ROAD SAFETY AUDIT
Route 2/Taylor Road/Piper Road
Town of Acton
March 4, 2015
Prepared For:
Massachusetts Department of Transportation
Prepared By:
Tetra Tech, Inc.
One Grant Street
Framingham, MA 01702
Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Table of Contents
Background ................................................................................................................................. 1
Project Data ................................................................................................................................. 1
Project Location and Description .............................................................................................. 2
Audit Observations and Potential Safety Enhancements........................................................ 4
Summary of Road Safety Audit ............................................................................................... 15
List of Appendices
Appendix A.
Appendix B.
Appendix C.
Appendix D.
RSA Meeting Agenda
RSA Audit Team Contact List
Traffic and Crash Data
RSA References
List of Figures
Figure 1.
Locus Map .............................................................................................................................. 3
List of Tables
Table 1.
Table 2.
Participating Audit Team Members ....................................................................................... 2
Potential Safety Enhancement Summary ............................................................................. 16
Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Background
The MassDOT Highway Division obtains crash data from the Massachusetts Registry of Motor Vehicles
(RMV) database and uses the data for many purposes. One of the primary purposes is to identify high
crash locations at intersections throughout the Commonwealth. The crashes are grouped into clusters
based on a crash cluster analysis method developed by their consultant, Geonetics. The information is
presented in a GIS format which merges the crashes into clusters based on their location relative to each
other. The software then calculates an Equivalent Property Damage Only (EPDO) rating for all the
clusters and ranks them. Based on this analysis methodology the intersection of Route 2, Taylor Road and
Piper Road in the Town of Acton has been identified as a high crash location experiencing a total of 39
crashes (2010-2012) with an EPDO rating of 93. It is also on the Top 200 High Crash Intersection Report.
A Road Safety Audit was conducted at this location approximately nine years ago on September 29, 2006.
At that time safety issues identified were related to travel speed, traffic signal equipment, cluttered
signing, drainage at the southwest corner, over grown vegetation and a lack of pedestrian
accommodations. Several of the audit’s recommendations were implemented including installation of
illuminated signal ahead warning signs on Route 2, drainage improvements in the southwest corner of the
intersection, updated pavement markings and installation of a YIELD sign at the eastbound right turn.
The Road Safety Audit (RSA) process is a way of evaluating the safety of an intersection using a
multidisciplinary team of engineers, administrators and safety personnel to identify issues that may be
corrected to improve safety. The Team may identify short-term, medium-term, and long-term
improvements which can be implemented by the local jurisdiction, or MassDOT, through their normal
maintenance process or a design/construction process.
Project Data
The audit was conducted on Wednesday, March 4, 2015. The RSA agenda appears in Appendix A. Table
1 lists the audit team participants and their affiliation. The contact information for the audit team
members is contained in Appendix B.
Data reviewed at the RSA included area maps, peak hour traffic volumes, speed limit regulations and
detailed crash information and is contained in Appendix C. A brief summary of this data is provided
below.
Traffic Volumes
•
Traffic volume counts obtained on November 19, 2014 indicate that Route 2 carries
approximately 3,600 vehicles during peak hours of traffic.
•
Assuming approximately 10 percent of Route 2 traffic occurs during peak hours, the daily volume
on Route 2 is estimated at approximately 36,000 vehicles per day.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Table 1. Participating Audit Team Members
Audit Team Member
Agency/Affiliation
Kevin Chiang
MassDOT Safety
Alolade Campbell
MassDOT District 3 Traffic
Chenyuan Wang
Central Transportation Planning Staff
Michael Cook
State Police – Concord
Chris Prehl
Town of Acton Police Department
James Cogan
Town of Acton Police Department
Robert Hart
Town of Acton Fire Department
Patrick Futterer
Town of Acton Fire Department
Corey York
Town of Acton Engineering Department
Robert Waite
Town of Acton Highway Department
Kevin Farrell
Town of Acton Highway Department
Nancy Doherty
Tetra tech
James Antonizick
Tetra Tech
Crash Data
•
39 total crashes occurred over the 3 year period (2009-2011).
•
29 of the 39 crashes involved a vehicle traveling westbound on Route 2.
•
The most prevalent crash types are angle (46%) and rear-end (38%).
•
Approximately two-thirds of the crashes involved injuries.
•
The most common angle collision involved vehicles traveling on Route 2 westbound and Taylor
Road southbound. Vehicles on Route 2 were typically at fault and were cited with Disregarding
Traffic Signs, Signals and Markings.
•
Local police officials indicated that the most serious collisions involved vehicles traveling on
Piper Road and westbound Route 2.
Project Location and Description
The Route 2/Taylor Road/Piper Road signalized intersection, shown on Figure 1, is located in Acton, 2.25
miles west of the Concord Rotary (Route 2/Route 2A/Barretts Mill Road/Commonwealth Avenue) and
800 feet east of the Route 2/Route 111 interchange.
This is the only at-grade signalized crossing of Route 2 in Acton. The next signalized intersection on
Route 2 is located approximately 20 miles to the west in Fitchburg.
Route 2 is a principal arterial traveling between Boston and the Massachusetts/New York state border. In
the vicinity of its intersection with Taylor Road/Piper Road, Route 2 provides two travel lanes in each
direction, a wide median and has a posted speed limit of 45 mph. Both Route 2 approaches widen to
provide channelized left turn lanes.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
The Route 2 eastbound channelized right turn lane at Piper Road is under YIELD sign control. The Route
2 westbound channelized right turn onto Taylor Road is under YIELD sign control, although the YIELD
sign is missing.
Taylor Road and Piper Road are Rural Minor Collectors under local jurisdiction. Each provides one travel
lane per direction and has a posted speed limit of 25 mph. Piper Road widens as it approaches Route 2 to
provide a channelized right turn lane under YIELD sign control with a partial acceleration lane for
vehicles turning onto Route 2.
Geometrically, the wide median creates two intersections: Route 2 westbound/Taylor Road and Route 2
eastbound/Piper Road. However, the two intersections operate together with a single traffic signal
controller. The controller operates with an EB/WB through phase, then protected left turn phasing for
Route 2 and permissive left turn phasing for the Piper Road and Taylor Road approaches.
