Lane
e Departure Road
R
S
Safety
Audit for
Interrstate 290
2 thrrough Worce
ester, Massa
M
etts
chuse
Prrepared by
Ce
entral Mass
sachusetts Regional
R
Pllanning Com
mmission
and
Unive
ersity of Mas
ssachusetts Traffic Sa
afety Research Program
m
Prrepared for
Massachus
setts Highw
way Departm
ment
Federal Hig
ghway Adm
ministration
1.0 Introduction to Road Safety Audits & Lane Departure Crashes in Massachusetts
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.
Although RSA’s have been employed in other countries for some time, they are being fully embraced
across the United States as a low cost opportunity to make significant safety improvements at any
number of stages ranging from project development and planning through existing operation.
Furthermore, RSA’s have proven to be effective on projects of all shapes and sizes. The RSA program
here in the Commonwealth presents a unique and exciting opportunity for improvements in roadway
safety.
The RSA program in Massachusetts is being 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). Lane departure crashes are a notable problem area for
Massachusetts, especially for crashes with high injury severities. Between 2002 and 2004, lane
departure crashes accounted for nearly 20 percent of all crashes in Massachusetts and approximately
one-quarter of crashes involving an incapacitating injury. Almost one-half of fatal crashes between
2002 and 2004 were lane departure crashes. As the crash severity increases, so too does the percent of
crashes that is lane departures as shown in Figure 1.
All Massachusetts Crashes,
2002-2004
Massachusetts Incapacitating
Injury Crashes, 2002-2004
18.7%
Lane Departure Crashes
Massachusetts Fatal Crashes, 20022004
24.5%
46.2%
Other Crashes
Figure 1 Relationship between Lane Departure Crashes and Injury Severity
In an effort to combat the lane departure problem, a strategy was developed for the SHSP to identify
hot spot lane departure locations, perform road safety audits and implement low-cost comprehensive
countermeasures. The following report summarizes the findings of a RSA focused on lane departure
crashes (LD-RSA) along Interstate 290 (I-290) through Worcester, Massachusetts.
Page 2
2.0 Background Material for Interstate 290
I-290 is a 20 mile segment of highway that stretches from Auburn, Massachusetts to Marlborough,
Massachusetts. I-290 connects the Massachusetts Turnpike (I- 90) through downtown Worcester,
Massachusetts and bends east towards Marlborough, Massachusetts before ending at Interstate 495.
Worcester is the second largest city in New England, located in Worcester County, with a population
estimated to be over 175,000 in 2006. Within
Worcester, I-290 extends approximately 7 miles and
has 12 exits which provide access to facilities such as
the
Worcester
Regional
Airport,
the
Amtrak/Commuter Rail Station, local colleges, and
other major roads (Interstates and state routes). Three
of the twelve exits are westbound exit/eastbound
entrance only, three are eastbound exit/westbound
entrance only, and one has no westbound entrance.
The cross section for I-290 varies from three up to a
maximum of five lanes in each direction at various
points as it passes through downtown Worcester. A
sample cross-section for I-290 is shown in Figure 2,
and
a summary of major characteristics, including
Figure 2 Interstate 290 in Worcester
crash summaries, is presented in Figure 3.
The LD-RSA for I-290 was held on November 28, 2007 at the CMRPC offices in Worcester,
Massachusetts. In total, 12 team members participated in the road safety audit as listed in Table 1, and
as indicated representatives were present from Federal, State, Regional and Local agencies including a
cross-section of engineering/planning, education, and enforcement expertise. Members of the lane
departure road safety audit team were encouraged to visit I-290 prior to the meeting to familiarize
themselves with the roadway attributes and characteristics. A copy of the meeting agenda and
instructions, as well as a packet of pertinent information was distributed to RSA meeting invitees prior
to the meeting; this information is included in the Appendix of this report.
Table 1 Participating Audit Team Members
Audit Team Members
Bonnie Polin
Neil Boudreau
One Hwang
Agency/Affiliation
Massachusetts Highway Department – Safety Management Unit
Massachusetts Highway Department – Traffic Engineering Section
Massachusetts Highway Department – Highway Design
Lisa Schletzbaum
Massachusetts Highway Department – Safety Management Unit
Sylvia Hertl
Massachusetts Highway Department – Safety Management Unit
Tim White
Federal Highway Administration
Ken Petraglia
Beta Group, Inc.
