Road Safety Audit
Washington Street (Route 1)
at May Street
Attleboro,
Massachusetts
Prepared for
10 Park Plaza, Suite 3170
Boston, MA 02116
Prepared by
Transportation, Land Development, Environmental Services
101 Walnut Street
P.O. Box 9151
Watertown, Massachusetts 02472
617 924 1770
December 2009
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Table of Contents
Table of Contents .................................................................................................................... ii Introduction .................................................................................................................................. 2 Study Area and Study Methodology ............................................................................................ 2 Existing Conditions ...................................................................................................................... 3 Assessment ............................................................................................................................... 15 Recommendations ..................................................................................................................... 17 Conclusions ............................................................................................................................... 23 \\Mawatr\ev\10308.00\reports\RSA\RSA_Route1atMayStreet.docx
Introduction
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. Specific objectives of an RSA include, but are not limited to the
following:
•
•
Minimizing the risk and severity of road crashes that may be affected by the
existing or future roadway at a specific location or nearby network;
Improving the awareness of safe design practices which are likely to result in
safety benefits based upon potential safety concerns.
The Massachusetts Department of Transportation (MassDOT) has embraced the RSA
program as a low cost opportunity to make significant safety improvements at any
number of stages ranging from project development and planning through existing
operation.
The RSA program in Massachusetts was initially implemented in accordance with
the Commonwealth's role as a Lead State in preventing run-off the road (lane
departure) crashes and in conjunction with the Strategic Highway Safety Plan
(SHSP). In an effort to combat the lane departure crashes, a strategy was developed
for the SHSP to identify hot spot lane departure locations, perform road safety audits
and implement low-cost comprehensive countermeasures. In 2007, MassDOT
expanded the RSA program to study roadways in which fatal and incapacitating
injury cross median crashes have occurred. MassDOT has now begun to expand the
RSA program to cover hot spot crash intersections and hopes to expand the program
in the future to pedestrian and bicycle hot spot crash locations as well.
Study Area and Study Methodology
The project study area is the intersection Washington Street (Route 1) at May Street in
Attleboro, Massachusetts. This intersection is ranked 82nd in the Top 200 Crash
Locations Report1 for the years 2005-2007. As part of the RSA process a workshop for
the intersection was conducted on Friday, November 20, 2009. This workshop
included an audit team site visit along with pre and post-meetings. Table 1 provides
a list of the participating audit team members.
Table 1
Participating Audit Team Members
Bonnie Polin Name Agency
MassDOT Highway Division Safety Section Lisa Schletzbaum MassDOT Highway Division Safety Section Jason DeGray Vanasse Hangen Brustlin, Inc.
Sgt. Jeffrey Pierce City of Attleboro Police Department
Thomas Rebello MassDOT Highway Division District 5
One Hwang Loubna Saasaa MassDOT Office of Transportation Planning - Public Private
Development Unit
MassDOT Highway Division Safety Section John M Clover City of Attleboro Department of Public Works Bob Araujo City of Attleboro Department of Public Works Deputy Chief J. Scott Jacques City of Attleboro Fire Department
Prior to the RSA field meeting field observations and geometric information were
collected. The information collected included geometric conditions, roadside
features, traffic control devices and signing, intersection visibility/sight distance and
traffic conditions and behaviors of both motorists and non-motorized road users.
Other information used in the RSA included 2008 peak period traffic counts,
operational performance measures (i.e. approach delay, queue lengths) from Synchro
files generated using MassDOT design plans, a crash diagram developed from 2006 –
September 2009 crash reports provided by the City of Attleboro Police Department,
field observations, and digital photos taken during the field review and RSA
meeting.
It should be noted that MassDOT completed an intersection improvement project at
this location in 2006. Available crash data indicates that the frequency of crashes at
this location have significantly been reduced since the completion of this project.
Existing Conditions
The following sections provide a summary of the existing geometric, traffic control
and traffic volume conditions along with crash history of the Washington Street
(Route 1) at May Street intersection.
Geometric Conditions
Washington Street (Route 1) is an urban minor arterial under state jurisdiction
consisting of a four lane, two-way divided (raised concrete median) cross-section in
the vicinity of the intersection. May Street is an urban collector under local
jurisdiction consisting of a two lane, two-way undivided cross-section in the vicinity
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Washington Street (Route 1) at May Street Road Safety Audit
of the intersection. These two roadways intersect to form a four-way, fully actuated
signalized intersection with Washington Street orientated in the north/south
direction and May Street in the east/west direction. Both roadways transition to
additional auxiliary turning lanes at the intersection.
In the summer of 2006 MassDOT completed an intersection improvement project at
this location aimed at enhancing safety and intersection capacity. The improvement
project consisted of upgrading the existing signal equipment and providing exclusive
turning lanes on all approaches. Previously the intersection consisted of two general
purpose lanes in both directions along Washington Street and a single general
purpose lane along both approaches of May Street. As a result, the traffic signal
equipment, pavement, and curbing are currently in excellent condition.
The current lane configuration on each approach is as follows:
•
•
•
•
Northbound approach of Washington Street - 430’ exclusive left-turn lane, a
through lane and a shared through/right-turn lane
Southbound approach of Washington Street - 115’ exclusive left-turn lane, a
through lane and a shared through/right-turn lane
Eastbound approach of May Street - 85’ exclusive left-turn lane, a shared
left/through lane and a 260’ exclusive right-turn lane (extends to the eastern
most Mayfaire Centre driveway)
Westbound approach of May Street - a shared left/through lane and a 70’
exclusive right-turn lane.