Figure 1.
Locus Map
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Audit Observations and Potential Safety
Enhancements
The RSA was conducted at Acton Town Hall. Due to weather conditions, a site visit was not possible.
However, based on photographs of the site and the high level of familiarity of most team members with
the intersection, the team was able to identify safety issues and potential safety enhancements. The
following safety issues were identified:
1. Route 2 Vehicle Speeds
2. Intersection Geometry
3. Poor Sight Lines
4. Traffic Signal Operations
5. Intersection Signs and Pavement Markings
6. Pedestrian Facilities
7. Bicycle Accommodations
8. Route 111 Junction
The following section describes each of these issues in more detail and discusses the potential
enhancements and safety improvements developed by the RSA team. Following this section is a summary
table outlining the issue, the potential solution, timeframe and responsible agency.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #1 – Route 2 Vehicle Speeds
Observations:
1. RSA audit members indicated that vehicles traveling west on Route 2 travel at high rates of
speed. Officers Cook and Prehl indicate that travel speeds exceeding 60 mph in the 45 mph zone
are quite typical.
2. In Concord, the segment of Route 2 westbound, between the rotary and the Acton/Concord town
line, has a posted speed limit of 25 mph. At the town line the speed limit increases to 45 mph
(approximately 1.6 miles east of the intersection). Speed limit signs are posted on both sides of
westbound Route 2, approximately 600 feet in advance of the intersection. This sign may suggest
that free-flow conditions exist.
3. Police officials also indicated that speeding violations are frequently over turned in court by court
officials. When court officials are shown photographs of the Route 2 segment between the
Concord Rotary and Taylor Road/Piper Road by the defendant, court officials appear to feel that
travel speeds exceeding 45 mph are appropriate and rule against the issuing police officer.
4. It was noted in the 2006 Road Safety Audit that the 85th percentile speed (measured in 2003) was
61 mph.
Potential Safety Enhancements:
The RSA team provided numerous suggestions for enforcing the current speed limit on Route 2.
1. Install ‘reduced speed ahead’ signs if appropriate, and review existing speed signs.
2. Increase police enforcement of speed regulations.
3. Provide locations along the north side of Route 2 for police vehicles to park for enforcement.
4. Educate court officials regarding high crash rates at intersection and the importance of regulating
speed on Route 2.
5. Implement traffic calming measure where appropriate. Suggested calming measures included:
a. Consider installing transverse rumble strips on westbound Route 2, similar to those
installed at toll plazas.
b. Redesigning the intersection as a roundabout.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #2 – Intersection Geometry
Observations:
The wide center median, coupled with permissive
signal phasing for the Taylor Road/Piper Road
approaches encourages motorist to run the red light so
not to be caught in the median area.
Town officials mentioned that school buses are stored
at the Adesa site located on the south side of Route 2,
east of the intersection. When the school buses leave
the Conant School (located on Taylor Road, just north
of the intersection), they travel south on Taylor Road
and turn left onto Route 2 eastbound. Often the buses
are stacked within the median while waiting for a gap
in Piper Road northbound traffic in which to turn left.
Potential Safety Enhancements:
Several options for improving the intersection’s geometry were discussed. Options ranged from simple
imrovements to the existing geometry to reconfiguration of the entire intersection.
1. Redesign and reconstruct the signalized intersection. Review intersection geometry and the ability
to provide short dedicated left turn lanes on the center median roadway.
2. Several options for turn restrictions were discussed. In each case, the impact to location
roadways/town-wide circulation would need to be evaluated. Options discussed included:
a. Prohibit all left turns at the intersection. In effect, close the opening in the Route 2
median island.
b. Prohibit left turns from Route 2 onto Taylor Road/Piper Road.
c. Prohibit a left turn from Taylor Road onto Route 2.
3. As potential long term solutions consider:
a. Grade-separating the intersection and provide a single point diamond interchange.
b. Providing fly over ramps to accommodate vehicles turning left from the minor street
approaches onto Route 2.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #3 – Poor Sight Lines
Observations:
RSA participants reported that sight lines to the intersection
from the west are poor. There is a major horizontal curve
approaching the intersection. Also, the bridge abutments of the
Route 111 overpass restrict sight lines approaching the signal.
Within the median are a number of trees which obstruct sight
lines to the intersection.
Route 111
Potential Safety Enhancements:
It was suggested that tree removal in the median both before
and after the bridge would improve sight lines to the
intersection.
Route 2 EB Sight Line Obstructions
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #4 – Traffic Signal Operations
Observations:
1. The signal equipment is older and does not appear to meet MUTCD standards. Signal indications
are on mast arms and post mounted. The post mounted indications are difficult to see and are not
recommended for high speed approaches such as Route 2.
2. The intersection is heavily signed and the signs may be distracting the motorist’s eye from the
traffic signal indications. This is particularly problematic in the westbound direction.
3. The green diagrammatic guide sign for Exit 43 (Route 111
west), located just west of the intersection, is in the line of sight
of the signal head mounted on the mast arm. Additionally, the
blue Tourist Oriented Directional sign (Exit 43) located in
advance of the intersection, in the westbound direction, partially
obstructs the sight line to the signal indications.
4. Solar glare is a problem in the afternoon.
5. The signal indications facing the center median approaches are
visible to vehicles stopped on Piper and Taylor Road. The signal
head indications are either not optically programmable or are not
programed correctly.
Signal masked by guide sign
6. One of the signal heads facing the Piper Road through
lane has shifted and appears to be facing the
channelized right turn lane under YIELD sign control.
7. Yellow and red clearance intervals may not be
designed properly for the actual travel speeds on Route
2 (60+ mph). It was noted by police officials that long
yellow clearance intervals encourage speeding through
an intersection.
Piper Road signal head
8. A weave maneuver occurs when vehicles enter Route 2 westbound from Taylor Road and exit
within 900 feet onto the Route 111 off-ramp. As a right turn on red is permitted from Taylor
Road these vehicles are both accelerating into Route 2 traffic and weaving within 900 feet.
