study area are selected as an HSIP project, then redesign of the intersection would be
advertised for construction sooner. The costs are categorized as low (<$10,000), medium ($10,001 to
$50,000), or high (>$50,000).
It is the responsibility of the Town of Westford to ensure that the designer incorporates the relevant safety
enhancements identified as part of this RSA. The RSA is intended to identify potential safety
improvements that can be evaluated and included as part of the design process for the reconstruction. The
short-term low-cost potential improvements should be considered by the responsible agency for
implementation prior to reconstruction.
Page 19
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Table 5. Summary of Potential Safety Enhancements
Safety Issue
Safety Enhancement
Reposition, and/or provide supplemental, traffic signal
indications for the Carlisle Road northbound approach. Ensure
visibility of signal indications. Supplemental signal indication on
left-hand side of approach may be necessary
Remove obstructions on landscaped island located at northeast
corner of the intersection to improve sight lines.
Evaluate the feasibility of relocating, limiting, and/or
reconfiguring, the curbs cuts providing access to the Gulf gas
station along Boston Road to provide a larger separation
between the driveways and the Littleton Road westbound rightturn lane.
Continue to work with adjacent property owners on access
management issues, including limiting/improving driveway
Intersection Geometry access and turn restrictions in an effort to reduce friction and
improve overall safety.
Consider sight distance limitations along Littleton Road
eastbound. Designer to review sight distance and advance
warning signage requirements for lane use and traffic signals.
Continue to evaluate access management along the Route 110
and Boston Road corridors as part of future planning efforts and
as adjacent properties are developed/redeveloped.
Consolidation of the number of curb cuts will reduce friction and
contribute towards improving overall safety.
Evaluate Littleton Road eastbound double left-turns and the
Boston Road southbound double left-turns to ensure that the
receiving lanes are wide enough to accommodate heavy
vehicles and to prevent sideswipes.
Safety
Payoff
Time
Frame
High
Cost
Responsibility1
Status2
Longterm
Mid
-
Needs further
evaluation in
next submittal
Medium
Longterm
Low
-
Included in
design
Low
Longterm
Mid
Designer
Needs further
evaluation in
next submittal
Medium
Longterm
High
Town/Designer
On-going
Low
Longterm
Low
Designer
Need further
evaluation in
next submittal
Medium
Longterm
Low
Town of Westford
For on-going
consideration
Medium
Longterm
Low
Designer
Needs further
evaluation in
next submittal
Notes:
1. It is the responsibility of the Town of Westford to ensure that the designer incorporates the relevant safety enhancements identified as part of this RSA.
2. The designer shall ensure that all enhancements listed as “Included in Design” are designed per current MassDOT standards, as appropriate.
Page 20
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Safety Issue
Time
Frame
Medium
Responsibility1
Status2
Longterm
Low
Designer
Needs further
evaluation in
next submittal
Medium
Longterm
Medium
Designer
Needs further
evaluation in
next submittal
Medium
Longterm
Low
Designer
Needs further
evaluation in
next submittal
Medium
Longterm
Low
Designer
Needs further
evaluation in
next submittal
Low
Longterm
Low
-
Included in
design
Low
Longterm
Low
-
Review all way-finding signage for clarity and replace as
appropriate.
Low
Longterm
Medium
-
Relocate Carlisle Road street sign closer to the intersection to
improve visibility for motorists traveling along Littleton Road.
Low
Longterm
Low
-
Evaluate weaving between the intersection and the I-495 ramps
and consider how the addition of the third Littleton Road
eastbound left-turn lane would function and how this 600 foot
section along Boston Road would be signed to provide
guidance.
Evaluate skew in the proposed alignment of Boston Road in the
northbound direction between approximately Station 106 and
Station 108. Consider ways to increase taper length and/or
Intersection Geometry adjust alignment to provide a smoother transition.
(continued)
Evaluate heavy vehicle turning radii and receiving lane
requirements for proposed third left-turn lane, if approved, at
the Littleton Road eastbound approach at Boston Road/Carlisle
Road.
Consider the appropriateness of either prohibiting Littleton
Road westbound U-turns, that will occur during the proposed
protected left-turn phase, or adding a “Turning Traffic Must
Yield to Pedestrians” sign (R10-15) to eliminate/reduce
potential conflicts between turning vehicles and pedestrians.
Repair/replace signage and sign posts currently in poor
condition, as appropriate.
Re-stripe and maintain durable pavement markings at the
intersection
Signage and
Pavement Markings
Safety
Payoff
Cost
Safety Enhancement
Included in
design
Needs further
evaluation in
next submittal
Needs further
evaluation in
next submittal
Notes:
1. It is the responsibility of the Town of Westford to ensure that the designer incorporates the relevant safety enhancements identified as part of this RSA.