Mark Johnson
Massachusetts Highway Department – District 3 Traffic Engineering
Joe Frawley
Massachusetts Highway Department – District 3 Traffic Engineering
Dan Nicoloro
Massachusetts State Police
Kevin Krasnecky
Central Massachusetts Regional Planning Commission
Michael Knodler
University of Massachusetts – Amherst
Page 3
In WB direction the area
after the merge with I-190
becomes 5 lanes prior to a
middle lane drop
Combined horizontal
and vertical curve
East toward I-495
Dual exit 19 & 20
in EB direction
Vertical curve (downgrade EB)
with fairly straight alignment
ATR Location #3
Sept. 2007
Core area of downtown
Worcester which is
serviced by a series of
closely spaced
interchanges, including
exits 13, 14, 15, and 16
ATR Location #2
Aug. 2007
Cluster of lane departure
crashes. Tangent section
of roadway following /
leading curves with in an
area with limited concrete
median or roadside barriers
ATR Location #1
Sept. 2007
Horizontal curve with
enhanced delineation
Southwest to
Auburn and
MassPike (I-90)
As may be expected there is a
high level of adjacent
development and visual activity
throughout the corridor
Figure 3 Major Characteristics for Interstate 290 through Worcester
Page 4
Additional information regarding crashes, volumes, and speed limits were summarized during the
course of the meeting as follows.
•
Massachusetts Highway Department (MassHighway) traffic count data was provided for both the
eastbound and westbound directions from three different ATR studies, which are summarized in
Table 2. As shown the ADT varies from the core of downtown Worcester as compared to the
study location just south of downtown. Through downtown the ADT exceeds 125,000, with a
slightly higher eastbound volume. During peak periods there are over 10,000 vehicles on I-290.
Table 2 Summary of Observed Traffic Volumes along Route 24
Interval
Start time
12:00 AM
ATR Location #1
I-290 North of Hope Ave.
September 2007
EB
WB
TOTAL
370
365
735
ATR Location #2
I-290 at East Central Street
August 2007
EB
WB
TOTAL
618
635
1253
ATR Location #3
I-290 at Lincoln Street
September 2007
EB
WB
TOTAL
483
450
933
1:00 AM
281
258
539
404
361
765
325
301
626
2:00 AM
290
212
502
360
337
697
316
259
575
3:00 AM
344
196
540
386
311
697
389
271
660
4:00 AM
595
311
906
770
384
1154
792
407
1199
5:00 AM
1430
704
2134
1813
1048
2861
1857
1063
2920
6:00 AM
3862
1406
5268
4074
2300
6374
4405
2698
7103
7:00 AM
4823
1870
6693
5265
3301
8566
5627
4808
10435
8:00 AM
4048
1814
5862
4782
3138
7920
4609
4451
9060
9:00 AM
2877
1947
4824
3625
3232
6857
3305
3628
6933
10:00 AM
2588
1906
4494
3373
3367
6740
3258
3084
6342
11:00 AM
2353
2004
4357
3341
3401
6742
3174
3078
6252
12:00 PM
2427
2172
4599
3449
3358
6807
3402
3254
6656
1:00 PM
2570
2221
4791
3573
3405
6978
3503
3499
7002
2:00 PM
2874
2654
5528
3965
4056
8021
4251
3929
8180
3:00 PM
3153
3167
6320
4009
4850
8859
4649
4190
8839
4:00 PM
2922
3555
6477
4248
5105
9353
4643
4263
8906
5:00 PM
3158
3455
6613
4216
5115
9331
4555
4279
8834
6:00 PM
2538
2284
4822
3484
3837
7321
3493
3625
7118
7:00 PM
1913
1896
3809
2721
3272
5993
2636
2728
5364
8:00 PM
1547
1549
3096
2426
2758
5184
2206
2172
4378
9:00 PM
1418
1313
2731
2173
2207
4380
2047
1980
4027
10:00 PM
1025
841
1866
1581
1678
3259
1342
1283
2625
11:00 PM
731
721
1452
1087
1297
2384
924
1007
1931
Daily
Totals
50137
38821
88958
65743
62753
128496
66191
60707
126898
Page 5
•
Observed travel speeds and speed limits are a concern on along I-290. On either side of
Worcester, I-290 is posted at 65 mph, with actual travel speeds likely in excess of that value
based upon anecdotal accounts of RSA team members present; however through the existing
curvature and the core of downtown Worcester, the posted speed limit is 50 mph. This
reduction, as well as driver’s recognition of it, and adherence to it, is discussed in greater detail
later in this report. The actual speed regulations for I-290 through Worcester are summarized
in Table 3.