Washington Street at May Street Lane Use
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Washington Street (Route 1) at May Street Road Safety Audit
The northbound and southbound left-turn lanes on Washington Street also
accommodate U-turn movements, with the northbound movement aided by a jughandle on the west side of Washington Street. Sidewalks are provided along the
eastbound and westbound approach legs of May Street and the Washington Street
southbound departure. Marked crosswalks are provided across the west and north
legs of the intersection. Land uses in the vicinity of the intersection are primarily
commercial in nature with residential dwellings located to the east and west along
May Street.
A crest vertical curve exists on Washington Street north of the intersection. The crest
of this curve is approximately 1,000 feet north of the intersection with May Street.
While this curve does not impede the sight distance to the signal at May Street (the
required stopping sight distance for the posted 40 mph speed limit is 305’) vehicle
queues in the southbound direction often extend back towards the crest of this curve.
It is possible that this vertical curve may hinder sight distance to the back of queue
during peak hours.
Washington Street (Route 1) north of intersection with May Street
Note the crest vertical curve
There are two unsignalized access points to the commercial property (Mr. Gutter) in
the NW quadrant of the intersection, an entrance only on the northern approach leg
of Washington Street and a full access driveway on the western departure leg of May
Street. These access points are in close proximity to the intersection and are not ideal
from an access management standpoint.
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Washington Street (Route 1) at May Street Road Safety Audit
All approach and departure legs at the intersection include curbing (granite) and
drainage (catch basins). At the time of the RSA (November 2009) the majority of the
catch basins were partially clogged with leaves and other debris.
Figure 1 provides an aerial perspective of the intersection.
Figure 1
Intersection Aerial Photo
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Washington Street (Route 1) at May Street Road Safety Audit
Traffic Control Devices
The intersection operates under fully actuated signal control. The signals on all
approaches are mounted on span wires overhead of the intersection. Signal heads
are 12” LED with back plates. Vehicle and bicycle detection are provided on all
approaches via inductive pavement loops. Vehicle detection is also supplemented
with queue detection loops on all approaches with the exception of the May Street
westbound approach. The Washington Street approaches operate with leading
protected left-turn phasing. The May Street approaches operate with protected split
phasing. The signal is equipped with emergency vehicle preemption via an optical
receiver and warning strobe. Pedestrian LED signal heads (non-countdown) are
provided for both ends of the crosswalks across the western approach of May Street
and the southern approach of Washington Street.
Span Wire and Traffic Signals
Signs posted along the northbound and southbound approaches of Washington
Street consist of “Left Lane Must Turn Left” (R3-7L) and “To Request Green Wait on
Symbol” (R10-22) signs. Signs posted along May Street eastbound consist of “Signal
ahead” (W3-3), two advanced lane control signs (SP-1) and “To Request Green Wait
on Symbol” (R10-22) signs. Signs posted on the May Street westbound approach
consist of “Right Lane Must Turn Right” (R3-7R) and “To Request Green Wait on
Symbol” (R10-22) signs. Other pertinent signs at the intersection include “Stay
Right” (R4-7) signs posted at the median, Route 1 and Route 1A guide signs, “State
Highway Parking Prohibited” (R8-1a Massachusetts Amendment) and a handicap
placard sign posted on the May Street eastbound departure.
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Washington Street (Route 1) at May Street Road Safety Audit
Pavement markings include thermoplastic double yellow center lines (DYCL), single
yellow center lines (SYCL), broken white lane lines (BWLL), single white lane lines
(SWLL), single white edge lines (SWEL), stop bars (SL), Crosswalks (CW), gore lines
(SYGL), lane use control symbol and word markings and bicycle detector pavement
markings.
Traffic Conditions
The speed limit on Washington Street is posted as 40 mph. The speed limit on May
Street is governed by the prima facie speed limit of 30 mph. Traffic counts collected
in July 2007 on Washington Street south of May Street indicated that Washington
Street carried approximately 32,600 vpd2 at that time. Traffic information from the
MassDOT database was also reviewed to determine how volumes may have changed
since that time. According to the MassDOT count station #6023 (Route 1 between
Route 123 Route 1A) the 2007 ADT on Washington Street was 13,600 vehicles per day
(vpd). This is down 2% from the 2004 ADT of 13,900 vpd.
To assess existing traffic conditions in the vicinity of the site, peak hour turning
movement counts (TMC) were obtained from the traffic study of a nearby
development project. These counts were conducted at the intersection on Tuesday,
January 8, 2008 from 4:00 PM to 6:00 PM and on Saturday, January 12, 2008 from
11:00 AM to 2:00 PM. Available MassDOT traffic volume data suggests that January
traffic volumes are approximately 10 percent lower than those observed during the
average month. Therefore, the January traffic volumes were adjusted upward by 10
percent to reflect average month conditions. Figure 2 provides the existing weekday
PM and Saturday midday peak hour volumes.
Figure 2
Existing Peak Hour Volumes
The signal timing and phasing information from the MassDOT design plans for the
intersection are provided in Figure 3.
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Washington Street (Route 1) at May Street Road Safety Audit
Figure 3
Existing Signal Timing and Phasing
Table 2 provides the capacity analysis results for the existing weekday PM and
Saturday midday peak hours based on the volumes in Figure 2 and the signal
phasing and timing in Figure 3.