9. One third of collisions occurred at dusk or in the dark. The lack
of street lighting may be contributing to these collisions.
Potential Safety Enhancements:
1. Reconstruct the traffic control signal including mounting all
signals overhead on mast arms to improve visibility from all
directions, video bicycle detection and possibly adaptive signal
control technology.
2. To increase visibility and mitigate solar glare, install back plates
with yellow retroflective borders on signal heads facing Route 2.
Intersection at night - Looking west
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
3. Review and calculate proper signal clearance intervals. Proper clearance intervals (Yellow, Red)
take into account the intersection width and approach speeds allow for the safe passage of
vehicles during the change interval. Police officials suggested shorter yellow intervals with a
longer all-red interval.
4. Consider modifying the existing permissive phasing for the Taylor Road and Piper Road
approaches with split phasing.
5. Consider a ‘No Turn on Red’ restriction for southbound Taylor Road.
6. Install street lighting.
7. Consider dilemma zone detectors to mitigate red-light running.
8. Install optically programmable signal heads on the far side of the northbound and southbound
approaches within the center median roadway.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #5 – Intersection Signs and Pavement Markings
Observations:
1. The intersection has a cluttered appearance which detracts from
the traffic signal. This is attributed to both the existing signage
and signal equipment.
2. A variable message sign (STOPPED TRAFFIC AHEAD) is
located on Route 2 eastbound, approximately 1,500 feet west of
the intersection and in
advance of a horizontal
curve. The sign is activated
by a video detection camera Route 2: Looking East
located approximately 900
feet downstream from the sign. RSA participants indicated
that they have never seen the sign illuminated, raising the
question of whether the sign is malfunctioning or eastbound
vehicle queues are not long enough to be detected by the
video camera. According to signal plans provided by
Variable message sign
MassDOT, the detection zone for the variable message sign
covers a 200 foot segment of Route 2, approximately 600 to 800 feet from the intersection.
3. On the westbound approach a cantilever mounted signal ahead warning sign with wig-wag
flashing beacons is located approximately 1,200 feet east of the intersection. The flashing
beacons are not operational.
4. As noted in Safety Issue #4, the green diagrammatic guide sign for Exit 43 (Route 111 west) is in
the same line of sight as the signal head mounted on the mast arm facing Route 2. This sign may
deter westbound motorists from focusing on the traffic signal indication.
5. Also, as noted in Safety Issue #4, the blue Tourist Oriented Directional sign (Exit 43) located in
advance of the intersection in the westbound direction partially obstructs the sight line to the
intersection signals.
6. A YIELD sign is not present at the channelized right turn from westbound Route 2 onto Taylor
Road.
Potential Safety Enhancements:
1. Review all signs within the intersection for compliance with MUTCD. Remove superfluous signs.
2. Repair the wig-wag flashing beacon on the Route 2 westbound.
3. Replace the wig-wag flashing beacon with a variable message sign that indicates RED SIGNAL
AHEAD.
4. Verify the variable message sign on eastbound Route 2 is operational. Repair if necessary.
5. Re-evaluate the location of the variable message sign. Conduct queuing analysis during peak
hours, and review stopping sight distance.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
6. Consider moving the detection zone for the variable message sign closer to the intersection so it is
activated more frequently or alternatively, consider replacing the variable message sign with a
sign that indicates RED SIGNAL AHEAD based on the signal indications at the intersection in
the eastbound direction.
7. Consider relocating/redesigning the green Exit 43 diagrammatic sign to a location possibly east of
the intersection.
8. Relocate the Exit 43 Tourist Oriented Directional sign so not to obstruct sight lines to the
intersection.
9. Maintain Stop lines and pavement markings on all roadways.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #6 – Pedestrian Facilities
Observations:
Although no pedestrian crashes were reported at this intersection,
pedestrian accommodations are minimal. Bituminous sidewalk is
provided along the easterly side of Piper Road and along the south
side of Route 2, west of Piper Road. Local officials indicated that the
sidewalks are used at lunch time by occupants of an office park on
Piper Road to reach the Roche Bros plaza located on Route 111. The
sidewalks are in poor condition.
The intersection’s single crosswalk is located on Piper Road
approximately 50 feet south of the point where vehicles turning right
from Route 2 enter Piper Road. Warning signs or overhead lighting
are not provided at the crosswalk. The transition from the sidewalk to
the crosswalk does not meet current design standards for pedestrian
accommodations and ADA accessibility.
Piper Road Sidewalk
Town officials indicated that additional pedestrian accommodations
were not wanted for the intersection, but that the existing Piper Road
crosswalk should be enhanced to improve safety.
Potential Safety Enhancements:
Piper Road Crosswalk
1. Reconstruct the sidewalk and add ADA compliant accessible
ramps at the crosswalk.
2. Install advanced pedestrian warning signs on Piper Road and on the Route 2 eastbound
channelized right turn lane leading to the Piper Road crosswalk.
3. Install pedestrian crossing signs at the crosswalk.
4. Consider installation of pedestrian crossing signs with RRFBs (Rectangular Rapid Flash
Beacons) to increase awareness of the crosswalk area.
5. Consider illuminating the crosswalk.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #7 – Bicycle Accommodations
Observations:
There are no bicycle accommodations at the intersection. Town officials indicated that cyclists do use the
intersection to travel across Route 2. An officer mentioned that a bicyclist had a crash involving a catch
basin grate.
Potential Safety Enhancements:
1. Provide bicycle accommodation per MassDOT’s new Healthy Transportation Initiative Policy.
Enhancements may include wider shoulders or dedicated bike lanes on the Tayor Road and Piper
Road approaches as well as video bicycle detection and bike route signs & pavement markings
(shared lane markings, for example) to alert drivers to the presence of the bikeway.
2. Check all catch basins grates to ensure they are oriented properly so not to trap bicycle tires.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Safety Issue #8 – Route 111 Junction
Observations:
A weaving maneuver occurs on eastbound Route 2 between the Route
111 on-ramp merge and the intersection at Taylor Road/Piper Road.
