ROAD SAFETY AUDIT
Groton Road (Route 40) at Oak Hill Road
Town of Westford
March 20, 2013
Prepared For:
MassDOT Highway Division
Prepared By:
BETA Group, Inc.
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Table of Contents
Project Data .................................................................................................................................1
Background .................................................................................................................................2
Project Description .....................................................................................................................2
Audit Observations .....................................................................................................................5
Potential Safety Enhancements .................................................................................................7
Summary of Road Safety Audit.................................................................................................9
List of Appendices
Appendix A.
Appendix B.
Appendix C.
Appendix D.
RSA Meeting Agenda
RSA Audit Team Contact List
Detailed Crash Data
Traffic Volume Data
List of Figures
Figure 1.
Location Map ......................................................................................................................... 3
List of Tables
Table 1.
Table 2.
Table 3.
Participating Audit Team Members ....................................................................................... 1
Estimated Time Frame and Costs Breakdown ....................................................................... 7
Potential Safety Enhancement Summary ............................................................................. 10
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Project Data
A Road Safety Audit for the intersection of Groton Road (Route 40) and Oak Hill Road was held on
March 14, 2013 at the Westford Town Hall in Westford, MA. As indicated in Table 1, the audit team
consisted of representatives from Federal, State, Regional and Local agencies and included a crosssection of engineering, planning and emergency response expertise.
Table 1. Participating Audit Team Members
Audit Team Member
Agency/Affiliation
Bonnie Polin
MassDOT Highway Division – Safety Section
Corey O’Connor
MassDOT Highway Division – Safety Section
Justin Howard
NMCOG
Lt. Donald Parsons
Westford Fire Department
Paul Starratt
Westford Town Engineer
Chris Kluchman
Westford Director of Land Use Management
Promise Otaluka
FHWA
Peter Calves
MassDOT Highway Division (Intern)
Qing Qing You
MassDOT Highway Division (Intern)
Jeremy Downs
Westford Assistant Town Engineer
Michael Croteau
Westford Police Department
Richard Barrett
Westford Highway Superintendent
Alolade Campbell
MassDOT Highway Division – District 3
Greg Lucas
BETA Group, Inc.
Justin Curewitz
BETA Group, Inc.
Page 1
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Background
The Federal Highway Administration defines a Road Safety Audit (RSA) as the formal safety examination
of an existing or future road or intersection by an independent, multidisciplinary team. The purpose of an
RSA is to identify potential safety issues and possible opportunities for safety improvements considering
all roadway users. A Road Safety Audit was scheduled for the intersection of Groton Road (Route 40) and
Oak Hill Road in Westford because it has been identified as a high crash location within the Northern
Middlesex Council of Governments (NMCOG) region. The RSA is intended to identify potential short and
long term safety improvements that can be made at the intersection, which can then be implemented
through general maintenance for short term low cost improvements or potentially incorporated into a
reconstruction project for longer term measures.
Project Description
The intersection of Groton Road (Route 40) and Oak Hill Road, shown in Figure 1, is located in the
northeastern portion of Westford. Groton Road is functionally classified as an Urban Principal Arterial,
while Oak Hill Road is classified as an Urban Minor Arterial. Both roadways are under Town of Westford
jurisdiction. Route 40 is an important regional route, providing access from Westford and Groton to
Route 3, which has an interchange with Route 40 approximately one mile east of the study intersection.
Route 40 is an established evacuation route for Groton and for the northern portion of Westford. Oak Hill
Road provides a connection from Route 40 to the Nabnasset neighborhood, and provides a north-south
connection to other roadways that connect to Westford’s town center.
Groton Road and Oak Hill Road form a four-way intersection, with Oak Hill Road under STOP sign
control. Groton Road generally provides a single travel lane in each direction along its length, but was
widened to provide a two-way left turn lane between Russell’s Way and Oak Hill Road, a distance of
approximately 600 feet. The exact date of the widening improvement is unknown, but it is assumed to
have been implemented over ten years ago. The two-way left turn lane accommodates eastbound left turns
at Oak Hill Road, with an opposing left turn lane provided in the westbound direction. Stop lines are
