Prepared by
Franklin Regional Council of Governments and
University of Massachusetts Traffic Safety Research Program
Massachusetts Highway Department
Prepared for
May 2008
Federal Highway Administration

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 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 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 to does the percent of crashes that are lane departures as shown in Figure 1.
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 enclosed following report summarizes the findings of a RSA focused on lane departure crashes (LD) along Route 2 in Shelburne, Massachusetts.
Page 2

Shelburne, home to approximately 2,050 residents, is a Massachusetts municipality located in Franklin
County in the Northwestern part of the state. Route 2 through Shelburne is the gateway to the popular tourist attraction of the Village of Shelburne Falls, which boasts the natural attractions such as the glacial potholes and Salmon Falls and the famous Bridge of
Flowers, which draw large volumes of seasonal traffic along the corridor. This traffic can become particularly heavy during the fall season when foliage drives are popular. It is worth noting that Route 2 is a designated State and National Scenic
Byway, known as the Mohawk Trail Scenic Byway.
In addition to the high seasonal variation, the traffic volumes along Route 2 are fairly mixed with passenger cars, motorcycles, commercial motor vehicles, as well as bicycles.
Route 2 is a two-lane, bidirectional rural principal arterial
Figure 2 Route 2 in Shelburne roadway spanning approximately 7.5 miles through
Shelburne, and more globally, Route 2 is part of the National Highway System connecting Boston, MA to Buffalo, NY. The stretch of Route 2 under observation (located only in Shelburne) has lane widths of 12 ft. with 6-inch longitudinal pavement markings and 8-10 feet paved shoulders. The full length of
Route 2 through Shelburne was resurfaced in July 2007. Frequent horizontal and vertical curves make up this stretch of roadway.
A sample cross-section is pictured in Figure 2. Although the entire corridor through Shelburne was considered, a specific focus of this RSA was a 0.6 mile stretch approximately 1.25 miles west of the Greenfield town line, where 12 lane departure crashes occurred between 2003 and 2006.
The LD-RSA for Route 2 was held on July 11, 2007 at the Franklin Regional Council of Governments
Planning Department Conference Room .
In total, 12 team members participated in the road safety audit as listed in Table 1. As indicated in Table 1 representatives were present from Federal, State,
Regional and Local agencies and included a cross-section of engineering/planning, education, and enforcement expertise.
Table 1 Participating Audit Team Members
Audit Team Members
Bonnie Polin
Jennifer Inzana
Neil Boudreau
Alex Normandin
Richard Marquis
Laurie Scarbrough
Patrick Tierney
Tim White
Keith Wilson
One Hwang
Dennis Eugin
Michael Knodler
Agency/Affiliation
Massachusetts Highway Department – Safety Section
Massachusetts Highway Department – Safety Section
Massachusetts Highway Department – Traffic Engineering
Massachusetts Highway Department
Federal Highway Administration
Massachusetts Highway Department, District 2
Massachusetts Highway Department, District 1
Federal Highway Administration
Franklin Regional Council of Governments
Massachusetts Highway Department – Chief’s Office
Massachusetts State Police
University of Massachusetts - Amherst
Page 3

Given the length of the Route 2 through Shelburne and the relative unfamiliarity of many audit team members with the roadway, participants were asked to visit the site in advance of 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 meeting invitees prior to the meeting (this information is included in the Appendix this report). Specifically, the additional information provided was pertinent to the LD-RSA safety initiative and included traffic volumes and speeds as well as a description of relevant crashes as summarized below:
•
Table 2 presents daily directional volumes collected as part of a 9-day volume study completed in August of 2004 by the Franklin Regional Council of Governments (FRCOG). As shown in
Table 2 the directional splits are approximately equally with an average weekday ADT of
14,112 vehicles and weekend ADT of 13,367 vehicles. The data were collected nearly one half mile east of the Shelburne Town line in Greenfield. A March 2006 volume study completed just west of the Shelburne/Greenfield town line by MassHighway reported an average weekday
ADT of 11,274 vehicles.
•
The posted speed along Route 2 in Shelburne is primarily 50 mph with a small stretch of roadway posted at 45 mph. The official speed regulations for Route 2 in Shelburne are summarized in Table 3.
•
Between 2003 and 2006 there were 40 reported crashes consistent with the lane departure initiative which were geolocated and presented in Figure 3. A more detailed summary of the 12 lane departure crashes in the specific 0.6 mile section under consideration are presented in
Figure 4. A complete summary of the 40 identified crashes over the 4-year period was provided to participants prior to the audit meeting. Please note that this does not reflect all crashes along
Route 2, but those deemed relevant to this lane departure initiative.
Table 2 Traffic Volumes for Route 2 – Collected August 2004
Eastbound Volumes
Daily AM PM
Date Volume
Wed. 8/11/04 7,005
Peak
586
Peak
511
Thur. 8/12/04 7,214
Fri. 8/13/04 7,530
Sat. 8/14/04 7,438
596
576
710
493
556
582
Sun. 8/15/04 6,226
Mon. 8/16/04 6,620
Tue. 8/17/04 6,975
Wed. 8/18/04 6,903
528
572
562
566
591
471
512
496
Westbound Volumes
Daily AM PM
Volume
6,922
7,105
8,168
7,902
5,168
6,304
6,857
6,893
Peak
384
354
474
633
362
359
430
418
Peak
671
725
773
713
487
680
683
669
Total Daily
Volumes
13,927
14,319
15,698
15,340
11,394
12,924
13,832
13,796
Thur. 8/19/04 7,086 564 490 7,207 412
Table 3 Summary of Speed Regulations for Route 2 in Shelburne
670 14,293
Westbound Eastbound
Beginning at the Greenfield line
7.14 miles at 50 mph
0.39 miles at 45 mph
Ending at the Buckland line
Beginning at the Buckland line
0.39 miles
7.14 miles
At 45 mph
At 50 mph
Ending at the Greenfield line
Page 4