Vehicles entering Route 2 from Route 111, intending to proceed north on
Taylor Road, must cross two travel lanes in approximately 700 feet. Town
officials indicate that this can be a difficult maneuver for motorists.
Team members also indicated that the merge from Route 111 onto Route
2 eastbound is difficult due to angle of the intersection and the lack of an
adequate acceleration lane.
Potential Safety Enhancements:
1. Illuminate the Route 111 merge by restoring the existing
overhead lighting fixtures.
Route 111 on-ramp and weaving segment
2. Consider replacing the existing YIELD sign with a STOP sign at the merge. (A STOP sign may
limit the ability of a merging vehicle to adequately accelerate onto Route 2.)
3. Enhance gore area pavement marking treatments.
4. Evaluate the existing acceleration lane and upgrade to current standards as required.
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Road Safety Audit—Route 2/Taylor Road/Piper Road
Prepared by Tetra Tech, Inc.
Summary of Road Safety Audit
Table 2 below summarizes the issues identified in the previous section and includes the potential safety
payoff, approximate cost, a time frame for completion and the responsible agency.
Safety payoff estimates are subjective and may be based on the relative percent of crashes that may be
reduced by the enhancement based on known and documented crash reduction factors, if available, or
estimated crash reduction based on a stated source [for example, low (<30%), medium (31% to 70%), and
high (>71%)]. The time frame is categorized as short-term (<1 year), mid-term (1 to 3 years), or longterm (>3 years). The costs are categorized as low (<$10,000), medium ($10,001 to $50,000), or high
(>$50,001).
Page 15
Table 2. Potential Safety Enhancement Summary
Safety Issue
1. Route 2 Vehicle
Speeds
Potential Safety Enhancement
Safety Payoff
Time Frame
Cost
Responsible Agency
Install ‘reduced speed ahead’ signs,
if appropriate and review all existing
speed signs.
Medium
Short-term
Low
MassDOT
Increase police enforcement of
speed regulations.
Medium
Short-term
Low
Acton and State Police
Provide locations along the north
side of Route 2 for police vehicles
to park for enforcement.
Medium
Medium-term
High
MassDOT
Educate court officials on the
importance of regulating speed on
Route 2.
Low
Short-term
Low
Acton and State Police
Medium
Medium-term
Medium
MassDOT
Consider replacing signal control
with a roundabout.
Low
Long-term
High
MassDOT
Redesign and reconstruct the
signalized intersection. Review
intersection geometry and the ability
to provide short dedicated left turn
lanes on the center median
roadway.
High
Long-term
High
MassDOT
Prohibit all left turns at the
intersection. In effect, close the
opening in the Route 2 median
island.
High
Medium-term
Medium
MassDOT
Prohibit left turns from Route 2 onto
Taylor Road/Piper Road.
Low
Medium-term
Medium
MassDOT
Consider installing transverse
rumble strips on westbound Route 2
to alert drivers approaching the
intersection.
2. Intersection
Geometry
Safety Issue
2. Intersection
Geometry (cont.)
3. Poor Sight Lines
4. Traffic Signal
Operations
Potential Safety Enhancement
Safety Payoff
Time Frame
Cost
Responsible Agency
Prohibit left turns from Taylor Road.
High
Medium-term
Medium
MassDOT
Grade-separate the intersection and
provide a single point diamond
interchange.
High
Long-term
High
MassDOT
Provide fly over ramps to
accommodate vehicles turning left
from the minor street approaches
onto Route 2.
High
Long-term
High
MassDOT
Remove trees in Route 2 median,
west of intersection.
Low
Short-term
Medium
MassDOT
Reconstruct the traffic control
signal, including mounting all
signals overhead on mast arms to
improve visibility from all directions,
video bicycle detection and possibly
adaptive signal control technology.
High
Long-term
High
MassDOT
Install back plates with yellow
retroflective borders on signal
heads facing Route 2.
High
Short-term
High
MassDOT
Medium
Short-term
Low
MassDOT
High
Short-term
Medium
MassDOT
Consider a ‘No Turn on Red’
restriction for right turns for
southbound Taylor Road.
Medium
Short-term
Low
MassDOT
Install street lighting.
Medium
Long-term
High
MassDOT/
Town of Acton
Review and calculate proper signal
clearance intervals.
Replace the existing permissive
phasing for the Taylor Road and
Piper Road approaches with split
phasing.
Safety Issue
4. Traffic Signal
Operations
(cont.)
5. Intersection
Signs and
Pavement
Markings
Potential Safety Enhancement
Safety Payoff
Time Frame
Cost
Responsible Agency
Consider dilemma zone detectors on
Route 2
Medium
Medium-term
High
MassDOT
Install optically programmable signal
heads on the far side of the
northbound and southbound
approaches within the median
roadway.
Medium
Medium-term
Medium
MassDOT
Review all signs in intersection for
compliance with MUTCD. Remove
superfluous signs.
Medium
Short-term
Low
MassDOT
Repair the wig-wag flashing beacon
on the Route 2 westbound.
Low
Short-term
Low
MassDOT
Replace the wig-way flashing
beacons with a variable message
sign that indicates RED SIGNAL
AHEAD.
Medium
Medium-term
High
MassDOT
Verify that the variable message
sign on eastbound Route 2 is
operational. Repair if necessary.
Low
Short-term
Low
MassDOT
Reevaluate the location of the
variable message sign. Conduct
queuing analysis during peak hours
and review stopping sight distance.
Medium
Medium-term
Low
MassDOT
Move the detection zone for the
variable message sign closer to the
intersection so it is activated more
frequently.
Low
Short-term
Low
MassDOT
Replace the Variable Message Sign
with one that indicates RED SIGNAL
AHEAD.
Medium
Short-term
Medium
MassDOT
Medium
Medium-term
High
MassDOT
Consider relocating/redesigning the
green Exit 43 diagrammatic sign to a
location possibly east of the
intersection.
Safety Issue
Potential Safety Enhancement
Safety Payoff
Time Frame
Cost
Responsible Agency
Medium
Medium-term
Medium
MassDOT
Low
Short-term
Low
MassDOT
Reconstruct the sidewalk and add
accessible ramps.