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Washington Street (Route 1) at May Street Road Safety Audit
Table 2
Washington Street (Route 1) at May Street
Capacity Analysis Summary
Existing Conditions
Period
Movement
V/C
EB LT
0.56
EB R
LOS c
Avgd
95the
56
E
109
280
0.07
49
D
0
54
WB LT
0.76
67
E
153
#271
WB R
0.08
49
D
0
61
NB L/UT
0.76
62
E
180
#297
NB TR
0.67
24
C
413
573
SB L/UT
0.52
57
E
79
133
SB TR
0.91
41
D
616
#781
Overall
0.81
40
D
EB LT
0.65
61
E
145
226
EB R
0.08
51
D
0
57
WB LT
0.66
64
E
125
172
WB R
0.15
54
D
0
40
NB L/UT
0.86
75
E
237
#398
NB TR
0.99
56
E
~871
#1062
SB L/UT
0.60
59
E
124
192
SB TR
1.03
69
E
~834
#976
Overall
0.86
62
E
a
Delay
b
Weekday Evening
May Street
May Street
Washington Street (Route1)
Washington Street (Route1)
Saturday Midday
May Street
May Street
Washington Street (Route1)
Washington Street (Route1)
a
b
c
d
e
~
#
volume to capacity ratio
average delay in seconds per vehicle
level of service
average vehicle queue (feet)
95th percentile queue (feet)
volume exceeds capacity, queue length may be longer
95th percentile volume exceeds capacity
As can be seen in Table 2 the intersection operates at LOS D during the weekday
evening peak period and LOS E during the Saturday midday peak period. Local
authorities have confirmed that the weekend condition is the busiest condition at this
intersection and along Washington Street in general. The intersection signal phasing
and design, having incorporated exclusive turn lanes, left-turn protected only
phasing on Washington Street, split phasing for May Street and long clearance
intervals, clearly are intended to emphasize safety. These measures however do
impact the intersection LOS resulting in the conditions as shown in Table 2. Vehicle
queues on the northbound and southbound approaches of Washington Street do
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Washington Street (Route 1) at May Street Road Safety Audit
extend significantly in both directions during peak hour conditions, particularly
during the Saturday midday peak hour.
Crash Summary
As previously stated this intersection is ranked 82nd in the 2005-2007 Top 200 Crash
Locations Report with a total of 69 accidents occurring over that period. To identify
accident trends and/or roadway deficiencies in the study area, detailed crash reports
for all crashes occurring within the study intersection were obtained from the City of
Attleboro Police Department for the period of January 1, 2006 thru September 2009,
which represent the most recent data available. From this data it was determined that
the total number of accidents which have occurred during the period of 2006-2008
was 38. This data suggests there has been a substantial decrease in the number of
accidents that have occurred at this intersection since MassDOT finished
reconstructing the intersection in the summer of 2006. Through September of 2009
only five accidents have occurred at this intersection for the calendar year.
Figure 4 provides a collision diagram of the City of Attleboro crash data for the
period of January 1, 2006 through September 30, 2009.
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Washington Street (Route 1) at May Street Road Safety Audit
Figure 4
Washington Street at May Street Collision Diagram (2006-September 2009)
Source: City of Attleboro Police Department Crash Records
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Washington Street (Route 1) at May Street Road Safety Audit
The following is a breakdown of the crashes which are included in the Collision
Diagram shown in Figure 4.
A total of 43 crashes were reported within the time period of January 1, 2006 –
September 30, 2009.
•
•
•
•
15 crashes reported in 2006 – 3 crashes construction-related
hazards/confusion
13 crashes reported in 2007
10 crashes reported in 2008
5 crashes in 9 months in 2009
Rear end type crashes account for 25 of the 43 (58%) total crashes
•
•
•
•
9 travelling northbound approaching intersection.
9 travelling southbound approaching intersection.
5 travelling northbound departing intersection (vehicles along Route 1)
No Rear ends were reported on May Street.
Sideswipe type crashes account for 11 of the 43 (26% of total).
A total of 9 crashes occurred within the peak periods of Weekdays 7:00-9:00AM, 4:006:00PM, or Saturday 11:00AM-2:00PM.
•
•
•
•
2006: 0 crashes in AM peak, 1 crash in PM peak, 1 crash in SAT peak.
2007: 0 crashes in AM peak, 5 crashes in PM peak, 0 crashes in SAT peak.
2008: 0 crashes in AM peak, 1 crash in PM peak, 1 crash in SAT peak.
2009: 0 crashes in AM peak, 0 crashes in PM peak, 0 crashes in SAT peak.
22 crashes reported in Daylight and 14 reported after Dark.
Injuries – 7 reported injury crashes – 6 of which were from rear end type crashes on
Route 1.
•
No fatalities reported.
Pavement – 6 crashes reported WET, 2 crashes with SNOW/ICE. - 35 DRY pavement
crashes
A total of 6 crashes involved a vehicle entering the intersection from either approach
on May Street.
•
•
2 Eastbound travelling vehicles taking a Right Turn on Red collided with
Southbound travelling vehicles on Route 1.
1 Westbound travelling vehicle taking a Right Turn on Red collided with a
Northbound travelling vehicle on Route 1.
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Washington Street (Route 1) at May Street Road Safety Audit
The prevailing condition apparent from the crash data is that the majority of the
crashes are of the rear end type. The most cited contributing factors for these crashes
were drivers “being unable to stop in time” for an unspecified reason.
