ROAD SAFETY AUDIT Route 57 Agawam MAJOR HIGHWAY MEDIAN CROSS-OVER CRASHES

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ROAD SAFETY AUDIT
MAJOR HIGHWAY MEDIAN
CROSS-OVER CRASHES
Route 57 Agawam
Prepared for
Prepared by
MS Transportation Systems, Inc.
Framingham, Massachusetts
March 2009
ROAD SAFETY AUDIT
MAJOR HIGHWAY MEDIAN
CROSS-OVER CRASHES
ROUTE 57 AGAWAM
Final Report
March 2009
Prepared for
Massachusetts Highway Department
Prepared by
MS Transportation Systems, Inc.
300 Howard Street P.O. Box 967
Framingham, Massachusetts 01701
Tel: 508-620-2832 Fax: 508-620-6897
www.mstransportationsystemsinc.com
TABLE OF CONTENTS
Page
INTRODUCTION
1
RSA PROCESS
3
ANALYSIS
7
SUMMARY OF RSA FINDINGS/POTENTIAL ACTIONS
11
RECOMMENDATIONS
18
APPENDIX
22
Route 57 Agawam Road Safety Audit
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Route 57 Agawam Road Safety Audit
Introduction
Lane departure crashes are one of the primary fatal crash types in Massachusetts. The
Commonwealth exceeds the national average for the proportion of fatal lane departure
crashes and was designated a lead state in lane departure crashes by the American
Association of State Highway and Transportation Officials (AASHTO).
The
Massachusetts Highway Department (MassHighway) conducted a study of the problem
and found that during 2002-2004, lane departure crashes accounted for 25 percent of all
injury crashes and nearly half, 46 percent, of all fatal crashes.
As part of the effort in implementing the safety plan and specifically reducing lane
departure crashes, the MassHighway is completing a Road Safety Audit (RSA) Review
Project specifically focused on median crossing (or median cross-over) crashes on its
major highways. Road safety audits are a formal safety performance examination on
existing or future roadways by an independent audit team. These specific audits are
being conducted in locations where cross-over experience has been or has the potential
to be of concern and where the RSA team has judged that factors exist and safety risk
could be affected. The team works to identify opportunities for enhancing safety and to
recommend specific enhancements that may be implemented to reduce median crossover crashes and improve the overall safety along the highway.
A RSA was conducted for Route 57 in Agawam as part of this project. Figure 1 indicates
the corridor section under study, a distance of approximately 4.6 miles. The “open”
median section area totals approximately 3.9 miles within the overall study section. This
section had experienced a number of median related crashes, including several crossmedian crashes.
The purpose of this Route 57 Agawam RSA is to identify current safety conditions on the
Route 57 divided section and to recommend a set of actions to address the identified
issues. Recommendations contained in this report reflect the overall consent of the RSA
team and do not necessarily reflect the official views of MassHighway.
MS Transportation Systems, Inc.
Page 1
5
147
Feeding Hills
PROJECT
TERMINUS
75
57
Springfield
Street
Mill
Street
159
PROJECT
TERMINUS
South
Westfield Street
Agawam
- interchanges
N
Project Location
W
S
Route 57 Road Safety Audit
Agawam, Massachusetts
MS Transportation Systems, Inc.
E
1 : 25,000
Framingham, Massachusetts
FIGURE 1
Route 57 Agawam Road Safety Audit
RSA Process
The general process outlined in the guideline1 was essentially followed although with
some minor variations incorporated in the overall procedure. These were due in part to
the project location being a high speed, high volume section of an access controlled
highway. With these characteristics, there are limited areas to safely stop and gather as
a group along the section without potentially hindering traffic flow or the safety of the
RSA team. Given the team size and general character with the corridor, the team
members who visited the site prior to the team meeting did so either individually or in
smaller groups. A video recording of a drive-thru in both directions was collected by the
RSA consultant and used at the meeting to review conditions as a group. Background
material and plans were transmitted to the RSA consultant to compile and review prior to
the initial RSA team meeting. Crash and traffic volume data were transmitted to RSA
team members prior to the meeting as well. Once the initial RSA team meeting was
conducted, the RSA consultant gathered the input completed the analysis and prepared
a draft document for team members to review. Data including summary crash records
for the 2004-2007 period, six (6) detailed crash descriptions of cross-over crashes, and
available record highway plans were obtained and reviewed by the RSA consultant.