Medium
Long-term
High
MassDOT
Install pedestrian advanced warning
signs on Piper Road and on the
Route 2 eastbound channelized right
turn lane leading to the Piper Road
crosswalk.
Medium
Short-term
Low
MassDOT/
Town of Acton
Install RRFBs (Rectangular Rapid
Flash Beacons) to increase
awareness of the crosswalk area.
Medium
Medium-term
Medium
Town of Acton
Low
Medium-term
Medium
Town of Acton
High
Medium-term
High
MassDOT/
Town of Acton/
Check all catch basins grates to
ensure they are oriented properly so
not to trap bicycle tires.
High
Short-term
Low
MassDOT/
Town of Acton/
Illuminate the Route 111 merge area
by restoring the existing overhead
lighting fixtures
Medium
Short-term
Medium
MassDOT
Low
Medium-term
Low
MassDOT
Medium
Long-term
Medium
MassDOT
Relocate the Tourist Oriented
5. Intersection Signs Directional sign (Exit 43) so not to
obstruct sight lines to the intersection.
and Pavement
Markings (Cont.)
Maintain Stop lines and pavement
markings on all roadways.
6. Pedestrian
Facilities
Illuminate the crosswalk.
Provide bicycle accommodation
such as wider shoulders or
dedicated bike lanes on the Taylor
Road and Piper Road as well as
7. Bicycle
video bicycle detection and bike
Accommodations route signs & pavement markings.
8. Route 111
Junction
Enhance gore area pavement
marking treatments.
Evaluate the existing acceleration
lane and upgrade to current
standards as required.
Appendix A. RSA Meeting Agenda
Road Safety Audit
For the Intersection of:
Route 2/Piper Road/Taylor Road
Meeting Location: Acton Town Hall, Room 204
472 Main St., Acton, MA 01720
Wednesday, March 4, 2015
10:00 AM – 12:15 PM
Type of meeting:
High Crash Location – Road Safety Audit
Attendees:
Invited Participants to Comprise a Multidisciplinary Team
Please bring:
Thoughts and Enthusiasm!!
10:00 AM
Welcome and Introductions
 Meet at Town Hall
10:10 AM
Review of Site Specific Material
 Crash, Speed & Volume Summaries– provided in advance
 Existing Geometries and Conditions
10:40 AM
Visit the Site (Weather permitting)
 Drive to Intersection of Route 2/Piper Rd./Taylor Rd.(bring vest, hardhat, etc.)
 Park at 45 Discovery Way
 As a group, identify areas for improvement
11:30 AM
Post Visit Discussion / Completion of RSA
 Meet back at Town Hall
 Discuss observations and finalize findings
 Discuss potential improvements and finalize recommendations
12:15 PM
Adjourn
Instructions for Participants:
 Before attending the RSA, participants are encouraged to drive through the
intersection and complete/consider elements on the RSA Prompt List with a focus
on safety.
 All participants will be actively involved in the process throughout. Participants
are encouraged to come with thoughts and ideas, but are reminded that the
synergy that develops and respect for others’ opinions are key elements to the
success of the overall RSA process.
 After the RSA meeting, participants will be asked to comment and respond to the
document materials to assure it is reflective of the RSA completed by the
multidisciplinary team.
Appendix B. RSA Audit Team Contact List
Audit Team Member Agency/Affiliation
E-mail
Phone
Kevin Chiang
MassDOT Safety
Kevin.chaing@state.ma.us
978-368-9626
Alolade Campbell
MassDOT District 3 Traffic
Alolade.Campbell@state.ma.us
508-929-3887
Chenyuan Wang
Central Transportation Planning Staff
cyw@ctps.org
857-702-3698
Michael Cook
State Police – Concord
michael.cook@pol.state.ma.us
978-929-4100
Chris Prehl
Town of Acton Police Department
cprehl@acton-ma.gov
978-929-7530
James Cogan
Town of Acton Police Department
jcogan@acton-ma.gov
978-929-7518
Robert Hart
Town of Acton Fire Department
rhart@acton-ma.gov
978-844-6721
Patrick Futterer
Town of Acton Fire Department
pfutterer@acton-ma.gov
978-844-7042
Corey York
Town of Acton Engineering Department
cyork@acton-ma.gov
978-929-7740
Robert Waite
Town of Acton Highway Department
rwaite@acton-ma.gov
978-929-7641
Kevin Farrell
Town of Acton Highway Department
kfarrell@acton-ma.gov
978-621-9093
Nancy Doherty
Tetra Tech
nancy.doherty@tetratech.com
508-903-2008
James Antonizick
Tetra Tech
Jantonizick@tetratech.com
978-903-2406
Appendix C. Detailed Traffic & Crash Data
P:/4522114001 /Assign No 8 RSA Acton/SupportDocs/Graphics/Existing 2014 Peak Hour Traffic Volumes
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Framingham, MA 01701-9005
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Midday Peak Hour (2:00PM)
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Afternoon Peak Hour (4:00PM)
Road Safety Audit Rte. 2/Rte. 111 &Taylor Rd./Piper Rd.
Acton, Massachusetts
Not To Scale
Acton 11 /19/2014 TMC
Existing 2014 Peak Hour
Traffic Volumes
Acton, MA
Massachusetts Avenue (Rt2/Rt 111) and Taylor Road/Piper Road
TIME PERIOD ANALYZED: 1/1/2009 - 12/31/2011
6
Taylor Road
SOURCE OF CRASH REPORTS: Acton Police Department
34
Massachusetts Avenue (Rt 2/Rt 111 Westbound)
19
14
2 5 10
15 17
4
30
8 12 20
23 24 27 29
3
28 31
13
16
32
36
37
35
11
21
22
9
26
33
1
18
25
7
39
Piper Road
Massachusetts Avenue (Rt 2/Rt 111 Eastbound)
38
Crash Data Summary Table
Massachusetts Avenue(Route 2/Route 111) at Taylor Road/Piper Road, Acton, MA
January 1, 2009 to December 31, 2011
Crash
No.