Assessment
The RSA team met the morning of Friday, November 20, 2009 at the City of Attleboro
Fire Station located at 1476 West Street in Attleboro. Following a brief introduction
to the RSA process the audit team discussed safety concerns about the intersection of
Washington Street at May Street. The consensus of all participants was that vehicle
operations and safety at the intersections were significantly improved by the
MassDOT improvement project. Some participants characterized the cause of the
majority of crashes occurring at the intersection post construction as being
attributable to “driver error” and the high volume nature of the intersection. Some
discussion also occurred regarding the possibility that the rear end type crashes on
the northbound departure leg of Washington Street could be attributable to vehicles
turning left into Como Drive approximately 500 feet north of the intersection of
Washington Street at May Street. As these vehicles wait for an acceptable gap in the
southbound traffic flow to execute this maneuver northbound vehicles queue behind
them. The rear-end crashes occur as drivers departing the May Street intersection are
not expecting to stop again so soon. However, based on participant comments the
Mobile Gas Station and Triple Play Car Wash might be greater factors in the nearby
crash experience. Both are located north of the intersection on Washington Street
were noted by participants as creating problematic left-turns.
Following this discussion the audit team visited the intersection to perform an onsite
inspection. The following notes summarize the results/findings of this site visit.
1.
2.
3.
4.
All traffic signal equipment, including pedestrian push buttons and
emergency pre-emption equipment was observed to be functioning properly.
Representatives from MassDOT noted that the westbound approach of May
Street should be signed as “No Turn on Red’ (R10-11b) due to the opposing
double left turns.
While located roughly 350 feet south of the intersection, it was noted that
two pedestrian warning signs (W11-2) posted at the Mayfaire Centre right
turn in/right turn out driveway (one in advance of the driveway, one
beyond the driveway) on Washington Street were incorrectly applied.
During the site visit some participants observed two WB-50 trucks making
simultaneous left-turns from the dual left turn lanes from May Street
eastbound. At the same time a vehicle on May Street westbound was
attempting to turn right onto Washington Street northbound. The outer WB50 had difficulty executing the left-turn and the vehicle on the May Street
westbound had to back up in order for the truck to be able to complete this
maneuver. As a result it was requested that the condition of two large trucks
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Washington Street (Route 1) at May Street Road Safety Audit
(WB-50) turning left simultaneously from the dual left-turn lanes on May
Street eastbound be evaluated to determine if sufficient space is available to
execute these maneuvers.
5. It was noted that the clearance intervals between phases appear to be
excessively long. It was a point of concern that this may be encouraging
road users to effectively extend the green time of each phase because they are
aware of the long clearance interval.
6. It was noted that an existing private business sign appears to be located
within the state highway layout on the departure leg of Washington Street
northbound and may obstruct sight distance.
7. It was suggested that the weeds behind the guard rail on the Washington
Street northbound departure leg of the intersection be maintained as they
appear to be obstructing sight distance.
8. It was recommended that a guide sign be posted on Washington Street
southbound approaching the intersection that reads “May Street next Signal”
(D3-2).
9. It was advised that the existing pavement marking should be monitored and
refreshed on a continual basis. The pavement markings for the existing
crosswalks are currently in need of being reapplied.
10. It was noted that some catch basins were partially to complete clogged with
debris. These drainage features should also be maintained on a continual
basis.
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Washington Street (Route 1) at May Street Road Safety Audit
Recommendations
Following the site visit the audit team returned to the City of Attleboro fire station to
discuss recommendations for the intersection and to conclude the RSA workshop.
Below is a summary of the short and long term recommendations discussed at that
meeting.
Short Term Recommendations
1.
2.
Based on input from the audit team it is
recommended a “No Turn on Red” (R1011b) sign be posted opposite the
westbound approach of May Street. One
of the conditions mentioned in the 2003
version of the MUTCD as guidance for the
utilization of no turn on red signs is if the
geometrics or operational characteristics of the
intersection might result in unexpected
conflicts. In this case the dual left-turn from
May Street eastbound represents an
unexpected condition. It is anticipated that
the sign could be posted on the mast pole
in the northwest quadrant of the
intersection as shown in the picture to the
right.
The two pedestrian warning signs (W11-2)
posted on Washington Street southbound
at the Mayfaire Centre driveway (shown in
the picture to the right) should be
removed. The W11-2 sign is intended to
alert road users in advance of locations
where unexpected entries into the roadway
by pedestrians might occur. It is not
intended to warn road users of pedestrians
crossing an intersecting side street or
driveway. Furthermore the sign beyond
the driveway is facing away from
oncoming traffic making its application
even more confusing. While both of these
signs should be removed, the sign in
advance of the driveway could be replaced
by a “Turing Traffic Yield to Pedestrians
Sign” warning sign.
May Street Westbound – “No Turn on Red”
Mayfaire Centre Driveway Pedestrian Warning Signs
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Washington Street (Route 1) at May Street Road Safety Audit
3.
As requested by the audit team VHB
assessed the existing clearance intervals at
the intersection. Based on this evaluation it
appears that the clearance intervals could
be slightly reduced. See the table to the
right for the existing clearance interval and
the VHB recommended clearance interval
by approach. Detailed calculations are
contained in the appendix. A reduction in
the clearance interval would need official
approval from the State Traffic Engineer
through the permitting process before it
can be implemented.
Washington Street
Northbound Left
Washington Street
Northbound Thru
Washington Street
Southbound Left
Washington Street
Southbound Thru
May Street
Eastbound
May Street
Westbound
Y
4
Existing
R
T
3
7
Y
4
∆
-1
4
3
7
4
2
6
-1
4
3
7
4
2
6
-1
4
3
7
4
2
6
-1
3.2
3.3
6.5
3
3
6
-0.5
3.2
3.3
6.5
3
3
6
-0.5
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VHB
R
T
2
6
Washington Street (Route 1) at May Street Road Safety Audit
4.