Table 2 Summary of Speed Regulations for I-290 in Worcester
Eastbound
Westbound
Beginning at the Auburn line
Beginning at the Shrewsbury line
0.51 miles
at 65 mph
1.45 miles
at 65 mph
4.87 miles
at 50 mph
4.88 miles
at 50 mph
1.46 miles
at 65 mph
0.51 miles
at 65 mph
Ending at the Shrewsbury line
Ending at the Auburn line
•
MassHighway compiled, and distributed I-290 crash data. There were 371 reported crashes
along I-290 in Worcester between 2005 and 2007. Of these crashes, 29 percent (109 crashes)
were lane departure crashes (plotted in Figure 3), and 6 percent were work zone crashes; the
frequency of work zone crashes is not surprising given both the magnitude and duration of
construction along this corridor. A comprehensive summary of the 371 crashes is included
within the Appendix; however, some of the key observations include the following:
o 65 percent of all crashes occurred during daylight conditions, and 26 percent occurred at
night. By comparison, 51 percent of lane departure crashes occurred at night.
o Considering all crashes, the predominant crash pattern was rear-end crashes (48
percent) followed by single vehicle crashes (25 percent), and sideswipes in the same
direction (17 percent). 94 percent of the lane departure crashes involved a single
vehicle.
o For lane departure crashes, 36 and 26 percent of crashes involved a median barrier or
guard rail, respectively.
o Lane departure crashes tended to be more severe as 60 percent involved an injury (59
percent) or fatality (1 percent). Amongst all crashes, 30 percent involved an injury (29
percent) or fatality (1 percent).
o A variety of driver contributing codes were included for lane departure crashes: failure
to keep proper lane (26 percent), driving too fast for conditions (17 percent), exceeding
authorized speed limit (13 percent), operating vehicle in erratic, reckless, careless
manner (9 percent), over correcting / over-steering (7 percent), and unknown or not
reported (18 percent).
Additional resources made available to the team during the audit meeting included field videos from
several drives along I-290 which were used in aiding discussion of specific roadway elements. Also
available were possible resources including the AASHTO Strategic Highway Safety Plan and the
related National Cooperative Highway Research Program (NCHRP) 500 series reports.
Page 6
3.0 Characterization of Major Traffic Safety Challenges
Following a brief introduction to the RSA process in general, the meeting participants were asked to
summarize and characterize potential safety considerations along I-290 through Worcester. The initial
characterization of the major safety considerations focused on several key elements.
•
•
•
•
•
•
•
An initial topic of conversation was related to speeds throughout the corridor. Of specific
concern was the reduction in speed (65 to 50 mph) that occurs on both ends of this segment.
The Massachusetts State Police had sent a letter requesting enhanced signage or other measures
which would alert drivers to the speed reduction. These sentiments were echoed by many of the
RSA team members in attendance. Coupled with this concern over reductions were the
anecdotal reports of off-peak speeds which were reported in the range of 80 to 85 mph.
A second major concern in the westbound direction was the overall 5-lane cross-section and
merging / weaving once I-190 joins in to I-290. Specifically cited was the wide cross-section
with worn pavement markings, as well as the fact that the downstream lane drop is a merge of
two middle lanes. Also noted was the perceived panic which some drivers experience resulting
in drivers attempting to move right, immediately after the merge occurs to access the next
downstream exit.
The existing work zones and construction, which have been ongoing for some time, were
discussed; however, it was reported that major construction is scheduled for completion in the
spring of 2008.