•
RSA Team
The following individuals participated in of the Route 57 Agawam Road Safety Audit:
Lt. Steven Hughes, State Police Springfield
Sam Gregorio, MassHighway, District 2
Bao Lang, MassHighway, District 2
Khyati Parmar, PVPC
Hal Piligian, MassHighway, District 2
Trung Vo, MassHighway, District 2
Robert Fay, MassHighway
Lyris Liautaud, MassHighway
•
Lisa Schletzbaum, MHD Safety
Xian Chen, MassHighway
Gary Roux, PVPC
John Donoghue, MassHighway, District 2
Ken Wanar, MassHighway
William Goulet, MassHighway, District 2
Kathryn Cook, MassHighway
William J. Scully, MS Transportation Systems
(RSA Consultant)
RSA Meeting
A meeting was held on June 18, 2008 at the MassHighway District 2 Office. At the
meeting, the RSA consultant provided a brief overview of the RSA purpose, a summary
of the roadway section’s characteristics and results of the review to date. The RSA
team listed above was present at the meeting. The video record of Route 57 taken while
driving the corridor was viewed. During and following the video, discussions related to
the potential factors affecting the safety along the corridor and possible solutions to
1
MS Transportation Systems, Inc., Road Safety Audits, Median Cross-Over Crashes, Audit Guidelines,
Prepared for MassHighway, October 2007.
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Route 57 Agawam Road Safety Audit
enhance the overall safety took place. The RSA team members provided input on the
key items observed in the field and those items that were listed on the RSA Median
Cross-Over Prompt List.
Key items noted at the meeting included:
 It was noted to be a “fast” road – speed data showed the 85th percentile
speeds in the mid-60’s.
 There are regular enforcement patrols but efforts are limited by funds, staff
and other priorities in the region.
 In general, motorists on Route 57 are familiar with the roadway although with
a large amusement park (Six Flags) located off Route 159, there are also a
number of roadway users who are occasional or infrequent motorists on
Route 57 and would be relying on adequate guidance and warning signs.
 Overall, the team members felt the drive was generally comfortable (with
existing geometry) with the exception of the westbound lane drop at the Main
Street interchange.
 Excessive speeds were cited as a major contributing factor in the crash
experience.
 The route can largely be characterized as “dark” (i.e. no overhead lighting). A
combination of faded markings and no edge guidance with high speeds may
be contributing to some of the late night crashes.
Following the RSA meeting, the RSA consultant compiled the information, for inclusion
on the analysis and in the development of recommendations.
•
Analysis Procedures
As previously indicated, the RSA analysis generally followed the procedures described
in the Guideline with some variations and also took into consideration the methods
published by the Federal Highway Administration2 and those included in training
materials3. The basic tasks included:
2
3
Federal Highway Administration, FHWA Road Safety Audit Guidelines, Publication No. FHWA SA-06-06,
Washington, D.C., 2006.
Federal Highway Administration, Resource Center, Road Safety Audits Mini-Workshop, Jeffrey Shaw, PE,
PTOE, presented to New England ITE Section, September 19, 2006.
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Route 57 Agawam Road Safety Audit
•
•
•
•
Obtaining and reviewing crash and other traffic characteristic data and
available record plans.
Conducting site reconnaissance and collecting a current record of condition
via photos and video,
identify potential hazardous issues, and
Identify and evaluate potential actions to address the noted issues.
In assessing the issues identified by the RSA Team, the relative seriousness and
potential risk relative to crash frequency and severity were determined. Using the
FHWA guidelines as input and considering characteristics of this specific RSA, the
relative frequency criteria and severity criteria were identified and are presented in Table
1 and Table 2, respectively.
TABLE 1
FREQUENCY RATING
ESTIMATED
Exposure
high
medium
high
medium
low
high
Probability
high
high
medium
medium
high
low
low
medium
low
medium
low
low
EXPECTED CRASH FREQUENCY
(PER AUDIT ITEM)
5 or more crashes per year
FREQUENCY
RATING
Frequent
1 to 4 crashes per year
Occasional
Less that 1 crash per year, but
more than 1 crash every 5 years
Infrequent
Less than 1 crash every 5 years
Rare
Source: FHWA RSA Training Workshop
TABLE 2
SEVERITY RATING
Typical Crashes Expected
(per audit item)
High-speed crashes; head on and
rollover crashes
Moderate-speed crashes; fixed
object or off-road crashes
Crashes involving medium to low
speeds; lane changing or
sideswipe crashes
Crashes involving low to medium
speeds; typical of rear-end or
sideswipe crashes
Expected Crash Severity
Probable fatality or
incapacitating injury
Moderate to severe injury
Severity
Rating
Extreme
High
Minor to moderate injury
Moderate
Property damage only or
minor injury
Low
Source: FHWA RSA Training Workshop
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Taking into consideration both frequency and severity, the relative risk of a particular
audit item was rated. The risk ratings are shown in Table 3. For each safety issue
identified, the potential seriousness of the issue as well as possible mitigation measures
have been indicated.