The existing private business sign
(Chemawa Golf Course) noted during the
RSA site visit has been confirmed to be
located within the state highway layout on
the northbound departure leg of
Washington Street. Furthermore this sign
was noted for removal in the final design
plans for the recently completed MassDOT
improvement project at this intersection. It
is unclear why this sign was not removed.
The permit section of MassDOT – Highway
Division District 5 will notify Chemawa
Golf Course that their sign should be
removed.
Chemawa Golf Course Sign
Construction Plan indicating Removal of Chemawa Sign
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Washington Street (Route 1) at May Street Road Safety Audit
5.
Pavement markings should be refreshed
and catch basins should be cleaned on a
continual basis. Some catch basins are
currently in need of cleaning. Existing
crosswalk markings are in need of being
reapplied.
Partially Worn Pavement Markings
Catch Basin in need of Cleaning
6.
An advanced street name sign (D3-2)
should be posted on the southbound
approach of Washington Street. The
MUTDC provides guidance for the use of
this type of sign: Advance Street Name (D32) signs may be installed in advance of
signalized or unsignalized intersections to
provide road users with advance information to
identify the name(s) of the next intersecting
street to prepare for crossing traffic and to
facilitate timely deceleration and/or lane
changing in preparation for a turn. Right-ofway constraints may limit the placement of
this sign.
Proposed May Street Advance Street Name Sign (D3-2)
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Washington Street (Route 1) at May Street Road Safety Audit
Long Term Recommendations
1.
A concern was expressed by the audit team that two large trucks (WB-50) turning left simultaneously
from the dual left-turn lanes on May Street eastbound may not have sufficient space available to
execute these maneuvers. It should be noted that design guidance for dual left turn lanes is typically
to design for a WB-50 truck in the outer left-turn lane and a SU truck in the inner left-turn lane
turning simultaneously. As shown in Figure A-1 in the appendix this condition is satisfied. For the
condition of dual WB-50 trucks turning simultaneously the inner truck would be unable to execute
this maneuver without encroaching upon the nose of the center median. In order to accommodate
these dual left-turn movements the center median and stop bar would need to be pulled back (~22’)
from the intersection. The segment of island removed should be replaced with a scored concrete
center median. Figure A-2 in the appendix and the picture to the right show this condition. It should
be noted that the frequency of two WB-50’s simultaneously turning left is very small, and there are
disadvantages associated with moving the stop bar, such as longer clearance intervals and pedestrian
crossing distance.
Dual WB-50 Left Turns from May Street
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Washington Street (Route 1) at May Street Road Safety Audit
2.
As noted in the crash diagram, a significant number of rear-end crashes occur in the northbound
direction as vehicles depart the Washington Street at May Street intersection. The cause of these
crashes in not immediately clear. RSA participants identified a number of possible causes, including
turning movements associated with the existing Mobile Gas Station and the Triple Play Car Wash
and vehicles turning left from the northbound direction onto Como Drive. In order to definitively
state the contributing factors of these crashes (and to design appropriate countermeasures) the
Attleboro Police Department should note which lane the crash occurs in and the probable cause in the
crash report.
If it is determined that left-turns to Como Drive are a significant contributing factor to the rear end
crashes on the departure leg of Washington Street northbound, consideration should be given to
extending the raised center median north beyond Como Drive. This would eliminate the possibility
of northbound vehicles on Washington Street getting stuck behind left-turning vehicles and having to
unexpectedly stop so soon after departing the May Street intersection. It should be noted that rightof-way and environmental issues prohibited the extension of this median during the 2006
reconstruction of the Washington Street (Route 1) at May Street intersection.
Extend Median to eliminate Left-turns at Como Drive
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Washington Street (Route 1) at May Street Road Safety Audit
Conclusions
The measures that can be expected to enhance safety at the intersection have been
described in this report. Although the intersection of Washington Street (Route 1)
and May Street is ranked 82nd on the most recent top 200 crash locations report, the
safety review of this intersection indicates that the most severe problems at this
intersection have been corrected by the recently completed MassDOT intersection
improvements project. It is anticipated that in future years as the top 200 crash
locations reports are updated with crash data post 2006 the intersection will continue
to move further down the list, if not off the list completely, based solely on the
improvements made as part of this project. However, a number of safety items have
been identified through the data analysis and the RSA workshop field observations;
and, potential treatments have been suggested for consideration. A number of these
items included improvements regarding signage, including eliminating the right turn
on red on the May Street westbound approach, and pavement markings. In addition,
long term improvements to the intersection would be to modify the southbound
approach of Washington Street and the raised center island to accommodate
simultaneous large truck (WB-50) left turn movements and, while removed from the
intersection, to extend the raised center median along Washington Street north of the
intersection beyond Como Drive to eliminate left-turns if warranted at this location.