Traffic spills back on to I-290 from some of the exit ramps. The safety concern was attributed
to the adjacent surface intersections that were not equipped to process the existing traffic. A
specific example mentioned was Exit 18 where an intersection two blocks from the interchange
(Salisbury Street) queues enough to impede the exiting right-turn traffic from I-290.
The traveling conditions along I-290 vary considerably
throughout the course of the day and across days of the week.
This is particularly true in light of the current construction and
associated work zones. Some concern was raised about how
this information is related to drivers. It is relevant to note that
there are overhead variable message signs (see Figure 4) at both
ends of this corridor which are operated by the traffic operations
center out of Boston.
Merging from some of the area on-ramps was discussed. A
Figure 4 Current VMS
specific example mentioned was the on-ramp from Grafton
Street (Exit 14) that has a high jersey barrier, which obstructs
visibility of traffic streams, both entering and main line, from
one another (see Figure 5). Another cited on-ramp was from
East Central Street where drivers nervous about weaving
attempt to do so as quickly as possible, often before it is safe.
Other significant factors mentioned at the outset of the meeting
included the following:
Figure 5 On-ramp from
o A clogged catch basin near Vernon Street;
Grafton Street
o Condition of existing pavement markings and signage;
o Overall pavement conditions;
o Condition of cobblestones and/or markings for on-ramps; and
o Condition of crash cushions for off-ramps.
Page 7
4.0 Summary of Short Term Recommendations for I-290 through Worcester
The formal review of potential safety concerns along I-290 was completed by the entire audit team.
Following identification of a potential safety issue, the dialogue focused on possible countermeasures
with some preliminary discussion regarding the feasibility of implementation (timeframe and cost) as
well as the potential payoff of safety benefits. Given the potential for an immediate impact, there was
an added focus on short term (less than 1 year) and low cost (less than $10,000) improvements that
could be implemented quickly resulting in a positive safety impact. Unlike other roadways being
evaluated as part of the Massachusetts LD-RSA process, some of the opportunities for I-290 are
limited because of its Interstate classification. Additionally, it may be expected that associated costs
for recommended strategies may be higher again because of the Interstate classification. For example,
routine maintenance may cost more in this application because of the challenges and requirements for
completing this along the Interstate.
Based partly in response to concern from the Massachusetts State Police, the Massachusetts Highway
Department previously reviewed opportunities that would enhance communication of the changing
roadway environment to drivers on either side of this roadway segment. In particular, there was a
desire to alert drivers of the speed reduction and curvature. A summary of the complete changes,
which includes the proposed changes as well as discussion regarding other alternatives that were
deemed not applicable, is included in the Appendix. Some of the proposed signage scheduled to be
added in the spring of 2008 is shown in Figure 6.
Figure 6 Proposed Signage for Interstate 290
Page 8
A majority of the remaining short-term recommendations were related to general maintenance and
included some of the following tasks:
•
•
•
•
•
•
Replace worn or damaged signage (e.g. Exit 19 WB sign was downed at time of field visit);
Repair glare paddles that are damaged around horizontal curve near I-190;
Reapply pavement markings that are currently very worn through/north of downtown area and
consider exploring higher quality markings based upon benefit/cost analysis;
Repair loose cobblestones in the area near several on-ramps;
Inspect crash cushions at off-ramps including sand barrels that were broken open (EB in
downtown area) at the time of the field visit; and
Inspect and repair catch basin near Vernon Street which floods the nearby by ramp in the
eastbound direction.
Some other short term recommendations that should be considered are listed below.
•
•
•
Enhance signage near Grafton Street on-ramp that would alert drivers of oncoming traffic.
Please note that longer-term strategies should possibly be considered here as the limited sight
distance could be problematic. Examples may include installation of a device that separates
traffic streams until sight distance for the weave is provided.
Identify opportunities to utilize and expand upon the ITS infrastructure that is in place. From a
safety perspective, the most recognizable safety benefit would be communication of dynamic
roadway conditions to drivers (i.e., congestion ahead, crash ahead, etc.).
Consider modifications at adjacent surface streets that would help prevent vehicles from
queuing on to the I-290 mainline. Many different types of modifications have the opportunity
to result in potential improvements to safety along I-290. A specific example is the proposed
signal timing modifications at Lincoln Square.