painted across the end of the left turn lanes, which is atypical and technically incorrect, since left turns on
an uncontrolled approach must yield to opposing traffic but are not required to stop. The two-way left turn
lane is delineated with a single, solid yellow line on both sides, while the westbound left turn lane is
delineated by a double yellow center line on the
left edge and a single white line on the right edge.
Solid white edge lines are offset one to two feet
from the pavement edge.
Oak Hill Road northbound provides a two lane
approach. It was noted that Oak Hill Road was
widened slightly to accommodate the two lane
approach. A solid white line separates the two
lanes, extending approximately 60 feet from the
stop line. A double yellow center line and solid
Oak Hill Road at Groton Road
Page 2
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STUDY INTERSECTION
Road Safety Audit
Route 40 (Groton Road)
at Oak Hill Road
Westford, MA
Figure 1
Location Map
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
white edge lines are provided. Oak Hill Road north of Groton Road is a dead end road providing access to
adjacent businesses, including the Rapid Refill gas/convenience/Dunkin’ Donuts shop, a manufacturing
facility, and an empty site slated for multi-use redevelopment in the near future. The Rapid Refill located
on the northwest corner of the intersection has driveways on both Groton Road and Oak Hill Road, and
local officials noted that drivers are known to favor the driveway on Groton Road due to visibility
constraints at the Oak Hill Road approach to Groton Road. Additional land uses at the intersection include
a Lowell Five Savings Bank branch on the southwest corner and a manufacturing facility on the northeast
corner. The southeast corner of the intersection is conservation land.
A crosswalk is provided across the west leg of the intersection, painted solid yellow and delineated by
white lines. Fluorescent yellow-green crosswalk warning signs are provided at the crosswalk in each
direction of travel. A sidewalk is provided along the west side of Oak Hill Road. No sidewalks are
provided on either side of Groton Road in the vicinity of the intersection.
Crash data provided by the Westford Police Department and summarized by NMCOG show fourteen
crashes from January 2010 to September 2012. A collision diagram and crash summary are included in
the Appendix. The crash summary shows eighteen crashes, but four were excluded because there were
determined to be outside the study area. The remaining crashes are mapped on the collision diagram.
Seven of the fourteen crashes occurred at site driveways immediately adjacent to the intersection. Three
of the seven involved vehicles entering or exiting the Rapid Refill, one involved a vehicle entering or
exiting Lowell Five Savings Bank, and the remaining three involved business driveways on the north side
of Groton Road east of Oak Hill Road. Of particular note is the fact that four of these crashes are rear end
crashes, suggesting that through vehicles on Groton Road are running into vehicles that either stop to
turn, stop because the vehicle in front of them turns, or stop or slow because of another vehicle entering
or exiting a driveway. The number of crashes related to site drives indicates that any improvements
recommended for the intersection must consider driveway operation as well as intersection operation.
The remaining crashes at the intersection consist of angle crashes and one head on crash. The head on
crash involved a vehicle swerving around a stopped vehicle and colliding with a vehicle in the opposing
left turn lane. Four angle crashes, including one fatal crash, involved a vehicle departing Oak Hill Road
and a westbound through vehicle, while two angle crashes involved a vehicle departing Oak Hill Road
and an eastbound through vehicle.
Automatic Traffic Recorder (ATR) counts and Manual Turning Movement (MTM) counts were provided
by NMCOG. ATR data were recorded in 2009 for Oak Hill Road and show that the average daily traffic
(ADT) is 4,800 vehicles per day (vpd). MTM data were recorded at the intersection in December 2012
for both the morning and afternoon peak periods. The morning peak hour occurred from 8:00 to 9:00
AM. Of note were 531 eastbound through vehicles on Groton Road, and 154 right turns from Oak Hill
Road to Groton Road eastbound. This confirms that Groton Road is a popular commuter roadway.
The afternoon peak hour occurred from 5:00 to 6:00 PM. During the afternoon peak hour, the converse of
the morning peak hour flow occurs, with 502 through vehicles and 223 left turning vehicles from Groton
Road westbound. Complete ATR and MTM count data are included in the Appendix.
Page 4
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Audit Observations
Following a brief introduction to the RSA process and a summary of existing crash and traffic volume
information, the audit participants were asked to discuss safety issues at the intersection of Groton Road
(Route 40) and Oak Hill Road. Audit participants then conducted a site visit as a group, at which time
they offered observations on safety concerns and deficiencies. A summary of those major safety
considerations is as follows:

Stop Sign Violations – Violations were noted for right turns from Oak Hill Road to Groton Road
eastbound. Drivers employ a rolling stop technique for this heavily traveled movement, which may be
a factor in crashes between eastbound through vehicles and vehicles departing Oak Hill Road. OUI
violations were also noted involving vehicles failing to stop at Oak Hill Road and traveling straight
across Groton Road.

Site Drive Operation – Vehicles entering and exiting businesses adjacent to the intersection affect
operations at the intersection, as evidenced by the seven crashes related to site driveways. Any further
study of the intersection and development of improvements must consider site drive access and
operation.

Speed – Speeding along Groton Road was noted as a safety concern, both alone and in tandem with
site drive operation. No speed data was available for study, but it was suggested that through vehicles
are traveling in excess of the 40 mph limit established for Groton Road. At the same time, vehicles
may also be slowing when approaching the intersection to turn into Oak Hill Road or one of the
adjacent businesses. This variance in approach speeds presents challenges in judging acceptable gaps
for drivers departing Oak Hill Road or one of the adjacent site drives. This may be a factor in crashes
at site driveways.

Visibility – A number of visibility constraints were noted at the intersection.
o Vegetation overgrowth was not observed on the day of the audit, but was noted to exist
during peak growth season. Shrubbery along the northern edge of Groton Road on the
Rapid Refill property impacts visibility for vehicles departing Oak Hill Road southbound,
while small trees with low branches bordering the Lowell Five Savings Bank were said to
impact visibility for vehicles departing Oak Hill Road northbound. It was noted that
current Westford town bylaws do not allow the Town to trim on private property, but that
both property owners regularly maintain their landscaping. Vegetation bordering the
conservation land on the southeast corner of the intersection also may impact visibility to
the right for vehicles departing Oak Hill Road northbound.
o A solid fence bordering the property immediately west of Rapid Refill was also noted,
although it has recently been damaged during snow removal. This fence may impact
visibility for drivers departing the Rapid Refill driveway on Groton Road.
Page 5
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
o Utility poles are spaced such that they create a wall or picket fence effect for drivers
traveling along Groton Road. Audit participants unfamiliar with the area had a difficult
time identifying the location of Oak Hill Road, especially given the number of site
driveways and other access points along Groton Road. Town personnel noted that the
poles carry subtransmission lines, which makes relocation difficult and costly. Utility
poles were moved to the edge of the town right-of-way when Groton Road was widened
to provide a two-way left turn lane.
Shrubs and Bent/Missing No Parking Signs bordering Rapid Refill
Trees bordering Lowell Five Savings Bank

Intersection Awareness - In addition to the utility pole effect noted above, the lack of intersection
warning signs on Groton Road eastbound make it difficult to identify the location of Oak Hill Road.

Signage –It was noted that a No Parking sign located on the north side of Groton Road adjacent to the
Rapid Refill was bent, and that street name signs at the intersection are set back too far to be
effective.

Grading/Alignment – It was noted that the north leg of Oak Hill Road is lower than Groton Road,
which exacerbates visibility concerns for vehicles turning onto Groton Road. Drainage deficiencies
related to grading existed in this area until the recent addition of a catch basin on the northeast corner
of the intersection.

Emergency Vehicles – The intersection is important for emergency vehicle response from the fire
station located on Oak Hill Road south of Groton Road.

Encroachment – Vehicles turning left from Groton Road westbound to Oak Hill Road were observed
on the day of the audit crossing the center line and encroaching on the approach lane. It is unclear if
any crashes at the intersection occurred as a result of this encroachment.

Painted Stop Bar – The stop bar across the left turn lanes is potentially confusing, since vehicles by
law do not have to stop before making a left turn from Groton Road. Vehicles only must yield to
approaching traffic.
Page 6
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Potential Safety Enhancements
Audit participants identified safety issues and recommended potential improvements to address these
issues. Audit participants were encouraged to consider both short and long term improvements for each
issue. Each improvement considered has been categorized as short-term, mid-term, or long-term based on
the definitions shown in Table 2. Additionally, a cost category has been assigned to each improvement
based on the parameters set forth in Table 2.
Table 2. Estimated Time Frame and Costs Breakdown
Time Frame
Short-term

<1 year
Costs
Low
Mid-term
1–3 years
Medium
Long-term
>3 years
High
<$10,000
$10,000–$50,000
>$50,000
Consider overall improvement strategies related to traffic control. Three separate strategies were
discussed at the audit and are detailed below.
o Install a flashing beacon. The potential effectiveness of a flashing beacon was discussed
for the intersection of Groton Road and Oak Hill Road. It was determined that a flashing
beacon can be beneficial at this location because it would increase awareness of the
intersection for vehicles approaching on Groton Road, and increase awareness of the stop
condition for vehicles approaching on Oak Hill Road. It was noted, however, that stop
sign violations on Oak Hill Road are likely occurring from regular users who know that
the stop sign is there, but choose to ignore it. A flashing beacon is a short-term, medium
cost improvement.
o Consider a roundabout. A roundabout should be considered as part of any further study of
the intersection. It was suggested that adequate right-of-way may not exist to
accommodate a roundabout. This is a long-term, high cost improvement.
o Consider installation of a traffic signal. A traffic signal would provide a protected
movement for vehicles departing Oak Hill Road and can provide a protected movement
for left turns from Groton Road. Traffic signal warrant analysis is necessary to determine
if signal installation is warranted. Installation of a traffic signal is a long-term, high cost
improvement. A traffic signal installation should include emergency preemption
equipment.

Consider site drive operation in any overall reconstruction efforts at the intersection. The prevalence
of crashes involving vehicles entering or exiting site drives requires careful consideration of site drive
operation and its impact on the intersection. This must be considered as part of any long-term
improvements.
Page 7
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.

Continue to enforce the 40 mph speed limit on Groton Road. The Town should continue enforcement
in this area as a short-term, ongoing improvement, the cost of which is reduced enforcement
elsewhere in the Town.