\\Mawatr\ev\10308.00\reports\RSA\RSA_Route1atMayStreet.docx
23
Washington Street (Route 1) at May Street Road Safety Audit
Appendix
Road Safety Audit Agenda
2007 High Accident Location Report Excerpts
Washington Street (Route 1) Speed Regulation
Turning Movement Counts
Washington Street (Route 1) and May Street Final MassDOT Traffic Signal
Design Plans
Intersection Capacity Reports
May Street Eastbound Simultaneous Left Turn Truck Movements
Washington Street (Route 1) and May Street Clearance Time Calculations
\\Mawatr\ev\10308.00\reports\RSA\RSA_Route1atMayStreet.docx
Appendix
Road Safety Audit Agenda
\\Mawatr\ev\10308.00\reports\RSA\RSA_Route1atMayStreet.docx
Appendix
Road Safety Audit
Attleboro – Washington Street (Route 1) at
May Street
Meeting Location: South Attleboro Fire Station
1476 West Street
Friday, November 20, 2009
10:00 AM – Noon
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
10:15 AM
Review of Site Specific Material
• Crash, Speed & Volume Summaries– provided in advance
• Existing Geometries and Conditions
10:45 AM
Visit the Site
• Drive to the intersection
• As a group, identify areas for improvement
11:45 AM
Post Visit Discussion / Completion of RSA
• Discuss observations and finalize findings
• Discuss potential improvements and finalize recommendations
12:00 noon
Adjourn for the Day – but the RSA has not ended
Instructions for Participants:
• Before attending the RSA on November 20th, participants are encouraged to drive
through Washington Street (Route 1)/May Street 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.
2007 High Accident Location Report Excerpts
\\Mawatr\ev\10308.00\reports\RSA\RSA_Route1atMayStreet.docx
Appendix
TOP HIGH CRASH LOCATIONS REPORT
Top 200 Intersection Locations 2005-2007
Top Pedestrian Locations 2002-2007
Top Bicycle Locations 2002-2007
Introduction
MassHighway obtains crash data from the Massachusetts Registry of Motor Vehicles (RMV) and uses it
for a number of purposes. The primary function, however, is that it provides the foundation for
developing safety improvement projects. The Top High Crash Locations Report is one of the tools used
in this process. Previously, MassHighway, with the assistance from Central Transportation Planning
Staff (CTPS), produced a Top 1000 Highway Crash Locations Report which included all types of
locations (interchanges, intersections and rotaries). Two years ago, MassHighway developed a new
report type where the locations identified were crash clusters at intersections (no grade separated locations
and no locations with weaving sections). Beginning last year, the report also included the top bicycle and
pedestrian clusters. This year, MassHighway has also prepared a Top High Crash Locations Report
which includes the top 200 high crash intersection locations using crash data from 2005-2007 and also
includes the highest frequency bicycle-motor vehicle and pedestrian-motor vehicle crash locations for
2002-2007.
The Registry of Motor Vehicles (RMV) obtains crash data from State and local police reports and from
motor vehicle operators (motorists) who are involved in crashes. The RMV Crash Records Section
collects, enters and maintains crash data records, which are the source of the MassHighway crash data.
To produce this high crash locations listing, MassHighway, with the assistance of Geonetics, has
developed an automated procedure for processing, standardizing, matching and aggregating the crash data
by geographical location using Geographic Information System (GIS) tools and procedures.
Generally, the geocoding rate (the rate at which crashes can be located to a specific geographical point)
for crashes between 2005 and 2007 is nearly 81%. However, the geocoding rate is not uniform for all
crashes nor for all types of crash locations. Some crashes may be more difficult to geocode because of
multiple intersections between the same roadway names within a community, inconsistencies in roadway
names between E911 files and the Road Inventory File or a host of other reasons.
Furthermore, the reporting levels of some communities have changed dramatically between the old
reporting format (pre-2002) and the new format. As an example, one community has dropped reporting
levels by nearly a factor of 10, while another community has dramatically increased their reporting levels
so that they are now reporting nearly 10 times the number of crashes. Obviously, these reporting changes
significantly impact the results of the Top High Crash Locations Report.
Due to the many difficulties in obtaining precise, useable crash location data and many issues involved in
variations in crash reporting rates by some jurisdictions, this report should be used as a general purpose
screening tool rather than as a precise listing of crash frequencies by individual locations. Furthermore,
because of the spatial nature of the crash clusters, it is imperative to view the crash clusters spatially and
not just rely on the tabular naming convention to understand the crash cluster locations.
Methodology – Intersection Locations
The intersection crash cluster analysis method, developed by Geonetics, is a comprehensive method
designed to locate crash clusters. At the heart of the method is a 25 meter fixed search distance around
each crash. In basic terms, this radius controls how far the application will search for adjacent crashes.
i
Using a 25 meter radius, the analysis method found nearby crashes and merged their areas together, thus
creating clusters. If two distinct clusters are found to share a common crash, the two clusters are merged
into a single cluster. This method of search-and-merge results in a set of many distinct clusters of
different sizes and shapes The application then stores these clusters to the GIS output file, along with the
count of crashes within the cluster. The clusters were then ranked by the number of Equivalent Property
Damage Only (EPDO) crashes contained within their boundaries. As in previous Top Crash Lists, fatal
crashes are weighted by 10, injury crashes are weighted by 5 and property damage only or non-reported is
weighted by 1. These are the same weights that were used to generate the previous Top 1000 High Crash
Locations Report using crash data from the previous crash system.
The crashes were then named based on the highest functional classification roadway within the cluster,
followed by the roadway with the second highest functional classification. In instances where there were
two roadways with the identical classification, the first street name selected was the street with the longest
segment contained within the cluster. Some cluster naming was modified to insert the name of a private
way or site drive, rather than leaving it as unnamed. Note that the area encompassing the crash cluster
may cover a larger area than just the intersection.
The module to automatically determine whether the location was an intersection, rotary, interchange or
other, has not yet been developed. Therefore, a review of each location was required to make that
determination. Generally, a location was determined to be an “intersection” if the cluster did not contain
roadways with grade separation (interchange) nor weaving sections (rotaries or ramps). The clusters were
reviewed in descending EPDO order until 200 locations were obtained. A sample of the top 2 ranked
intersection locations is included in this report to illustrate the concept of the intersection clustering. The
actual crash clusters can be viewed on the interactive maps at mass.gov/mhd/topcrashclusters.