TABLE 3
CRASH RISK ASSESSMENT
Frequency
Rating
Low
Frequent
Occasional
Infrequent
Rare
C
B
A
A
Severity Rating
Moderate
High
D
C
B
A
Source: FHWA RSA Training Workshop
Crash Risk Ratings:
A: minimal risk level
B: low risk level
C: moderate risk level
•
Extreme
E
D
C
B
F
E
D
C
D: significant risk level
E: high risk level
F: extreme risk level
RSA Field Audit
Audits were conducted by the team members prior to the RSA meeting. Key notes from
the field work are as follows:
•
In general, comments by team members indicated that the drive along Route 57
in both directions was comfortable.
•
The lane drop along Route 57 westbound at Main Street (Route 159) may come
up as a bit of a surprise to drivers. It was noted that the warning sign is off the
road – on the inside of a curve and partially blocked by vegetation.
•
Certain interchange ramps are well marked (primarily exit ramps) while several
on-ramps (i.e. Garden Street eastbound) are somewhat “hidden” from oncoming
traffic.
•
The overall markings in the west section, in general, are faded and in need of a
new application.
•
The inside shoulder in the eastern section of the highway (east of Route 159)
appears less than two feet in width with a rumble strip.
•
The median is relatively narrow and considered crossable.
•
Speeds are posted at 55 mph.
•
There are imbedded reflectors in the lane lines.
•
Delineator posts along the median are sporadic along the route.
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Route 57 Agawam Road Safety Audit
Analysis
The section of Route 57 under study is a limited access highway that connects with the
Route 5 and I-91 corridors in the east. The section under study is approximately 4.6
miles in length. Within the section there are three full interchanges. The limited access
portion of the highway has an east-west alignment and is fairly gentle in terms of
horizontal and vertical changes. This characteristic ends at Route 187 or South
Westfield Street where Route 57 becomes a two lane undivided roadway. The east
section (east of Route 159 or Main Street) consists of three (3) travel lanes per direction
with a full outside shoulder. West of the Route 159 interchange, the roadway has two
lanes per direction. The outside shoulders are approximately 10 feet wide. Inside
shoulders are in the range of 2 feet in width. Rumble strips exist in both shoulders.
The median is open with the exception of in the vicinity of the interchange underpasses
or overpasses. The width of the median is approximately 46 to 52 feet depending on
location in the study section. The highway east of Route 75 tends to be more in the
higher end of the range while the west section of the highway tends to have a slightly
narrower width (lower part of range). There are several areas where the roadway
curvature and/or topography between the east and west directions lends itself to a crossmedian event once a motorist makes an error and enters the median.
Figure 2 – 6-lane section east of Main Street
Figure 3 – Westbound lane drop at Main Street
Figure 4 – Existing rumble strip and edge
marking
Figure 5 – Median with utility markers
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As was cited in the RSA field audits as well as the RSA team meeting, speeds are
higher than desirable. The posted speed is 55 miles per hour. Pavement markings
were substantially faded in the west section and some of the guide signs, particularly
related to the westbound lane drop may be “hidden” or difficult for the motorist to clearly
notice. These conditions affect lane changing and again, once an error is made, the
median is highly crossable.
Figure 6 – Highly visible markings on exit ramp
Figure 7 – Relatively narrow median with
some elevation difference between direction
A review of available safety data was completed as part of this RSA. The review of data
included crash data of median–related crashes submitted electronically with a crash
narrative and reported for the years 2004 to 2007. The summary table and spot map are
included in the appendix. Key aspects noted in the data included the following:
 A total of 11 median related crashes were noted during this period.
 Of the total, 6 or 55% were cross median crashes.
 There were no median-related fatal crashes reported, however, approximately
67% of the median-related reported crashes resulted in personal injuries.
 A concentration of cross-median crashes occurred in the vicinity of the
interchange with Route 75.
 Nearly two-thirds of the reported crashes occurred in the westbound direction.
 Thirty-six percent (36%) of crashes occurred during the non-light period (i.e.