Consider islands on the Oak Hill Road approach. Two different types of medians were discussed. It is
unknown if adequate right-of-way exists for either median treatment. Further study is required in both
instances to determine feasibility and adequacy of right-of-way.
o Install a median separating the approach and departure lanes. This would prevent vehicles
from encroaching on the approach lane when turning left from Groton Road. In addition
to right-of-way concerns, this option must be studied to determine if emergency vehicles
and trucks can be accommodated. This is a mid-term, medium cost improvement.
o Install a delta island separating the left and right turn lanes. This would channelize the
right turn lane, and provide a location for a more visible stop sign
installation. This is a mid-term, medium cost improvement.

Replace word “Stop Ahead” sign on Oak Hill Road with a graphical W3-1a
“Stop Ahead” sign. The graphical stop ahead sign may be more visible due to the
red graphic incorporated in the sign legend. This is a short-term, low cost
improvement.

Work with property owners to manage vegetation on private property. It was noted that Town bylaws
do not allow the Town to trim vegetation on private property, but that property owners typically
maintain their landscaping so that sight obstructions are minimized. If private vegetation becomes a
problem, the Town should work with the property owners so that adequate visibility is maintained.
This is a short-term, ongoing low cost improvement.

Trim vegetation on the southeast corner of the intersection. The southeast corner is conservation land
under Town control. This vegetation should be continually maintained so that it does not obstruct
visibility at the intersection. This is a short-term, ongoing low cost improvement.

Provide an intersection warning sign on Groton Road eastbound in advance of
Oak Hill Road, and add street name plaques to intersection warning signs in both
directions. Town personnel noted that this sign would be installed immediately
following the audit. A supplemental black on yellow “OAK HILL RD” plaque
should be installed under the intersection warning sign to help drivers identify not
just the intersection, but the intersecting street. This is a short-term, low cost
improvement.

Repair or replace No Parking signs along Groton Road bordering the Rapid Refill property. These
signs were installed to prevent drivers from parking on the roadway edge when patronizing Rapid
Refill or Dunkin’ Donuts. These signs should be repaired or replaced as a short-term, low cost
improvement.
Page 8
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.

Raise the alignment of the north leg of Oak Hill Road. The roadway is slightly lower than the
intersection, which exacerbates existing visibility concerns for vehicles departing this approach. The
alignment should be raised as part of any overall reconstruction efforts at the intersection. This is a
long-term, high cost improvement.