5.0 Summary of Additional I-290 Countermeasures
Although an emphasis was placed upon short term and low cost improvements that could be carried
out immediately, the focus of the team was not limited to those constraints. The following section
details countermeasures discussed by the team, which are reflective of all costs and timeframes and
includes both general (entire corridor) and specific safety opportunities. Please note that with respect to
the timeframe, there are some unknown variables that must be further explored. Several definitions
exist for low, mid, and high cost as well as for short, mid and long term implementation timeframes.
For purposes of this report, low cost improvements will be under $10,000, mid costs will be under
$50,000, and high costs will be above $50,000. From a timeframe perspective, short term will refer to
implementation timeframes less than 1 year, while mid and long term will refer to countermeasures
that will take 1 to 3, and greater than 3 years, respectively.
Page 9
Potential
Safety Issue
Possible Countermeasures
Continue with proposed signage
recommended by MassHighway (see
Appendix for details).
Communicating
changing conditions
After the signage is added, an
to drivers,
specifically, speed evaluation should be completed to
reduction & curvature determine its effectiveness, which
may result in the identification of
other safety opportunities.
Interchange
improvements
Explore
ways
of
improving
operations at these intersections
where congestion problems have
been reported and consider how this
may tie in with current/proposed
developments.
Implementation
Timeframe
Potential Safety
& Cost
Payoff
Short Term &
Low Cost
High
Short Term &
Low Cost
Low
Photos
Solutions of all
timeframes, costs, and
safety payoffs are
possible
Short Term &
Low Cost
Concrete medians
barriers
Add median barrier reflectors.
Sight distance at
Grafton Street on
ramp to I-290EB
Enhance signage near Grafton Street
on-ramp that would alert drivers of
oncoming traffic.
Short Term &
Low Cost
Low
Driver behavior
issues
Explore expanded partnerships with
HSD for education and enforcement
support regarding high speed,
aggressive driving and road rage,
distracted driving, and tailgating.
Short Term &
Low/Mid Cost
Mid/High
Low
Page 10
Possible Countermeasures
Implementation
Timeframe
& Cost
Repair poor pavement areas (e.g.
through / north of downtown).
Long Term
& High Cost
Mid/High
Perform catch basin inspection to
improve
current
drainage,
specifically the I-290 EB catch basin
near Vernon Street.
Short Term &
Low Cost
Low/Mid
Markings &
delineation
Improve
pavement
markings
through/north of downtown and
evaluate highly reflective and
durable pavement markings using a
benefit /cost analysis.
Mid Term &
Mid/High Cost
High
Expand ITS
related activity
Integrate ITS technology such as
cameras and variable message signs,
which can be employed for
monitoring (operations or crashes),
driver
feedback
regarding
congestion, or weather conditions.
Long Term &
High Cost
Mid/High
Potential
Safety Issue
Drainage and
pavement concerns
Consider alternative to eliminate Short Term &
Low Cost;
confusing center lane merge, and
Merge from
provide a more orderly flow through however actual
I-190 with I-290WB
5-lane
cross-section
where improvement will
unnecessary weaves are made.
be long-term
Potential
Safety Payoff
Photos
Low
Page 11
6.0 Discussion
As previously noted, the opportunities for safety improvements for I-290 may be somewhat restrictive
or expensive as compared to other roadways. Nevertheless, it is important to note that for the safety
improvement opportunities described in the previous sections: 1) many treatments are both low cost and
short term; and 2) there is a complimentary nature of many of the safety strategies in that one
improvement may address multiple safety issues. Please note that although this document provides a
series of specific recommendations which warrant short term implementation, it should be noted that
the approach towards improved safety is dynamic in nature and warrants revisiting over time. It is also
worth noting that some of the modifications may already be in the process of implementation. For
example, proposed signage is scheduled for spring 2008; some of this may be included as part of
current construction, and the remainder should be considered moving forward.
Several additional topics that were discussed at the audit meeting and warrant consideration.