9PM-5AM)
No one significant or predominant crash reason was given though 3 crashes had speed
cited as a contributing cause and 3 others cited inattention, fatigue and illness as
causes. Reviewing the detailed cross-median crash reports for the section under study,
confirmed these contributing causes and showed driver error or improper driving also
are related causes. In general, the roadway design or physical condition were not
specifically cited as contributing factors although the field audit noted the median is
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Route 57 Agawam Road Safety Audit
considered easily crossable and a number of items relating to driver guidance and
information contribute to once a “mistake” is made, it is difficult to recover in a safe
manner. In addition, the concentration of crashes near the Route 75 interchange may
be affected by the visibility issues in the eastbound direction approaching the Garden
Street on-ramp and/or the characteristics of the acceleration-deceleration lanes in terms
of markings and signage.
Figure 8 – Traveling eastbound prior to Main Street Interchange
The traffic volume observed on Route 57 in this section west of Main Street was
approximately 24,100. While data was not readily available, it is expected that volumes
are higher east of the Main Street interchange. Figure 9 depicts the hourly volume by
direction in August 2007 west of Route 75. In this location, peak period flows in the peak
direction are between 1,100 and 1,200 vehicles per hour with a two-way flow of
approximately 2,000 vehicles per hour.
In summary, the Route 57 Agawam RSA has identified a number of physical and
operational characteristics as being potentially contributing factors to increasing the risk
of experiencing undesirable safety related events although each with varied levels of
seriousness. The major ones include:
¾ Higher travel speeds than desired.
¾ Median is relatively narrow and considered highly crossable.
¾ The lane drop at Route 159 and identification/guidance through the
interchanges potentially cause “quick” lane-changing by motorists.
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Route 57 Agawam Road Safety Audit
Figure 9
Route 57 Directional Volume
The next section will discuss these key issues and the potential actions to consider for
addressing them.
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Route 57 Agawam Road Safety Audit
Summary of RSA Findings/Potential Actions
Based on the field review, the review of crash data and discussions among the RSA
team members, the issues related to the safe operating conditions of the Route 57 in
Agawam study section were identified. There were a number of factors or issues of
concern that were identified as potentially having an effect on the risk and these are
listed in Table 4 along with the assigned risk rating.
TABLE 4
SUMMARY OF FACTORS THAT POTENTIALLY AFFECT
THE RISK OF SAFETY RELATED EVENTS
Factor or Issue
Risk Rating
Median is somewhat narrow (46-52 feet), no barrier
and crossable
E
Pavement markings on west section are faded
B
Delineators posts are missing
B
Lane drop signage - in westbound direction at Main
Street first sign is located inside curve and may not
be noticed
D
Merge warnings are “hidden” in some locations
C
Inside shoulder in east section is less than 2 feet
C
Some merge areas or acceleration lanes may be
shorter than desirable – markings are inadequate for
some locations
C
High speeds
C
Some ponding in left shoulder WB between Mill Street
on-ramp and Route 57 WB on ramp from Route 75
B
As indicated in Table 4, the existing median condition being relatively narrow and
determined to be highly crossable was rated with a risk rating of ‘E’. With the median
width approximately 46 to 52 feet and the observed volumes are between 24,000 and
possibly as high as 36,000, a barrier can be considered based on the median barrier
guidelines. The experience in recent reported crashes showed that more than half of the
median related crashes were classified as cross-median crashes. Other items that could
contribute to an event that results in a median entry and possible crossing include: the
visibility of the median or improper lane-changing where the noted faded pavement
markings, lack of flexible delineator posts along the median edge, narrow inside
shoulders exist, the less than ideal advance warning signage for on-ramps (i.e. Garden
Street eastbound) and the westbound lane-drop at Route 159. The specific factors
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Route 57 Agawam Road Safety Audit
pertaining to faded, markings and delineator posts were assigned a risk factor of ‘B’.
The narrow inside shoulder factor was assigned a rating of ‘C’. The lane drop with its
specifically related signage issue was assigned a ‘D’ risk rating.
In addition, the identification of acceleration or deceleration lanes is inconsistent and in
some locations not clearly demarcated. It also appeared that acceleration lanes might
be shorter than desirable. This could be a perception due to the lack of markings, which
may also be related to the width of shoulders that is carried through the interchange. A
risk rating for this factor was assigned a ‘C’.
Based on spot observations of the RSA team members and discussions with the State
Police, high travel speeds are a significant contributing factor to improper lane changing,
losing control of the vehicle and median entries. With the exposure relatively low for the
type of highway being evaluated but considering the characteristics of the median, a risk
factor of ‘C’ was assigned to this factor.