2. The designer shall ensure that all enhancements listed as “Included in Design” are designed per current MassDOT standards, as appropriate.
Page 21
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Safety Issue
Signage and
Pavement Markings
(continued)
Safety Enhancement
Improve visibility of signage that is currently blocked from full
view by overgrown vegetation and other obstructions, as
appropriate.
Low
Shortterm
Cost
Responsibility1
Status2
For
Town of Westford immediate
consideration
Low
Needs further
evaluation in
next submittal
For
Low
Town of Westford immediate
consideration
Included in
Medium
design
Low
Shortterm
Medium
Longterm
Continue to explore alternatives to provide pedestrian access to
the northwest corner of the intersection and document impacts
Medium
to intersection operations so that an informed decision can be
made.
Longterm
Medium
Consider installing audible pedestrian signals as part of
proposed intersection improvements.
Medium
Longterm
Medium
Low
Shortterm
Low
Longterm
Low
Town of Westford
For long-term
consideration
Longterm
Low
-
Included in
design
Install pedestrian crosswalks across the intersection.
Work with adjacent land owners to improve snow clearing from
sidewalks and wheelchair ramps.
Bicycle
Accommodations
Time
Frame
Designer
Remove unauthorized private advertising signage, and other
non-essential signage, as appropriate to reduce sign clutter.
Pedestrian
Accommodations
Safety
Payoff
Continue to evaluate improvements to pedestrian connections
along Littleton Road, Boston Road, and Carlisle Road as part of
Medium
future planning efforts and as adjacent properties are
developed/redeveloped.
Provide bicycle accommodations within study area (i.e., shared
lanes and/or within a 4-ft shoulder, bicycle detection at signals,
Medium
signage, and pavement markings) in accordance with the 2006
Project Development and Design Guide, as appropriate.
Designer
Needs further
evaluation in
next submittal
Needs further
evaluation in
next submittal
For shortTown of Westford
term
consideration
Designer
Notes:
1. It is the responsibility of the Town of Westford to ensure that the designer incorporates the relevant safety enhancements identified as part of this RSA.
2. The designer shall ensure that all enhancements listed as “Included in Design” are designed per current MassDOT standards, as appropriate.
Page 22
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Appendix A. 25% Design Plans Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Appendix B. RSA Meeting Agenda Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Appendix C. RSA Audit Team Contact List Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Participating Audit Team Members
Date:
Monday, January 10, 2011
Location: Westford Town Hall, 55 Main Street, Westford, MA
Audit Team Members
Agency/Affiliation
E-mail Address
Phone Number
Paul Starratt
Town of Westford, Town Engineer
pstarratt@westfordma.gov
(978) 399-2716
Fred Palmer
Town of Westford Planning Board
palmerfr@aol.com
(978) 692-7531
Jeremy Downs
Town of Westford
jdowns@westfordma.gov
(978) 399-2721
Michael Croteau
Town of Westford Police Department
mcroteau@westfordma.gov
(978) 399-2052
Northern Middlesex Council of Governments
Justin Howard
JHoward@nmcog.org
(978) 454-8021
(NMCOG)
Northern Middlesex Council of Governments
Sarah Bradbury
SBradbury@nmcog.org
(978) 454-8021
(NMCOG)
Northern Middlesex Council of Governments
David Tilton
DTilton@nmcog.org
(978) 454-8021
(NMCOG)
Alan Cloutier
Fay, Spofford & Thorndike
acloutier@fstinc.com
(781) 221-1000
Michelle Daigle
Federal Highway Administration
michelle.daigle@dot.gov
(617) 494-3330
Joshua Grzegorzewski
Federal Highway Administration
joshua.grzegorzewski@dot.gov
(617) 494-2791
Azad Kidher
MassDOT – Project Management
Azad.Kidher@state.ma.us
(617) 973-7361
Chris Hogan
MassDOT
christopher.hogan@state.ma.us
(508) 929-3915
Llaneza, Lou (DOT)
MassDOT
Lou.Llaneza@state.ma.us
(508) 341-6941
Bonnie Polin
MassDOT Highway Division Safety Section
bonnie.polin@state.ma.us
(617) 973-7991
Lisa Schletzbaum
MassDOT Highway Division Safety Section
lisa.schletzbaum@state.ma.us
(617) 973-7685
Keri Pyke
Howard/Stein-Hudson Associates
kpyke@hshassoc.com
(617) 482-7080
Joe SanClemente
Howard/Stein-Hudson Associates
js@hshassoc.com
(617) 482-7080
Alexandra Siu
Howard/Stein-Hudson Associates
asiu@hshassoc.com
(617) 482-7080
Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Appendix D. Detailed Crash Data Road Safety Audit
Minot’s Corner, Westford
Prepared by Howard/Stein-Hudson Associates, Inc.
Appendix E. Additional Information