•
•
•
•
Some discussion was focused upon the closure and/or consolidation of on-ramps, such as the
two on-ramps from Grafton Street. As another example, it was noted that the Vernon Street
ramp was closed during construction, and it was also noted that Belmont Street to I-290WB is a
high rear-end crash location. In the end, it was believed that existing volumes were too high for
such closures; however perhaps these could be explored with any long-range plans in the future.
Another element discussed related to interchanges was the I-290 EB split at I-190, and in
particular the weave from the Lincoln Street on ramp. There was a suggestion to add a lane
from the ramp and continue it through. This may be considered, moving forward.
Success stories were woven in to the discussion as well. Two safety aspects that were cited
included the curve delineation as well as the improved roadway lighting.
There was some discussion at the RSA meeting regarding what lessons could be learned from
the major construction effort undertaken on I-290. It may be worth developing a brief report
which reflects upon the work zone practices and their impacts; this which may be useful in
developing future work zones across the Commonwealth.
Page 12
7.0 Appendix: Distributed RSA Meeting Materials
Materials provided to RSA team members in advance of the meeting included the following:
1.
2.
3.
4.
5.
6.
Agenda
RSA and Lane Departure Introduction
Crash Data Summary
Geo-Located Crash Map
LD-RSA Checklist
MassHighway Letter Detailing Proposed Signage
Page 13
Road Safety Audit for Worcester I-290
Meeting Place: Central Mass Regional Planning Commission
35 Harvard Street, Worcester
Wednesday, November 28, 2007
9:00 – 11:00 AM
Type of meeting:
Lane Departure – Road Safety Audit
Attendees:
Invited Participants to Comprise a Multidisciplinary Team
Please bring:
Thoughts and Enthusiasm!!
9:00 AM
Welcome and Introductions
9:15 AM
Introduction to Road Safety Audits and Lane Departure Crashes
9:30 AM
Review of Site Specific Material
• Crash & Volume – provided in advance
• Existing Geometries and Conditions
• Video and Images
10:00 AM
Completion of RSA
• Identification of Safety Concerns – using checklists as a guide
• Identification of Possible Countermeasures
11:00 AM
Adjourn for the Day – but the RSA has not ended
Instructions for Participants:
• Before attending the RSA on November 28th participants are encouraged to drive
I-290 within Worcester, MA and complete/consider elements on the RSA advisory
checklist with a focus on safety factors affecting roadway departure crashes.
• 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 initial 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.
Page 14
Introduction to Road Safety Audits & Lane Departure Crashes in Massachusetts
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:
•
•
Minimize the risk and severity of road crashes that may be affected by the existing or future
roadway at a specific location or nearby network;
Improve the awareness of safe design practices which are likely to result in safety benefits based
upon potential safety concerns.
Although RSA’s have been employed in other countries for some time, they are being fully embraced
across the United States as a low cost opportunity to make significant safety improvements at any
number of stages ranging from project development and planning through existing operation.
Furthermore, RSA’s have proven to be effective on projects of all shapes and sizes. The RSA program
here in the Commonwealth prevents a unique and exciting opportunity for improvements in roadway
safety.
The RSA program in Massachusetts is being 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). Lane departure crashes are a notable problem area for
Massachusetts, especially for crashes with higher injury severities. Between 2002 and 2004, lane
departure crashes accounted for nearly 20 percent of all crashes in Massachusetts and approximately
one-quarter of crashes involving an incapacitating injury. Almost one-half of fatal crashes between
2002 and 2004 were lane departure crashes. As the crash severity increases, so does the percent of
crashes that are lane departures as shown in the figure below.
All Massachusetts Crashes,
2002-2004
Massachusetts Incapacitating
Injury Crashes, 2002-2004
18.7%
Lane Departure Crashes
Massachusetts Fatal Crashes, 20022004
24.5%
46.2%
Other Crashes
In an effort to combat the lane departure problem, a strategy was developed for the SHSP to identify hot
spot lane departure location, perform road safety audits and implement low-cost comprehensive
countermeasures.
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GEOMETRIC DESIGN –
Issue
Comment
A. Speed – (Design Speed; Speed Limit & Zoning; Sight Distance; Overtaking
Are there speed-related issues along the corridor?