Finally, it was noted that there was some ponding of water occurring in the section west
of Route 75 on the inside shoulder. It was not apparent that the main travel lanes
experienced the same condition. While the ponding could affect driver control in certain
sections, given that it occurs in the shoulder, there would be a lower likelihood that the
condition would cause the 1st event of a crash in which the motorist entered the median.
This factor was assigned a ‘B’ rating.
Once the factors were identified, suggested actions were identified that are intended to
reduce the median cross-over crashes on the Route 57 and enhance the overall safety
along the highway. Given that this RSA program is focused on cross-median crashes,
the initial action evaluated was the consideration of installing median barrier. The
following paragraphs include a discussion pertaining to the issues and the potential
actions to consider for implementation.
•
Consideration of a Median Barrier
One of the more significant actions to be considered is to install median barriers in the
current “open” areas. A barrier can be considered when there is a higher than desirable
chance or a greater risk for median cross-over crashes to occur and that have or could
result in fatalities and/or a high proportion of injury related crashes. In addition, a barrier
could be considered when the consequences or severity of a crash are worse than if the
barrier were in place.
Factors that generally come into play in deciding on whether a median should be
installed involve the following:
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




High volumes and speeds
Truck volumes and mix
Narrow median
History of cross-median crashes
High risk of catastrophic event
These items have been reviewed relative to the Route 57 section under study. Figure
10 presents a review of the corridor in relation to the median warrant criteria presented
in the AASHTO RDG4. As can be seen in the diagram, with the median (as measured
from edge line to edge line) is approximately 46 to 52 feet and volumes of 24,000
vehicles on an average day in the west section, the intersection of the two items is in the
area of the chart where a barrier is largely considered in the category. In the east
section with estimated volumes at 36,000 ADT, the intersection point in the chart is still
in the “considered” area though more on the boundary between the two categories.
In addition to the chart and related warrant criteria, which is a guideline, further
consideration was given to the following:
ƒ
ƒ
ƒ
A high proportion (>50%) of cross-median crashes as a percent of total
median crashes over the three (3) year period,
High speeds, and
High proportion of injury related crashes.
Consequently, based on the analysis of the data, the field drive-thru and discussion of
the conditions by the RSA team members, it is suggested that a median barrier be
installed in the sections of the route that are currently open and “crossable”. This will
represent approximately 3.9 miles of barrier to be installed. The selection of the barrier
is discussed in the next section.
A. Barrier Selection
There are a number of barrier types that can be considered in addressing the median
cross-over crashes. These include the following:
♦
♦
♦
♦
4
Weak post W-Beam
Box Beam
Generic Low Tension Cable
High Tension Cable Barrier
♦ Strong post W-Beam
♦ Thrie Beam
♦ Concrete (Jersey)
American Association of State Highway and Transportation Officials, Roadside Design Guide,
Washington, D.C., 2002, Chapter 6 Update 2006.
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80
AVERAGE DAILY TRAFFIC
(thousands)
70
BARRIER
RECOMMENDED
60
BARRIER
CONSIDERED
50
40
BARRIER
OPTIONAL
East Section (est.)
30
West Section
20
10
0
0
10
20
30
40
MEDIAN WIDTH
(feet)
Note: Volume location was west of Main Street interchange. Volume
is expected to behigher east of Main Street interchange.
50
60
70
Est. Traffic Volumes
East
36,000
West 24,000
Analysis of Median Barrier Warrant
Route 57 Road Safety Audit
Agawam, Massachusetts
MS Transportation Systems, Inc.
Framingham, Massachusetts
Figure 10
Route 57 Agawam Road Safety Audit
In deciding on the type of barrier, recommended guidelines in selection are included in
Table 5 taken from the AASHTO Roadside Design Guide5.
TABLE 5
CRITERIA FOR BARRIER SELECTION
Criteria
Comments
1. Performance Capability
Barrier must be structurally able to contain and redirect
design vehicle.
Expected deflection of barrier should not exceed available
deflection distance.
Slope approaching the barrier and distance from traveled
way may preclude use of some barrier types.
2. Deflection
3. Site Conditions
4. Compatibility
5. Cost
6. Maintenance
A. Routine
B. Collision
C. Material Storage
D. Simplicity
7. Aesthetics
8. Field Experience
Barrier must be compatible with planned end anchor and
capable of transitioning to other barrier systems (such as
bridge railings).
Standard barrier systems are relatively consistent in cost,
but high-performance railings can cost significantly more.
Few systems require a significant amount of routine
maintenance.