Remove the painted stop bar across the left turn lanes on Groton Road. Town personnel stated that
they would not repaint these lines as part of regular line painting maintenance. Removal is a shortterm, low cost improvement.
Summary of Road Safety Audit
Table 3 summarizes potential recommendations discussed by the audit team. The recommendations are
categorized based on the potential safety payoff, as well as by time frame and cost. The safety payoff is a
qualitative judgment of the effectiveness of the potential safety improvements. Each recommendation has
a responsibility assigned to it stating whether MassDOT or the Town of Westford would be responsible
for implementing the recommended improvement. All improvements have an order of magnitude cost
assigned.
Page 9
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Table 3. Potential Safety Enhancement Summary
Safety Issue
Safety Enhancement
Responsibility
Safety
Payoff
Time Frame
Cost
Consider overall improvement strategies related to traffic
control. The first three improvements listed present different
levels of treatment for these issues.
Stop Sign Violations,
Intersection Awareness
Install a flashing beacon.
Town
Medium
Short-term
$40,000
Stop Sign Violations,
Intersection Awareness
Consider a roundabout. This requires further study.
Town
High
Long-term
High
Town
High
Long-term
$200,000
Stop Sign Violations,
Consider installation of a traffic signal. This requires a traffic
Intersection Awareness,
signal warrant analysis.
Emergency Vehicles
Site Drive Operation
Consider site drive operation in any overall reconstruction
efforts at the intersection.
Town
High
Long-term
TBD
Speed
Continue to enforce the 40 mph limit on Groton Road.
Town
Medium
Short-term
$0 (Reduced
enforcement
elsewhere)
Encroachment
Consider installing a median separating the approach and
departure lanes on Oak Hill Road.
Town
Medium
Mid-term
$25,000
Stop Sign Violations
Consider installing a delta island separating the left and right
turn lanes on Oak Hill Road.
Town
Medium
Mid-term
$25,000
Stop Sign Violations
Replace word “Stop Ahead” sign on Oak Hill Road with a
graphical W3-1a “Stop Ahead” sign.
Town
Medium
Short-term
$250
Visibility
Work with property owners to manage vegetation on private
property.
Town/
Property
Owners
Medium
Short-term
$0
Visibility
Trim vegetation on the southeast corner of the intersection.
Town
Medium
Short-term
$500
Intersection Awareness
Provide an intersection warning sign on Groton Road EB in
advance of Oak Hill Road, and add street name plaques to
intersection warning signs on both directions.
Town
Medium
Short-term
$500
Signage
Repair or replace No Parking signs along Groton Road
bordering the Rapid Refill property.
Town
Low
Short-term
$500
Page 10
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Table 3. Potential Safety Enhancement Summary
Responsibility
Safety
Payoff
Time Frame
Cost
Raise the alignment of the north leg of Oak Hill Road.
Town
Medium
Long-term
TBD
Remove the painted stop bar across the left turn lanes on
Groton Road.
Town
Low
Short-term
$500
Safety Issue
Safety Enhancement
Grading/Alignment
Painted Stop Bar
Page 11
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Appendix A. RSA Meeting Agenda
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Appendix B. RSA Audit Team Contact List
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Appendix C. Detailed Crash Data
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Crash Number Crash Day
Manner of
Crash Date Time of Day Collision
Light Condition
Weather
Condition
Road
Surface
Driver Contributing Code
Number
Vehicles
Number
Injured
Comments
1
2
3
4
5
6
7
8
Tuesday
Monday
Thursday
Monday
Wednesday
Thursday
Monday
Saturday
5/4/2010
5/24/2010
6/17/2010
7/19/2010
8/11/2010
9/23/2010
10/4/2010
1/29/2011
6:25 AM
5:12 PM
5:51 PM
3:34 PM
12:44 PM
5:01 PM
5:08 PM
6:24 PM
Angle
Rear End
Rear End
Rear End
Angle
Angle
Angle
Angle
Daylight
Daylight
Daylight
Daylight
Daylight
Daylight
Daylight
Dark - roadway not lighted
Cloudy