Please consider the following elements:
• Horizontal and vertical alignment;
• Posted and advisory speeds
• Driver compliance with speed limits
• Approximate sight distance
• Safety passing opportunities
B. Road alignment and cross section
With respect to the roadway alignment and crosssection please consider the appropriateness of the
following elements:
• Functional class (Urban Principal Arterial)
• Delineation of alignment;
• Widths (lanes, shoulders, medians);
• Sight distance for access points;
• Cross-slopes
• Curbs and gutters
Drainage features
C. Intersections
For intersections along the corridor please consider all
potential safety issues. Some specific considerations
should include the following:
• Intersections fit alignment (i.e. curvature)
• Traffic control devices’’ alert motorists as
necessary
• Sight distance and sight lines seem appropriate
• Vehicles can safely slow/stop for turns
• Conflict point management
• Adequate spacing for various vehicle types
Capacity problems that result in safety problems
D. Auxiliary lanes
• Do auxiliary lanes appear to be adequate?
• Could the taper locations and alignments be
causing safety deficiencies?
• Are should widths at merges causing safety
deficiencies?
Page 21
E. Clear zones and crash barriers
For the roadside the major considerations are clear
zone issues and crash barriers. Consider the following:
• Do there appear to be clear zones issues?
⎯ Are hazards located too close the road?
⎯ Are side slopes acceptable?
• Are suitable crash barriers (i.e., guard rails,
curbs, etc.) appropriate for minimizing crash
severity?
• Barrier features: end treatments, visibility, etc.
F. Bridges and culverts – (if necessary)
Are there specific issues related to bridges and culverts
that may result in safety concerns?
G. Pavement – (Defects, Skid Resistance, and Flooding)
• Is the pavement free of defects including
excessive roughness or rutting, potholes, loose
material, edge drop-offs, etc.) that could result
in safety problems (for example, loss of
steering control)?
• Does the pavement appear to have adequate
skid resistance, particularly on curves, step
grades and approaches to intersections?
• Is the pavement free of areas where flooding or
sheet flow of water could contribute to safety
problems?
• In general, is the pavement quality sufficient
for safe travel of heavy and oversized vehicles?
H. Lighting (Lighting and Glare)
It is important to consider to the impacts of lighting.
Some specifics include the following:
Is lighting required and, if so, has it been
adequately provided?
Are there glare issues resulting from headlights
during night time operations or from sunlight?
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TRAFFIC CONTROL DEVICES
Issue
Comment
I. Signs
Signage is a critical element in providing a safe
roadway environment. Please consider the following:
• Are all current signs visible? Are they
conspicuous and clear? Are the correct signs
used for each situation?
• Are signs visible (consider both night and day)?
• Does the retroreflectivity or illumination appear
satisfactory?
• Are there any concerns regarding sign
supports?
J. Traffic signals
Although the focus of this RSA are lane departures,
this does present an opportunity for us to consider any
traffic signals. Specifically:
• If present, do the traffic signals appear to be
designed, installed, and operating correctly?
• Is the controller located in a safe position?
(where it is unlikely to be hit, but maintenance
access is safe)
• Is there adequate sight distance to the ends of
possible vehicle queues?
K. Marking and delineation
• Is the line marking and delineation:
⎯ appropriate for the function of the road?
⎯ consistent along the route?
⎯ likely to be effective under all expected
conditions? (day, night, wet, dry, fog, rising
and setting sun, oncoming headlights, etc.)
• Are centerlines, edgelines, and lane lines
provided? If not, do drivers have adequate
guidance?
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ROADWAY ACTIVITY
Issue
With respect to roadway activity please consider safety
elements related to the following:
• Pedestrians
• Bicycles
• Public transportation vehicles and riders
• Emergency vehicles
• Commercial vehicles
• Slow moving vehicles
Comment
ENVIRONMENTAL CONSIDERATIONS
Issue
Comment
Weather & Animals
From an environmental perspective it is important to
consider any potential impacts. Most notably is likely
to be the impacts of weather or animals, including:
• Possible effects of rain, fog, snow, ice, wind on
design features.
• Has snow fall accumulation been considered in
the design (storage, sight distance around
snowbanks, etc.)?
• Are there any known animal travel/migration
routes in surrounding areas which could affect
design?
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