Generally, flexible or semi-rigid systems require
significantly more maintenance after a collision than rigid
or high-performance railings.
The fewer different systems used, the fewer inventory
items/storage space required.
Simpler designs, besides costing less, are more likely to
be reconstructed properly by field personnel.
Occasionally, barrier aesthetics are an important
consideration in selection.
The performance and maintenance requirements of
existing systems should be monitored to identify problems
that could be lessened or eliminated by using a difference
barrier type.
Source: AASHTO, Roadside Design Guide, 2002, Chapter 5 Roadside Barriers.
From a cost and aesthetic perspective, the cable (flexible) barrier has its advantages
over the various guardrail systems or concrete barrier. The median slope and/or
recovery area also affects the use and placement of any barrier including guardrail. With
regard to the cable barrier, the RSA team has discussed two primary cable alternatives
noted below. In addition to the cable barrier systems, team members also suggested
that guardrail be considered in the evaluation. The alternative types of guardrail were
reviewed for potential application on this route. Considerations included the volume of
traffic, relative amount of truck traffic and travel speeds. Based on these, the most
5
American Association of State Highway and Transportation Officials, Roadside Design Guide,
Washington, D.C., 2002, Chapter 6 Update 2006.
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applicable types of guardrail for this route include the W-beam with strong post or the
strong post thrie-beam. These rails are appropriate for high speed highways and high
volumes with a relatively high proportion of truck traffic. Costs for each are similar. The
weak post W-beam and box beam can be eliminated due to the slope and type of
highway. The concrete barrier would generally be applicable in urban sections with
limited median widths available. As a result, the median barrier options that are valid for
consideration for Route 57 in this section are the cable barrier and strong post guard rail.
Maintenance issues are also an important consideration in decisions regarding median
barrier installations. The maintenance issues that are of concern include:
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
Barrier hits per mile
Frequency of hits
Cost recovery
Cable downtime
Repair effect on traffic
Maintaining tension
Final selection of the barrier type should be based on the costs, the ability to maintain a
recovery zone, likely maintenance or repair requirements, and compatibility with future
planned widening. The key points of the cable barrier or guardrail are summarized
below.
Cable Barrier
While the low tension generic cable system has been in existence for more than 50
years, most of the recent cable system research and installation is focused on the high
tension systems. There are currently six (6) manufacturers with systems approved by
the Federal Highway Administration (FHWA) for use under certain conditions. There are
3-rope or 4-rope cable systems as shown in the following two photographs.
4 – Rope Brifen System
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3 Cable CASS System
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Route 57 Agawam Road Safety Audit
This barrier can be installed on slopes of 6:1 or flatter with little constraint on placement.
There are certain systems (Brifen and Gibraltor 4 rope) that have also been approved for
slopes as steep as 4:1. The cable can usually be installed sufficiently away from the
paved surface so as to maintain some level of clear zone and to minimize ‘hits’. With
post spacings at approximately 10 to 16 feet, maximum deflection is expected to be in
the 11-12 foot range. The cable barrier is designed to “catch” the errant vehicle and
absorb the force of the hit and more slowly bring the vehicle to a stop. With this, the
severity of the crash has been shown to be lower than the alternative barrier types.
Guardrail
Typically, guardrail is used where steep slopes or minimal recovery zones exist within
close proximity to the pavement surface. Guardrail is also utilized where the median
width is narrow and low deflections are required. In addition, guardrail can be placed in
the median where slopes are 10:1 or flatter. With the guardrail placed within several feet
of the pavement edge, the clear zone (or recovery area) would be eliminated at least on
one side. Deflection with the thrie-beam rail is in the 2 to 3 foot range. One consequence
of the guardrail placed at the edge of pavement is that there is a “bounce off” effect
when struck by a vehicle. This can potentially increase the number of vehicles affected
in the crash.
Per mile costs of the two basic types of median barrier treatment to be considered are
summarized in Table 6.
TABLE 6
COMPARISON PER MILE COSTS
Cable vs. Guardrail
Costs/Mile
Cable
$144,000
Thrie beam
$213,000
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Recommendations
As a result of the RSA analysis and team input, a set of recommendations have been
identified and are summarized in Table 7. These actions are intended to reduce the risk
of median entry, eliminate the chance of cross-median crashes as well as reduce the
severity of all crashes and improve the overall safety condition of this section of Route
57 in Agawam. Identified in the table in addition to the risk factor and recommended
action are the estimated costs and potential timeframe (i.e. short (0-1 year), medium (1-3
years) and long (>3 years)).