Crash Date
Crash Day
Crash Time
Manner of
Collision
Ambient
Light
Weather
Condition
Road
Surface
Condition
Driver Contributing
Code
Age
(D1)
Age
(D2)
1
20-Feb-2009
Friday
6:45 AM
Rear-end
Daylight
Clear
Dry
Not Reported
28
31
2
30-Apr-2009
Thursday
9:25 PM
Angle
Dark - lighted
roadway
Not Reported
Dry
Not Reported
50
18
3
20-May-2009
Wednesday
3:45 PM
Rear-end
Daylight
Clear
Dry
Not Reported
29
29
4
23-Jun-2009
Tuesday
10:21 PM
Angle
Dark - lighted
roadway
Rain
Wet
Not Reported
22
28
5
26-Aug-2009
Wednesday
2:06 PM
Angle
Daylight
Clear
Dry
Not Reported
23
46
6
29-Aug-2009
Saturday
2:20 AM
Single vehicle
crash
Dark ­
roadway not
lighted
Rain
Wet
Not Reported
20
7
09-Oct-2009
Friday
6:32 PM
Rear-end
Dark - lighted
roadway
Rain
Wet
Not Reported
53
58
8
29-Dec-2009
Tuesday
12:31 PM
Angle
Daylight
Clear
Dry
20
Unknown
Not reported
Dark ­
roadway not
lighted
Age
(D3)
Comments
Veh 1 slowed down due to solar glare and upcoming traffic light. Veh 2 rear-ended Veh 1.
Veh 2 was looking down to the floor, did not notice the red light ahead and ran the red light when he hit Veh 1.
Operator 2 cited for failure to stop at a red light.
Veh 1 slowed down and Veh 2 rear ended Veh 1. Operator 2 got a written warning for failure to use care in
stopping.
Veh 1, traveling on Rte. 2 WB ran the red light hitting Veh 2, which was passing through the intersection.
Operator 1 cited for failure to stop. Fatique may have been a contributing factor.
Veh 1, traveling WB on Rte. 2, was distracted and ran a red light hitting Veh 2. Operator 1 cited for failure to
stop at a red light.
9
12-Jan-2010
Tuesday
11:44 PM
Driver lost control and hit a tree . The operator was arrested and cited for DUI and marked lanes violation.
Veh 2 stopped abruptly when the light turned yellow. Veh 1 rear-ended Veh 2 and pushed Veh 2 150 ft.
Operator 1 cited for following too close, failure to use care in stopping and speeds greater than reasonable.
Clear
Dry
Disregarded traffic
signs, signals, road
markings
Operating vehicle in
erratic, reckless,
careless, negligent or
aggressive manner
Veh 1, traveling WB on Rte. 2, ran a red light and hit Veh 2. Operator 1 was cited for failure to stop at a red
light.
20
49
56
75
36
45
Veh 1 was traveling EB on Rte. 2 at a high speed, lost control and hit the left guardrail 1st. Spinning out of
control, Veh 1 then crashed into the right side guardrail. During the crash, parts of veh 1 struck a second
vehicle.
10
22-Feb-2010
Monday
1:40 PM
Angle
Daylight
Clear
Dry
11
06-Mar-2010
Saturday
7:50 AM
Rear-end
Daylight
Clear
Dry
Disregarded traffic
signs, signals, road
markings
Operating vehicle in
erratic, reckless,
careless, negligent or
aggressive manner
24
Unknown
51
38
Veh 1 was traveling on Rte.2 WB at a high speed, failed to slow down or stop and rear-ended Veh 2. Operator
1 was cited for failure to use care in stopping, failure to stop for a red light, and warning for speed greater than
reasonable.
Veh 2 was travelling SB on Taylor Rd and was taking a right onto Rte. 2 WB when struck by Veh 1. Veh 1
rolled twice and then flipped over the guardrail, landing on the grassy median. Veh 1 says he didn't see the
red light and was cited for failure to stop.
Veh 1, traveling WB on Rte. 2, ran a red light and hit Veh 2. Operator 1 was cited for red light violation and no
license in possession.
Veh 1 stopped at the red light and Veh 2 rear-ended Veh 1. Operator 2 was cited for failure to use certain care
in stopping.
12
11-May-2010
Tuesday
10:35 AM
Angle
Daylight
Clear
Dry
Disregarded traffic
signs, signals, road
markings
13
16-May-2010
Sunday
11:05 AM
Rear-end
Daylight
Clear
Dry
Inattention
54
Unknown
14
18-Jun-2010
Friday
6:50 AM
Angle
Daylight
Clear
Dry
Disregarded traffic
signs, signals, road
markings
15
30-Jun-2010
Wednesday
1:35 PM
Angle
Daylight
Clear
Dry
Not Reported
Unknown
Unknown
16
06-Jul-2010
Tuesday
11:10 AM
Angle
Daylight
Clear
Dry
Not Reported
Unknown
Unknown
17
29-Jul-2010
Thursday
4:50 PM
Angle
Daylight
Clear
Dry
Inattention
Unknown
Unknown
61
Veh 3 was stopped at the red light on Taylor Rd (SB). When the light turned green, he proceeded to cross the
intersection when Veh 1, towing Veh 2 and traveling WB on Rt2, ran the red light. Veh 3 hit Veh 1 first, then
spinning out and hitting Veh 2 after. Operator 1 was cited for failure to stop.
Veh 1, traveling WB on Rte. 2, ran a red light and hit Veh 2. Operator 1 was cited for failure to stop at a red
light.
Veh 1, traveling WB on Rte. 2, ran the red light and struck Veh 2. Operator 1 was cited for running a red a
light.
Veh 2, traveling WB on Rte. 2, ran the red light and struck Veh 1. Operator 2 said he did not see the light and
was not able to stop before striking Veh 1.
Crash Data Summary Table
Massachusetts Avenue(Route 2/Route 111) at Taylor Road/Piper Road, Acton, MA
January 1, 2009 to December 31, 2011
Crash
No.