Primary focus area of LD-RSA.
0.6 mile stretch of Route 2 with
12 crashes between 2003 and
2006 (see Figure 4)
Figure 3 4-Year Summary of Route 2 Lane Departure-Related Crashes.
Page 5

Figure 4 Summary of Details for Selected Crashes on Route 2 in Shelburne.
Page 6

Following a brief introduction to the RSA process in general, the meeting participants were asked to summarize and characterize potential safety considerations along Route 2. The initial characterization of the major safety considerations focused on several key elements as follows:
•
Weather was discussed as a possible factor in a significant percentage of the considered crashes. The most common weather events involved vehicles sliding/losing control due to roadway conditions, and given the proximity of the adjacent travel lane or roadside resulted in a lane departure crash.
•
Another point of consideration at this stage of the RSA was access from adjoining roadways and driveways. Specifically noted were challenges with queued vehicles (e.g. not recognizing stopped vehicle) and the speed differential amongst vehicles.
•
Driver expectancy on this segment was listed as a possible concern and can be improved along this corridor. A fair portion of crashes occurred during adverse weather conditions or on a horizontal curve and advanced warning signs can be used to address both of these crash contributing factors. Also related to increasing driver expectancy was concern regarding animal crossings in the area.
•
Route 2 does not have any lighting. Poor lighting paired with signage that is difficult to interpret due to age or other reasons can create an unsafe environment for motorists. Solar panel lighting or other such lighting along this corridor can improve visibility, especially at night.
•
Other significant factors mentioned at the outset of the meeting that are discussed in further detail later in this report also included the following:
⎯
Passing opportunities (see Figure 5);
⎯
The presence of slower moving vehicles and absence of climbing lanes;
⎯
Driver expectancy at intersections;
⎯
Concern about increased traffic volume from future developments. For example, a condominium development project at Mount
Snow ski resort in Vermont may increase traffic volumes at and to the east of the Colrain-
Figure 5 Route 2 Passing Zones
Shelburne Road intersection as this is a route used by many to access this resort ; and
⎯
The presence of motorcycles and bicycles which frequent this stretch of roadway.
The formal review of potential safety concerns along Route 2 was completed by the entire audit team.
Following identification of a potential safety issue the dialogue subsequently 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
Page 7

$10,000) that could be done almost instantaneously resulting in a positive safety impact. Resulting recommendations for immediate actions along Route 2 include the following:
•
The placement of uniform chevron alignment signs at selected horizontal curves. Nearly all horizontal curves along Route 2 have advanced curve warning signs which show side street configurations (see Figure 6); however curve chevron signs and possibly roadside reflectors could be used at sharper horizontal curves. Specific locations would include the curve at Shelburne Summit Drive as well as Old Greenfield Road.
•
It is also recommended that advanced warning signs be installed in relevant areas such as: “Slippery When Wet”,
“Cross Road”, advance street name, or animal crossing signs
(near power line crossing). Please note that there is already
Moose Crossing signage (see Figure 7) in place along the
Figure 6 Advance Curve corridor.
•
Replace signage that is faded or worn with highly retroreflective signage. Please note that a majority of signage along this corridor is properly placed and in good condition, and this recommendation is intended to highlight the importance of this practice moving forward.
•
It is recommended that street signs with a 4 inch legend be replaced with more legible street signs (6 inch legend) and be
Figure 7 Moose Crossing made more visible.
•
Another recommendation for enhanced centerline visibility and delineation may be the addition of raised reflective pavement markers.
•
Continue maintenance of roadway: pavement surface, pavement markings, and edges to prevent edge line drop off.
•
It is recommended that existing passing zones be analyzed to verify they are of appropriate length and provide adequate sight distance. The general sense at the RSA is that they are currently adequate, but should be revisited. A longer-term possibility for consideration would include the addition of passing and/or climbing lanes.
•
Some general trimming and landscaping can help improve sight distance around horizontal curves, and driveways.
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 solely those countermeasures. 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 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 8