Clear
Cloudy
Clear
Clear
Clear
Cloudy
Cloudy
Wet
Dry
Wet
Dry
Dry
Dry
Dry
Wet
Failed to yield right of way
No improper Driving
Followed too closely
No improper Driving
Disregarded traffic signs, signals, and markings
Disregarded traffic signs, signals, and markings
Failed to yield right of way
Inattention
2
3
4
4
2
2
2
2
0
0
0
1
0
0
1
1
9
12
15
16
17
18
Tuesday
Wednesday
Wednesday
Wednesday
Sunday
Sunday
2/8/2011
1/18/2012
3/28/2012
4/12/2012
8/26/2012
9/16/2012
4:37 PM
9:47 PM
8:41 AM
8:17 AM
5:14 PM
2:55 PM
Head On
Angle
Rear End
Angle
Angle
Angle
Daylight
Dark - lighted roadway
Daylight
Daylight
Daylight
Daylight
Clear
Clear
Cloudy
Clear
Clear
Clear
Dry
Dry
Dry
Dry
Dry
Dry
Swerving or avoiding due to vehicle
Failed to yield right of way
Followed too closely
Inattention
Disregarded traffic signs, signals, and markings
Disregarded traffic signs, signals, and markings
2
2
2
2
2
2
0
0
0
0
4
3
Daylight
Clear
Dry
Inattention
2
0
Dusk
Daylight
Clear
Clear
Dry
Dry
Inattention
No improper Driving
1
2
1
0
427 Groton Rd
409 Groton Rd hit and run
on a pedestrian
540 Groton Rd
Dark - lighted roadway
Cloudy
Dry
No improper Driving
1
0
Vehicle struck Deer
Not in the area
10
Monday
6/6/2011
11
13
Monday
Friday
10/17/2011
3/9/2012
14
Monday
3/12/2012
7:11 AM Head On
Single Vehicle
6:19 PM Crash
12:01 PM Angle
Single Vehicle
11:55 PM Crash
498 Groton Rd
508 Groton Rd
506 Groton Rd
499 Groton Rd
498 Groton Rd
swerved due to third car
inching out of Oak Hill Rd
504 Groton Rd
498 Groton Rd
Information is based on Westford Crash Reports, January 2010 - September 2012
3
Manner of Collision
70%
60%
50%
40%
30%
20%
10%
0%
Angle
Rear End
Head On
Single Vehicle Crash
Road Surface
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Dry
Wet
Day of Week
30%
25%
20%
15%
10%
5%
0%
Monday
Tuesday Wednesday Thursday
Friday
Saturday
Sunday
4
Lighting
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Daylight
Dark-roadway not
lighted
Dark -Lighted
roadway
Dusk
Time of Day
60%
50%
40%
30%
20%
10%
0%
6:00AM-10:00 AM
10:00 AM-2:00PM
2:00PM-6:00PM
6:00PM-10:00PM
10:00PM-2:00AM
2:00AM-6:00AM
5
Road Safety Audit—Groton Road (Route 40) at Oak Hill Road—Westford, MA
Prepared by BETA Group, Inc.
Appendix D. Traffic Volume Data
Morning Turn Count Summary
Location: Oak Hill Rd at Rte 40, Westford
Day of week: Thursday
Peak hour: 08:00 - 09:00
Weather: Cloudy
Date: 12/13/12
Analyst: JH
Total vehicle traffic
Interval
starts
Southbound
Left
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Left
2
Thru
106
30
0
42
1
12
33
9
3
8
7
Total
9
1
0
9
37
6
5
13
Right
33
7:15
9
5
0
14
45
12
5
9
7:30
14
4
0
19
51
6
5
5
7:45
6
0
0
17
45
10
6
8:00
3
1
0
24
54
11
8:15
4
2
3
16
52
4
8:30
10
3
0
21
54
7
4
4
42
0
138
8
291
8:45
6
3
0
20
55
5
11
8
34
2
147
9
300
7:00
Thru
Westbound
Right
4
225
112
15
256
97
12
256
0
129
12
270
39
1
120
14
279
39
1
135
5
276
Car traffic
Interval
starts
Southbound
Thru
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Left
2
Thru
103
30
0
41
1
12
33
3
39
7
39
Total
9
1
0
9
34
6
5
13
Right
32
7:15
8
4
0
14
44
7
5
9
7:30
13
3
0
19
48
6
5
5
7:45
6
0
0
16
44
7
5
8:00
3
1
0
24
49
10
8
8:15
4
2
1
16
51
3
7
8:30
10
3
0
19
54
6
4
4
42
0
135
8
285
8:45
5
2
0
20
53
5
10
8
34
2
143
9
291
7:00
Left
Westbound
Right
4
218
112
14
247
95
11
247
0
126
12
261
1
118
14
270
1
135
4
270
6
Morning Turn Count Summary
Truck traffic
Interval
starts
Southbound
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Right
Left
Thru
Total
Right
7:00
0
0
0
0
3
0
0
0
1
0
3
0
7
7:15
1
1
0
0
1
5
0
0
0
0
0
1
9
7:30
1
1
0
0
3
0
0
0
1
0
2
1
9
7:45
0
0
0
1
1
3
1
0
0
0
3
0
9
8:00
0
0
0
0
5
1
1
0
0
0
2
0
9
8:15
0
0
2
0
1
1
1
0
0
0
0
1
6
8:30
0
0
0
2
0
1
0
0
0
0
3
0
6
8:45
1
1
0
0
2
0
1
0
0
0
4
0
9
Bicycle traffic
Interval
starts
Southbound
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Right
Left
Thru
Total
Right
7:00
0
0
0
0
0
0
0
0
0
0
0
0
0
7:15
0
0
0
0
0
0
0
0
0
0
0
0
0
7:30
0
0
0
0
0
0
0
0
0
0
0
0
0
7:45
0
0
0
0
0
0
0
0
0
0
0
0
0
8:00
0
0
0
0
0
0
0
0
0
0
0
0
0
8:15
0
0
0
0
0
0
0
0
0
0
0
0
0
8:30
0
0
0
0
0
0