Crash Date
Crash Day
Crash Time
Manner of
Collision
Ambient
Light
Weather
Condition
Road
Surface
Condition
Driver Contributing
Code
Age
(D1)
Age
(D2)
Age
(D3)
Comments
Veh 2 slowed down to attempt to shift and Veh 1 was unable to stop in time and rear-ended Veh 2. Operator 1
received a written warning.
18
06-Aug-2010
Friday
5:05 PM
Rear-end
Daylight
Clear
Dry
Followed too closely
59
50
19
21-Sep-2010
Tuesday
8:56 AM
Angle
Daylight
Clear
Dry
Inattention
40
62
20
29-Sep-2010
Wednesday
9:10 AM
Angle
Daylight
Clear/Clear
Dry
Inattention
50
Unknown
21
10-Dec-2010
Friday
4:30 PM
Rear-end
Dusk
Clear
Dry
Followed too closely
27
28
Veh 2, traveling WB on Rte. 2, was crossing through the intersection with green light when Veh 1, travelling SB
on Taylor Rd, attempted to turn right. Veh 2 was unable to take evasive action in time and struck Veh 1.
Operator 1 was cited for failure to stop.
Veh 1 was traveling WB on Rte. 2 and was blinded by sun glare when the light was yellow. Veh 1 struck Veh 2
who was traveling SB on Taylor Rd with a green light.
22
26-Jan-2011
Wednesday
3:47 PM
Rear-end
Dusk
Snow
Wet
Unknown
Unknown
Unknown
23
28-Jan-2011
Friday
1:50 PM
Angle
Daylight
Clear
Dry
Disregarded traffic
signs, signals, road
markings
76
30
Dry
Disregarded traffic
signs, signals, road
markings
24
09-Feb-2011
Wednesday
7:40 AM
Angle
Daylight
Clear/Clear
Unknown
Unknown
Veh 2 was traveling EB on Rte. 2 and Veh 1 was merging from Rte. 111. Veh 1 cut-off Veh 2. Veh 2 changed
to the left lane erratically to avoid collision. Then Veh 2 passed Veh 1 from the left lane and then changed
lanes again to the right lane and "break-checked" Veh 1. Veh 1 then changed lanes again to the left lane, tried
to pass Veh 2 and swerved to the right and sideswiped Veh 2. Operator 1 was cited for failure to yield the
right of way, unsafe passing, and fail to stay in marked lanes.
Sunday
2:35 PM
Sideswipe,
same
direction
Daylight
Clear
Dry
Other improper action
24
32
26
14-Mar-2011
Monday
8:58 AM
Rear-end
Daylight
Cloudy/
Cloudy
Dry
Inattention
Unknown
Unknown
27
27-May-2011
Friday
9:26 PM
Angle
Dark ­
roadway not
lighted
Clear
Dry
Disregarded traffic
signs, signals, road
markings
21
56
Dry
Disregarded traffic
signs, signals, road
markings
29
18-Oct-2011
Friday
Tuesday
10:55 AM
5:08 PM
Angle
Vehicle 1 was stopped at Piper Rd at Rte. 2W, waiting for a gap to turn left. A vehicle from opposite direction
signaled her to proceed. As Veh 1 proceeded to turn left, the opposite vehicle changed his mind and went.
Veh 1 stopped abruptly and Veh 2 rear-ended Veh 1.
Veh 2, traveling WB on Rte. 2, ran a red light and hit Veh 1. Operator 2 was cited for red light violation and
failure to use care when stopping.
20-Feb-2011
29-Jul-2011
Veh 1 stops for traffic, Veh 2 fails to stop and rear-ends Veh 1. Then Veh 3 fails to stop and rear ends Veh 2,
causing Veh 2 to rear-end Veh 1 again. Operator 2 was citated for following too closely and Veh 3 was citated
for the same and for speeding.
Veh 1, traveling WB on Rte. 2, ran a red light and hit Veh 2. Operator 1 was cited for failure to stop at a red
light.
25
28
27
Daylight
Clear
Veh 1 stops for traffic, Veh 2 also stops behind Veh 1. Veh 3 failed to stop and rear-ended Veh 2 causing Veh
2 to rear-end Veh 1. Operator 3 was cited for fail to use caution when stopping.
Unknown
Veh 2 traveling WB when Veh 1 traveling SB on Taylor Rd ran the red light. Operator 1 was cited for failure to
stop at signal.
47
Veh 2 traveling NB on Piper Rd was crossing the intersection with Rte. 2 WB when Veh 1 traveling WB on Rte.
2 did not see the light and ran the red light striking Veh 2 on the side. Operator 1 was cited for red light
violation and impeded operation.
38
58
Veh 1 traveling WB on Rte. 2 ran the red light at the intersection with Taylor Rd and struck Veh 2 who was
crossing the intersection, traveling SB. Then Veh 2 spun around striking Veh 3, traveling NB, on the driver's
side.
30
Angle
Daylight
Clear
Dry
Disregarded traffic
signs, signals, road
markings
Clear
Dry
Made an improper
turn
34
46
30
11-Nov-2011
Friday
5:10 PM
Angle
Dark ­
roadway not
lighted
31
19-Nov-2011
Saturday
7:46 AM
Angle
Daylight
Clear
Dry
Disregarded traffic
signs, signals, road
markings
43
61
32
25-Nov-2011
Friday
11:35 AM
Rear-end
Daylight
Clear
Dry
Followed too closely
41
73
33
04-Dec-2011
Sunday
7:15 PM
Single vehicle
crash
Dark - lighted
roadway
Clear
Dry
Failure to keep in
proper lane or run-off
the road
25
34
26-Dec-2011
Monday
6:00 AM
Single vehicle
crash
Dark ­
roadway not
lighted
Clear
Dry
Fatigued / Asleep
49
54
Veh 2, traveling NB on Piper Rd attempted to make a left turn onto Rte. 2W and struck Veh 1 who was
traveling SB on Taylor Rd.
Veh 2 was traveling NB on Piper Rd when Veh 1, traveling WB on Rte. 2, ran the red light and struck Veh 2.