Potential
Safety Issue Possible Countermeasures
Implementation
Timeframe
& Cost
Potential Safety
Payoff
Reflectorize existing guard rails along the entire corridor
Short Term &
Low Cost
Mid
Photos
Addition of curve ahead and chevron alignment warning signs and roadside reflectors at Old Greenfield
Road and Shelburne Summit Drive curves
Short Term &
Low/Mid Cost
Mid
Horizontal curvature
Maintain landscape and roadside to improve sight distance around curves
Short Term &
Low Cost
Low
Revisit crash data and consider additional guardrail along roadway at horizontal curves where there are crashes with fixed objects or embankments
Mid Term &
Mid Cost
Mid
Where loss of grip on horizontal curves has been found to be a contributing factor in crashes consider applying a high friction surface treatment such as TyreGrip.
Short/Mid Term
& Low/Mid Cost
Mid/High
Page 9

Potential
Safety Issue
Distracted or drowsy drivers
Possible Countermeasures
Implementation
Timeframe
& Cost
Consider rumble strips/stripes in non residential areas along roadway
Mid Term &
Mid Cost
Potential
Safety Payoff
Mid
Install raised centerline pavement markers to improve roadway delineation
Short Term &
Low/Mid Cost
Centerline and/or edge line crossover Consider installation of a median barrier between opposing traffic streams at locations with high frequency cross over the centerline crashes occur
Mid/Long Term
& High Cost
Late notification of approaching intersection
Install advanced warning signs indicating that there is an intersection ahead, and the cross street name(s). Ensure all street signs have 6 inch legend. A specific example is Colrain-Shelburne Road
Short Term &
Low/Mid Cost
Accommodating large program “Motorcycles are
Everywhere” administered by the tourist and motorcycle
Highway Safety Division populations
Participate in an educational
Provide notification of popular tourist attractions / intersections
Short Term &
Low Cost
Short Term
& Low Cost
Mid
High
Mid
Low
Mid
Photos
Page 10

Potential
Safety Issue Possible Countermeasures
Speed variance from cars entering/exiting the roadway and slow moving vehicles
Provide climbing lanes for slower vehicles and trucks if the percentage of trucks exceeds thresholds.
Add turn lanes at selected side street and driveways as volumes warrant
Implementation
Timeframe
& Cost
Long Term &
High Cost
Long Term &
High Cost
Potential
Safety Payoff
Mid/High
High
Minimizing the effects of lane departure; crossing the edge line
Maintain and fill roadside as needed to prevent edge drop-off
Provide road edge with guardrail
Install guardrail end treatments on all sections of guardrail
Short Term &
Low Cost
Mid Term &
Mid/High Cost
Short Term &
Mid Cost
Low
High
Mid/High
Dark stretches of
Roadway
Consider installation lighting along dark stretches of road. Solar power lighting may be a good option for this location
Long Term &
Mid/High Cost
Mid
Continued maintenance
The pavement condition, drainage, and coverage resulting from brush are in good condition. To assure safety this needs be maintained
Weather-related crashes along the
Route 2 corridor
Add warning signs alerting motorists of possible weather impacts.
Employ a VMS periodically during the winter months to remind motorists about weather issues.
Short Term &
Low Cost
Short Term &
Low Cost
Mid
Mid
WINTER
WEATHER
Photos
Page 11

With respect to the safety improvement opportunities described in the previous section it is important to consider the following: 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 will aid with 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.
The designation of Route 2 as a State and National Scenic Byway (Mohawk Trail Scenic Byway) is an important consideration, as any of the changes implemented must be sensitive to this designation. The full Mohawk Trail Corridor Management Plan can be viewed online at http://frcog.org/pubs/index.php#trans
An additional topic discussed at the meeting was the potential impacts from future development which could add more traffic to the Route 2 corridor. As noted, Route 2 has a mixture of residential and commercial zoning along its length and the RSA team felt strongly that any future development should attempt to minimize where possible the number of curb cuts that access Route 2. Additionally, the safety impact of any new curb cut or roadway needs to be accounted for in the MassHighway permitting process.
Page 12

Materials provided to RSA team members in advance of the meeting included the following:
1.
Meeting Invite
2.
RSA and Lane Departure Introduction
3.
Summary of Traffic Volumes
4.
LD-RSA Checklist
Please note that team members were also provided with the crash summaries prepared by FRCOG that were presented in Figure 3 and 4.
Page 13

Page 14

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 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 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.
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.
Page 15

Page 16

Page 17

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 18

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?
Page 19

TRAFFIC CONTROL DEVICES
Issue
I. Signs
Signage is a critical element in providing a safe roadway environment. Please consider the following:
•
Are all current signs visible (consider both night and day)? Are they conspicuous and clear? Are the correct signs used for each situation?
•
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?
Comment
Page 20

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
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?
Comment
Page 21