0
0
0
0
0
0
0
8:45
0
0
0
0
0
0
0
0
0
0
0
0
0
Pedestrian volumes
Interval
starts
NE
Left
NW
Right
Total
Left
SW
Right
Total
Left
SE
Right
Total
Left
Right
Total
Total
7:00
0
0
0
0
0
0
0
0
0
0
0
0
0
7:15
0
0
0
0
0
0
0
0
0
0
0
0
0
7:30
0
0
0
0
0
0
0
0
0
0
0
0
0
7:45
0
0
0
0
0
0
0
0
0
0
0
0
0
8:00
0
0
0
0
0
0
0
0
0
0
0
0
0
8:15
0
0
0
1
0
1
0
0
0
0
0
0
1
8:30
0
0
0
0
0
0
0
0
0
0
0
0
0
8:45
0
0
0
0
0
0
0
0
0
0
0
0
0
7
Morning Turn Count Summary
Intersection Peak Hour
Southbound
Vehicle
Total
Factor
Approach
Factor
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Right
Left
Thru
Total
Right
23
9
3
81
215
27
32
22
154
4
540
36
1146
0.57
0.75
0.25
0.84
0.98
0.61
0.73
0.69
0.92
0.5
0.92
0.64
0.91
0.67
0.91
0.96
0.92
Westbound
Northbound
Eastbound
Peak Hour Vehicle Summary
Southbound
Left
Right
Left
Right
24
Left
Thru
Left
Right
35
Total
22
8
1
79
Thru
207
29
22
Right
154
4
Thru
531
Truck
1
1
2
2
8
3
3
0
0
0
9
1
30
Bicycle
0
0
0
0
0
0
0
0
0
0
0
0
0
Car
Thru
1116
Peak Hour Pedestrians
NE
Pedestria
ns
Left
NW
Right
0
Total
0
Left
0
SW
Right
1
Total
0
Left
1
SE
Right
0
Total
0
Left
0
Right
0
Total
Total
0
0
1
8
Afternoon Turn Count Summary
Location: Oak Hill Rd at Route 40, Westford
Date: 2012-12-05
Peak hour: 17:00 - 18:00
Day of week: Wednesday
Weather: sun
Analyst: drt
Total vehicle traffic
Interval
starts
Southbound
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Left
Thru
Total
16:00
2
1
0
45
92
9
6
0
Right
39
Right
1
76
7
278
16:15
4
0
1
47
107
10
8
1
38
0
88
6
310
16:30
8
1
4
58
109
7
10
1
36
0
72
5
311
16:45
5
3
0
37
103
9
15
3
35
0
75
9
294
17:00
5
1
1
60
107
7
11
1
26
0
68
13
300
17:15
5
0
1
61
137
7
5
2
28
0
93
7
346
17:30
5
0
0
53
124
16
13
2
31
0
69
12
325
17:45
2
1
0
49
134
3
10
1
27
0
85
14
326
Car traffic
Interval
starts
Southbound
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
16:00
2
1
0
45
92
8
6
0
Right
35
16:15
4
0
1
47
106
10
8
1
16:30
8
1
3
57
109
7
9
1
16:45
5
3
0
37
102
9
15
3
17:00
5
0
1
60
106
6
11
1
17:15
5
0
1
61
137
7
5
2
17:30
5
0
0
52
123
16
13
2
17:45
2
1
0
49
133
3
10
1
Left
Thru
Total
Right
1
74
7
271
38
0
86
6
307
36
0
72
5
308
33
0
75
9
291
26
0
68
13
297
28
0
90
7
343
31
0
66
12
320
27
0
84
12
322
9
Afternoon Turn Count Summary
Truck traffic
Interval
starts
Southbound
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Right
Left
Thru
Total
Right
16:00
0
0
0
0
0
1
0
0
4
0
2
0
7
16:15
0
0
0
0
1
0
0
0
0
0
2
0
3
16:30
0
0
1
1
0
0
1
0
0
0
0
0
3
16:45
0
0
0
0
1
0
0
0
2
0
0
0
3
17:00
0
1
0
0
1
1
0
0
0
0
0
0
3
17:15
0
0
0
0
0
0
0
0
0
0
3
0
3
17:30
0
0
0
1
1
0
0
0
0
0
3
0
5
17:45
0
0
0
0
1
0
0
0
0
0
1
2
4
Bicycle traffic
Interval
starts
Southbound
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Right
Left
Thru
Total
Right
16:00
0
0
0
0
0
0
0
0
0
0
0
0
0
16:15
0
0
0
0
0
0
0
0
0
0
0
0
0
16:30
0
0
0
0
0
0
0
0
0
0
0
0
0
16:45
0
0
0
0
0
0
0
0
0
0
0
0
0
17:00
0
0
0
0
0
0
0
0
0
0
0
0
0
17:15
0
0
0
0
0
0
0
0
0
0
0
0
0
17:30
0
0
0
0
0
0
0
0
0
0
0
0
0
17:45
0
0
0
0
0
0
0
0
0
0
0
0
0
Pedestrian volumes
Interval
starts
NE
Left
NW
Right
Total
Left
SW
Right
Total
Left
SE
Right
Total
Left
Right
Total
Total
16:00
0
0
0
0
0
0
0
0
0
0
0
0
0
16:15
0
0
0
0
0
0
0
0
0
0
0
0
0
16:30
0
0
0
0
0
0
0
0
0
0
0
0
0
16:45
0
0
0
0
0
0
0
0
0
0
0
0
0
17:00
0
0
0
0
0
0
0
0
0
0
0
0
0
17:15
0
0
0
0
0
0
0
0
0
0
0
0
0
17:30
0
0
0
0
0
0
0
0
0
0
0
0
0
17:45
0
0
0
0
0
0
0
0
0
0
0
0
0
10
Afternoon Turn Count Summary
Intersection Peak Hour
Southbound
Vehicle
Total
Factor
Approach
Factor
Left
Thru
Westbound
Right
Left
Thru
Northbound
Right
Left
Thru
Eastbound
Right
Left
Thru
Total
Right
17
2
2
223
502
33
39
6
112
0
315
46
1297
0.85
0.5
0.5
0.91
0.92
0.52
0.75
0.75
0.9
0
0.85
0.82
0.91
0.75
0.92
0.85
0.9
Westbound
Northbound
Eastbound
Peak Hour Vehicle Summary
Southbound
Left
17
1
2
Left
222
Truck
0
1
0
1
3
Bicycle
0
0
0
0
0
Car
Thru
Right
Thru
499
Right
32
Left
Thru
Left
0
Thru
308
Right
44
Total
39
6
Right
112
1
0
0
0
0
7
2
15
0
0
0
0
0
0
0
0
1282
Peak Hour Pedestrians
NE
Pedestrian
s
Left
NW
Right
0
Total
0
Left
0
SW
Right
0
Total
0
Left
0
SE
Right
0
Total