Operator 1 was cited for fail to stop at a red light.
Vehicles 1, 2, and 3 were traveling WB on Rte. 2 approaching the intersection with Taylor Rd. Veh 3 stopped.
Veh 1 stopped behind Veh 3. Veh 2 failed to stop rear-ending Veh 1 causing Veh 1 to rear-end Veh 3 as well.
Veh 1 was traveling EB on Rte. 2 approaching the intersection of Piper Rd when it ran off the road onto the
grassy median and hitting and destroying: a warning sign, a one-way sign, a DO NOT ENTER sign, and the
traffic signal pole. The operator was cited for marked lanes violation and speeding.
A vehicle was traveling WB on Rte. 2 when it suddenly swerved to the right, running off the road and hitting a
tree. Operator says he does not know what heppened.
Crash Data Summary Table
Massachusetts Avenue(Route 2/Route 111) at Taylor Road/Piper Road, Acton, MA
January 1, 2009 to December 31, 2011
Crash
No.
35
36
Crash Date
13-Jan-2009
09-Aug-2010
Crash Day
Tuesday
Monday
Crash Time
11:12 PM
5:15 PM
Manner of
Collision
Ambient
Light
Weather
Condition
Road
Surface
Condition
Driver Contributing
Code
Age
(D1)
Age
(D2)
Rear-end
Dark ­
roadway not
lighted
Clear
Wet
Inattention
Unknown
Unknown
Age
(D3)
Comments
Vehs 1 and 2 were traveling WB on Rt 2, near Taylor Rd. Operator 1 got distracted and rear-ended Veh 2.
Rear-end
Daylight
Clear
Dry
Followed too closely
25
55
21
Clear
Dry
Followed too closely
62
22
51
Followed too closely
54
28
37
06-Dec-2010
Monday
6:36 PM
Rear-end
Dark ­
roadway not
lighted
38
19-Aug-2011
Friday
5:40 PM
Rear-end
Daylight
Clear
Dry
39
10-Sep-2011
Saturday
10:20 AM
Rear-end
Source: Acton Police Department Reports provided by MassDOT
Daylight
Not Reported
Dry
Vehs 1, 2, and 3 were traveling WB on Rte. 2. Vehs 1 and 2 stopped for the traffic light. Veh 3 failed to stop
rear-ending Veh 2, who then rear-ended Veh 1. Operator 3 received a verbal warning for failure to use care in
stopping.
Vehs 1, 2, and 3 were traveling WB on Rte. 2. Vehs 2 and 3 stopped for the traffic light. Veh 1 failed to stop
rear-ending Veh 2, who then rear-ended Veh 3. Operator 1 was cited for failure to use care in stopping.
Vehs 1 and 2 were traveling WB on Rte. 2, near Taylor Rd. Operator 2 did not stop in time and rear-ended
Veh 1.
Vehs 1 and 2 were traveling SB on Piper Road, past Route 2, by a T intersection. Veh 1 rear-ended Veh 2.
Unknown
Unknown
Crash Data Summary Tables and Charts
Massachusetts Avenue (Rt. 2/Rt. 111) at Piper Road / Taylor Road
CRASH MONTH
14%
12%
13%
10%
10%
13%
10%
10%
8%
8%
8%
8%
8%
5%
6%
5%
4%
2%
2%
0%
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
CRASH DAY OF THE WEEK
28%
30%
25%
21%
20%
15%
15%
13%
10%
10%
8%
5%
5%
0%
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
CRASH TIME OF DAY
20%
18%
15%
15%
15%
10%
10%
10%
8%
8%
8%
5%
5%
0%
3%
0%
6AM8AM
8AM10AM
10AM12PM
12PM2PM
2PM4PM
4PM6PM
6PM8PM
8PM10PM
10PM12AM
12AM­
2AM
0%
2AM4AM
4AM­
6AM
CRASH MANNER OF COLLISION
50%
46%
38%
40%
30%
20%
7%
10%
3%
3%
3%
Head-on
Sideswipe
Not Reported
0%
Angle
Single Vehicle
Crash
Rear-end
Crash Data Summary Tables and Charts
Massachusetts Avenue (Rt. 2/Rt. 111) at Piper Road / Taylor Road
CRASH LIGHT CONDITION
67%
70%
60%
50%
40%
30%
18%
20%
10%
5%
10%
0%
Daylight
Dusk
Dark Lighted
Roadway
Dark ­
Not Lighted
Roadway
CRASH WEATHER CONDITION
90%
82%
80%
70%
60%
50%
40%
30%
20%
10%
7%
3%
3%
5%
Snow
Not Reported
0%
Clear
Cloudy
Rain
CRASH ROAD SURFACE
100%
87%
80%
60%
40%
13%
20%
0%
Dry
Wet
CRASH DRIVER AGES
30%
26%
25%
21%
20%
15%
10%
13%
10%
15%
8%
5%
2%
5%
0%
0%
15-20
21-29
30-39
40-49
50-59
60-69
70-79
80+
Unknown
Appendix D. Road Safety Audit References
Road Safety Audit References
Massachusetts Traffic Safety Toolbox, Massachusetts Highway Department,
www.mhd.state.ma.us/safetytoolbox.
Road Safety Audits, A Synthesis of Highway Practice. NCHRP Synthesis 336. Transportation Research
Board, National Cooperative Highway Research Program, 2004.
Road Safety Audits. Institute of Transportation Engineers and U.S. Department of Transportation, Federal
Highway Administration, www.roadwaysafetyaudits.org.
FHWA Road Safety Audit Guidelines. U.S. Department of Transportation, Federal Highway
Administration, 2006.
Road Safety Audit, 2nd edition. Austroads, 2000.
Road Safety Audits. ITE Technical Council Committee 4S-7. Institute of Transportation Engineers,
February 1995.
FHWA Signalized Intersections: Informational Guide. U.S. Department of Transportation, Federal
Highway Administration, publication FHWA-HRT-04-091, 2004.
Manual on UniformTraffic Control Devices (MUTCD), U.S. Department of Transportation, Federal
Highway Administration, 2009.