Furthermore, a shape file of the top crash intersection locations is available upon request.
The above method was used to develop the top 200 intersection crash locations for crashes occurring
during the three year period from 2005 to 2007. As with previous editions, the crash location analysis has
been scored over a three-year period. By using crash experience over the three-year period, anomalies in
the individual years of data tend to be reduced.
Methodology – Pedestrian and Bicycle Locations
Similar to last year, the top locations where reported collisions occurred between pedestrians and motor
vehicles and bicycles and motor vehicles have been identified. The crash cluster analysis methodology
for both the top pedestrian and the top bicycle crashes is similar to the top intersection location
methodology in that it uses a fixed meter search distance (for both pedestrian and bicycle crashes it is 100
meters compared to 25 meters for intersection locations) to merge crash clusters together. Crashes
involving collisions between motor vehicles and pedestrians or bicycles were identified by using the nonmotorist type code within the CDS database (which may yield different results from using most harmful
event, first harmful event, or sequence of events data fields). Furthermore, the methodology uses the
Equivalent Property Damage Only (EPDO) weighting to rank the clusters. However, because of the
relatively small number of reported pedestrian and bicycle crashes in the crash data file, the clustering
analysis used crashes from the six year period from 2002-2007, instead of the three year analysis for
intersection locations. Additionally, due to the larger geographic area encompassed by both the
pedestrian and the bicycle crash clusters, it was difficult to name them so they were left unnamed but can
be viewed spatially. The top 10 ranked pedestrian crash locations and the top 10 bicycle crash locations
are included in this report. The actual crash clusters can be viewed on the interactive maps at
mass.gov/mhd/topcrashclusters.
ii
For further information, please contact Neil Boudreau, State Traffic Engineer, Traffic Engineering
Section, Massachusetts Highway Department, 10 Park Plaza, Room 7210, Boston, MA 02116, phone
(617) 973-8211.
NOTICE
It should be noted that the Top 200 High Crash Intersection Locations Report
was compiled under the authority of United States Code Title 23, Section 148,
Highway Safety Improvement Program, sponsored by the Federal Highway
Administration. The compilation of such information is, therefore, subject to
the limitations of Section 148 (g) (4) which states:
“Discovery and admission into evidence of certain reports, surveys, and
information - Notwithstanding any other provision of law, reports, surveys,
schedules, lists, or data compiled or collected for any purpose directly relating
to paragraph (1) or subsection (c)(1)(D), or published by the Secretary in
accordance with paragraph (3), shall not be subject to discovery or admitted
into evidence in a Federal or State court proceeding or considered for other
purposes in any action for damages arising from any occurrence at a location
identified or addressed in such reports, surveys, schedules, lists, or other
data.”
iii
5/11/2009
6
1
9
202
3A
138
9
110
9
125
2A
3A
9
9
28
9
97
1
203
53
18
202
125
27
114
138
135
16
20
203
9
16
3A
Route 2
28
203
97
53
203
14
16
114
123
187
PDO & Non Reported Crashes
107
105
126
21
60
99
Injury Crashes
135
60
107
3
9
113
Fatal Crashes
97
125
123
60
SEYMOUR STREET
WELLESLEY FIRE STATION HEADQUARTERS (BY PROXIMITY)
MAY STREET
JOYCE STREET
BAILEY BOULEVARD
WATER STREET
LINWOOD STREET
MAPLEWOOD STREET
DORCHESTER AVENUE
SPEEN STREET
BROADWAY
CHATHAM STREET
RIVER STREET
LYMAN STREET
MASSACHUSETTS AVENUE
CENTRE STREET
EAST GROVE STREET
HARTFORD STREET
CHERRY STREET
COMMERCIAL STREET
EAST ASHLAND STREET
SWANSEA MALL DRIVE
MAY STREET
PLEASANT STREET
LAKE AVENUE NORTH