The assessment of the RSA team for the Route 57 section between Route 5 and Route
187 resulted in a determination that installing a median barrier was a recommended
action to take for the corridor. The objective of this action would be to eliminate median
cross-over events. More than half of the reported median crashes were further
categorized as cross-median events. The cable median barrier is the most cost-effective
barrier to install in this section when compared to the other barrier options. If placed
near the center of the median, a recovery area of approximately 20 to 25 feet +/- should
remain and the maintenance issues would be expected to be minimal based on the
experience of other installations around the country. The cost of this action is estimated
to be $560,000 assuming an installation for approximately 3.9 miles.
Another major action recommended by the RSA team is to install new overhead static
signage for enhanced warning and information. These are to address the westbound
lane drop at the Route 159 exit. The new sign (or set of signs) would replace the
roadside sign that currently exists off the road and was noted as difficult to see given the
highway curve and vegetation in the immediate area. The estimated cost for these new
signs are $30,000 and is considered a short-term to medium term action. One option is
to install two new overhead signs with similar legends. The first would be located one
mile prior to the exit while the second sign would be placed ½ mile prior to the exit. A
third sign to supplement these would be a roadside sign indicating “Windsor Locks CT”
and would be installed after the second overhead sign. Figure 11 provides an example
of the legends for signs A and B in relation to the lane drop.
Improved advance warning signage for the eastbound Garden Street on-ramp is also
suggested to address the visibility and awareness issues at this merge that are largely
created in part by the roadside slope and vegetation, the alignment of the route at that
location and the closeness of the Route 75 exit just beyond the on-ramp. An overhead
sign would provide a high level of visible information to the approaching motorist
although be a high cost item. Alternatively, a large roadside sign could also be used and
provide as a short term solution and a lower cost (see Figure 11).
MS Transportation Systems, Inc.
Page 18
Route 57 Agawam Road Safety Audit
TABLE 7
SUMMARY OF RECOMMENDATIONS
Risk Factor
Risk
Rating
E
ƒ
Pavement markings on west
section are faded
B
ƒ
Delineators posts are
missing along median
B
ƒ install new
delineator posts –
approx. 18,500 feet
$4,000
ƒ short term
Lane drop signage - in WB
direction at Main Street first
sign is located inside curve
and may not be noticed
D
ƒ Install overhead
signs (2) system
ƒ Install one roadside
sign for more
information
$40,000
ƒ medium
term
ƒ medium
term
Merge warnings are
“hidden” in some locations
C
ƒ install roadside
advance warning for
prior merge to
Garden Street EB
on-ramp
$5,000
ƒ short term
Inside shoulder in east
section is less than 2 feet
C
ƒ widen inside
shoulder to 4 feet in
eastern section
$1.3M
ƒ long term
Some merge areas or
acceleration lanes may be
shorter than desirable –
markings are inadequate for
some locations
C
ƒ install YIELD signs
on entrance ramps
ƒ improve markings of
acceleration lanes
ƒ increase length of
acceleration lanes
$2,500
ƒ short term
TBD
ƒ long term
TBD
ƒ long term
High speeds
C
ƒ increase
enforcement
TBD
ƒ short term
Some ponding in left
shoulder WB between Mill
Street on-ramp and Rte 57
WB on ramp from Rte 75
B
ƒ address drainage
TBD
ƒ medium
term
Median is somewhat narrow
(46-52 feet), no barrier and
crossable
MS Transportation Systems, Inc.
Recommended
Action
Install permanent
barrier
Install new markings
Estimated
Cost
$560,000
TBD
(low)
$5,000
Estimated
Timeframe
ƒ medium
term
ƒ
short term
Page 19
Main Street NORTH
W. Springfield
159 SOUTH
Agawam Ctr
EXITS 1 MILE
ONLY
OVERHEAD SIGN A - Route 159
(Place one mile and 1/2 mile prior to Exit)
Windsor Locks CT
SECOND RIGHT
ROADSIDE SIGN B - Route 57
Westbound 1/2 prior to Route 159 exit
CAUTION
MERGING TRAFFIC
AHEAD
ROADSIDE SIGN C - Route 57
Eastbound prior to Garden Street EB on-ramp
CONCEPTUAL ONLY NOT TO SCALE
Potential Sign Legends
Route 57 Road Safety Audit
Agawam, Massachusetts
MS Transportation Systems, Inc.