0
Left
0
Right
0
Total
Total
0
0
0
11
Massachusetts
Department
NMCOG
WEEKLY SUMMARY FOR LANE
Starting: 5/9/2011
Site Reference: Rd Class u5
Site ID: 000000007789
Location: Oak Hill Rd S of Rte 40 (Groton Rd)
Direction: ROAD TOTAL
TIME
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
24:00
MON
9
TUE
10
WED
11
THU
12
22
8
13
12
24
113
211
356
347
289
242
282
329
307
369
426
403
446
416
269
202
116
61
34
35
7
8
9
29
100
215
374
394
351
338
320
371
470
412
461
364
272
183
92
75
30
25
9
14
12
31
102
207
353
386
303
275
302
281
297
362
379
409
496
409
265
209
123
58
26
Page:
3
File: oakhi11Srte40.prn
City: Westford
County: 626-2011
FRI
WKDAY
AVG
SAT
SUN
27
8
11
11
28
105
211
361
375
314
258
292
316
308
367
425
408
467
396
268
198
110
64
30
WEEK
AVG
27
8
11
11
28
105
211
361
375
314
258
292
316
308
367
425
408
467
396
268
198
110
64
30
TOTAL
82
24
35
33
84
315
633
1083
1127
943
517
584
948
924
1102
1275
1224
1403
1189
806
594
331
194
90
-------------~---------------------------------------- ---------------------------------------
TOTALS
3388
5333
5297
1522
% AVG WKDY
% AVG WEEK
63.2
63.2
99.5
99.5
98.8
98.8
28.4
28.4
09:00
386
08:00
356
09:00
394
16:00
470
18:00
496
18:00
446
55
14
55
9
55
8
AM Times
AM Peaks
PM Times
PM Peaks
D%
K%
60 26 0
5358
0
0
5358
09:00
375
09:00
375
18:00
467
18:00
467
15540
AWO::- 5/}si'
~(.Jd/j.
­
cE!~
(0.91 )(O.Q8)
tf;B
12
Massachusetts
Department
NMCOG
WEEKLY SUMMARY FOR LANE 1
: 5/9/2011
Site Reference: Rd Class u5
Site ID: 000000007789
Location: Oak Hill Rd S of Rte 40 (Groton Rd)
Direction: NORTH
TIME
MON
9
TOE
10
WED
11
THO
12
4
5
4
8
24
85
157
227
234
188
161
163
140
150
197
177
188
233
201
119
83
40
17
5
8
3
3
11
21
97
160
219
213
181
143
160
185
157
173
199
171
202
188
113
76
41
20
10
6
1
1
7
23
87
158
243
242
210
Page:
1
File: oakhillSrte40.prn
City: Westford
County: 626-2011
FRI
WKDAY
AVG
SAT
SUN
WEEK
AVG
TOTAL
------------------------------------------------------ --------------------------------------01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11 :00
12:00
13: 00
14:00
15:00
16:00
17 :00
18:00
19:00
20:00
21:00
22:00
23:00
24:00
178
174
173
209
190
213
149
116
72
35
24
11
6
3
2
8
22
89
158
229
229
193
152
161
167
160
181
195
183
216
179
116
77
38
20
8
6
3
2
8
22
89
158
229
229
193
152
161
167
160
181
195
183
216
179
116
77
38
20
8
18
9
8
26
68
269
475
689
689
579
304
323
503
481
543
585
549
648
538
348
231
116
61
26
-------------------------------------------~---------------~---------------------------------
TOTALS
1544
2810
2754
978
% AVG WKDY
% AVG WEEK
55.3
55.3
100.6
100.6
98.6
98.6
35
35
09:00
234
08:00
219
08:00
243
18:00
233
18:00
202
AM Times
AM Peaks
PM Times
PM Peaks
18:00
213
0
2792
0
0
2792
08:00
229
08:00
229
18:00
216
18:00
216
8086
13
Massachusetts Highway Department
NMCOG
WEEKLY SUMMARY FOR LANE 2
Starting: 5/9/2011
Site Reference: Rd Class u5
Site ID: 000000007789
Location: Oak Hill Rd S of Rte 40 (Groton Rd)
Direction: SOUTH
TIME
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13: 00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
24:00
9
TUE
10
WED
11
THU
12
14
5
10
1
3
16
51
137
134
108
99
122
144
150
196
227
232
244
228
156
126
75
41
24
29
6
7
2
6
13
57
131
152
141
160
146
198
261
222
248
215
156
111
57
51
19
21
4
10
4
7
17
50
126
152
115
114
139
141
147
165
202
221
263
208
146
126
83
41
21
MON
Page:
2
File: oakhi11Srte40.prn
City: Westford
County: 626-2011
FRI
WKDAY
AVG
SAT
SUN
WEEK
AVG
21
5
9
2
5
15
52
131
146
121
106
130
148
147
186
230
225
251
217
152
121
21
5
9
2
5
15
52
131
146
121
106
130
148
147
186
230
225
251
217
152
121
71
71
44
21
44
21
TOTAL
64
15
27
7
16
46
158
394
438
364
213
261
445
443
559
690
675
755
651
458
363
215
133
64
------------------------------------------------------ --------------------------------------TOTALS
1844
2523
2543
544
% AVG WKDY
% AVG WEEK
72.1
72.1
98.7
98.7
99.4
99.4
21. 2
21.2
09:00
152
08:00
137
09:00
152
18:00
263
18:00
244
AM Times
AM Peaks
PM Times
PM Peaks
16:00
261
0
2556
0
0
2556
09:00
146
09:00
146
18:00
251
18:00
251
7454
14