GALLIVAN BOULEVARD
POCHASSIC STREET
WINN STREET
BRADFORD AVENUE
MAIN STREET
INDUSTRIAL AVENUE
LANCASTER STREET
JACKSON STREET
WINTER STREET
BROOKLINE STREET
SOUTHERN ARTERY
HIGHLAND STREET
CHESTNUT HILL AVENUE
LUMBER STREET
MORTON STREET
WEST OBERLIN STREET
BROADWAY
CHESTNUT STREET
GALLIVAN BOULEVARD
COMMERCIAL STREET
AUBURN STREET
LOCKHOUSE ROAD
ALEWIFE BROOK PARKWAY
MASSACHUSETTS AVENUE
CHATHAM STREET
WARREN AVENUE
ANDOVER STREET
WASHINGTON STREET
BEAVER STREET
LEGION PARKWAY
HAMMOND STREET
WATERTOWN STREET
LITTLE RIVER ROAD
HARVARD STREET
PARKER STREET
GARFIELD AVENUE
WILDER STREET
EPDO Crashes
9
9
Total Crashes
LINDEN STREET
WORCESTER STREET
PARK AVENUE
ESSEX STREET
MAIN STREET
BRIDGE STREET
BELMONT STREET
EASTERN AVENUE
COLUMBIA ROAD
WEST CENTRAL STREET
EASTERN AVENUE
WESTERN AVENUE
MEMORIAL DRIVE
BOSTON WORCESTER TURNPIKE
COLUMBIA ROAD
WESTERN AVENUE
SOUTH MAIN STREET
CONCORD STREET
CENTER STREET
CENTRE STREET
NORTH MAIN STREET
GRAND ARMY OF THE REPUBLIC HIGHWAY
WASHINGTON STREET
UNION STREET
BELMONT STREET
DORCHESTER AVENUE
NORTH ELM STREET
CAMBRIDGE STREET
BROADWAY
HIGHLAND STREET
CHELMSFORD STREET
HIGHLAND STREET
MAIN STREET
MAIN STREET
MASSACHUSETTS AVENUE
WASHINGTON STREET
PARK AVENUE
BOYLSTON STREET
WEST MAIN STREET
BLUE HILL AVENUE
PARK AVENUE
LAFAYETTE SQUARE
EAST WASHINGTON STREET
MORTON STREET
WASHINGTON STREET
BEDFORD STREET
NORTH ELM STREET
BROADWAY
CHICKERING ROAD
ESSEX STREET
PLEASANT STREET
PULASKI STREET
BROADWAY
WAVERLEY STREET
MAIN STREET
SOUTHBRIDGE STREET
GALEN STREET
EAST MAIN STREET
MORTON STREET
PARK AVENUE
REVERE BEACH PARKWAY
WESTFORD STREET
Street 2
1
4
3
4
4
4
5
4
4
3
4
4
4
3
4
4
5
3
2
4
5
5
5
4
3
4
2
4
5
3
4
3
2
4
4
4
3
4
3
4
3
4
5
4
4
5
2
4
4
4
5
4
5
3
5
3
4
2
4
3
4
4
Route 1
BRPC
MAPC
CMRPC
MAPC
MVPC
MVPC
OCPC
MAPC
MAPC
MAPC
MAPC
MAPC
MAPC
CMRPC
MAPC
MAPC
SRPEDD
MAPC
PVPC
MAPC
OCPC
SRPEDD
SRPEDD
MAPC
CMRPC
MAPC
PVPC
MAPC
SRPEDD
CMRPC
NMCOG
CMRPC
PVPC
MVPC
MAPC
MAPC
CMRPC
MAPC
MAPC
MAPC
CMRPC
MVPC
SRPEDD
MAPC
MAPC
OCPC
PVPC
MAPC
MVPC
MAPC
OCPC
MAPC
SRPEDD
MAPC
OCPC
CMRPC
MAPC
PVPC
MAPC
CMRPC
MAPC
NMCOG
Street 1
PITTSFIELD
WELLESLEY
WORCESTER
LYNN
HAVERHILL
HAVERHILL
BROCKTON
MALDEN
BOSTON
NATICK
MALDEN
LYNN
CAMBRIDGE
WESTBOROUGH
BOSTON
LYNN
MIDDLEBOROUGH
FRAMINGHAM
LUDLOW
MALDEN
BROCKTON
SWANSEA
ATTLEBORO
WEYMOUTH
WORCESTER
BOSTON
WESTFIELD
BURLINGTON
FALL RIVER
WORCESTER
LOWELL
WORCESTER
HOLYOKE
HAVERHILL
CAMBRIDGE
QUINCY
WORCESTER
BROOKLINE
HOPKINTON
BOSTON
WORCESTER
HAVERHILL
NORTH ATTLEBOROUGH
BOSTON
WEYMOUTH,BRAINTREE
WHITMAN
WESTFIELD
SOMERVILLE
NORTH ANDOVER
LYNN
BROCKTON
PEABODY
TAUNTON
FRAMINGHAM
BROCKTON
WORCESTER
WATERTOWN
WESTFIELD
BOSTON
WORCESTER
CHELSEA
LOWELL
MHD District
Town
63
63
65
65
65
68
68
70
71
72
72
74
75
75
75
78
79
79
79
82
82
82
82
82
82
88
88
88
91
91
91
94
94
94
94
94
94
94
101
102
103
104
105
105
105
105
109
109
111
111
113
114
114
116
116
116
119
119
119
119
119
124
RPA
Rank
2005-2007 STATEWIDE TOP 200 INTERSECTION CRASH LIST
54
110
77
65
73
80
56
59
57
101
73
64
66
78
58
67
86
62
70
53
57
73
69
101
65
52
88
84
75
71
71
54
54
78
70
82
78
54
73
56
67
82
52
45
85
49
44
72
59
71
54
61
53
76
52
56
54
51
51
63
55
58
158
158
157
157
157
156
156
155
154
153
153
152
150
150
150
147
146
146
146
145
145
145
145
145
145
144
144
144
143
143
143
142
142
142
142
142
142
142
141
140
139
138
137
137
137
137
136
136
135
135
134
133
133
132
132
132
131
131
131
131
131
130
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
26
12
20
23
21
19
25
24
22
13
20
22
21
18
23
20
15
21
19
23
22
18
19
11
20
23
14
15
17
18
18
22
22
16
18
15
16
22
17
21
18
14
19
23
13
17
23
16
19
16
20
18
20
14
20
19
17
20
20
17
19
18
28
98
57
42
52
61
31
35
34
88
53
42
45
60
35
47
71
41
51
30
35
55
50
90
45
29
74
69
58
53
53
32
32
62
52
67
62
32
56
35
49
68
32
22
72
42
21
56
40
55
34
43
33
62
32
37
36
31
31
46
36
40
Page 2 of 4
Washington Street (Route 1) Speed Regulation
\\Mawatr\ev\10308.00\reports\RSA\RSA_Route1atMayStreet.docx
Appendix