Framingham, Massachusetts
Figure 11
Route 57 Agawam Road Safety Audit
The pavement markings that are faded in the western section are expected to be
replaced as part of the scheduled maintenance but the markings for the acceleration and
deceleration lanes could be enhanced at several of the interchange ramps and should
be consistently applied through the section. This would include adding dotted lines as
an extension of the lane line, for example. The current MUTCD depicts options with
dotted lines for deceleration lanes and weave sections (see Appendix for diagrams).
The upcoming revised MUTCD is expected to include dotted lines for acceleration lanes
as well.
Other actions to improve the motorist guidance include installation of new flexible post
reflective delineators along the median and the additional advance warning signage of
on-ramps.
Increased enforcement of speeds and driver behavior is also recommended. This will
likely require additional manpower and funding.
MS Transportation Systems, Inc.
Page 21
Route 57 Agawam Road Safety Audit
Appendix
•
•
•
•
•
•
MS Transportation Systems, Inc.
RSA Meeting Agenda
RSA Attendees List
Median Crash Diagram
Crash Data
Traffic Volume Data
Sample Lane Markings
Page 22
Road Safety Audit
Agawam – Route 57
Meeting Location: MassHighway District 2 Office
811 North King Street, Northampton
Wednesday, June 18, 2008
11:00 AM – 12:30 PM
Type of meeting:
Cross Median – Road Safety Audit
Attendees:
Invited Participants to Comprise a Multidisciplinary Team
Please bring:
Thoughts and Enthusiasm!!
11:00 AM
Welcome and Introductions
11:15 AM
Introduction to Road Safety Audits and Cross Median Crashes
11:30 AM
Review of Site Specific Material
• Crash & Volume Summaries– provided in advance
• Existing Geometries and Conditions
• Video and Images
12:00 PM
Completion of RSA
• Identification of Safety Concerns – using RSA Prompt List as a guide
• Identification of Possible Countermeasures
12:30 PM
Adjourn for lunch – but the RSA has not ended
Instructions for Participants:
• Before attending the RSA on June 18th participants are encouraged to drive
Route 57 in Agawam from the Route 5 Rotary to Garden Street and
complete/consider elements on the RSA Prompt List with a focus on safety factors
affecting cross median 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.
ROAD SAFETY AUDIT MEETING
Route 57 Agawam - June 18, 2008
MassHighway District 2 Offices, Northampton MA
Attendance List
Name
Agency/Dept.
Email
Bill Scully
MS Transportation Systems, Inc.
[email protected]
Lt. Steven Hughes
State Police/Springfield
413-736-8390
Sam Gregorio
MassHighway - District 2 Traffic
[email protected]
Xian Chen
MassHighway
[email protected]
Bao Lang
MassHighway
[email protected]
Gary Roux
PVPC
[email protected]
Khyati Parmar
PVPC
[email protected]
John Donoghue
MassHighway
[email protected]
Hal Piligian
MassHighway
[email protected]
Ken Wanar
MassHighway
[email protected]
Trung Vo
MassHighway
[email protected]
William goulet
MassHighway
Robert Fay
MassHighway
[email protected]
Lathryn Cook
MassHighway
[email protected]
Lyris Liautaud
MassHighway
[email protected]
MS Transportation Systems, Inc.
±
T
EE
Route 57 Median Crashes
RO
W
O
CO
LE
Y
ST
RE
E
R
PE
R
ST
T
9
10
11
7
3
MILL S
M
RA
P -R
T7
O
5T
5
RT
B
7W
5
4
8
6
T RE E T
)
"
159
2
SCHOOL STR EET
)
"
AGAWAM
57
ET
)
"
Legend
Type of Median Crash 2004-2007 *
Major Roads
Cross Median, Non-Fatal Crash
Median, Non-Fatal Crash
G
AR
D
Municipal Boundary
EN
ST
R
TR
T
EE
SU FFIELD ST
RE ET
MS
EL
LE
ON
AR
D
Interstate
Principal Arterial
E
SILV
R
EET
S TR
Minor Arterial
Collector
EE
T
Local
* 2007 crash file has not yet been closed.
0
0.1
0.2
0.3
MAIN
1
S T RE
75
Miles
0.4
AD
AM
S
S
EE
TR
T
ST
RE
ET
MASSACHUSETTS HIGHWAY SAFETY DIVISION
CRASH SUMMARY
ROADWAY:
RT 57
STUDY PERIOD:
NO.
1/1/2004
CRASH NUMBER
TO
CRASH DATE
12/31/2007
CITY:
AGAWAM
LOCATION:
NEAR RT 75
TRAVEL
LIGHT
WEATHER
ROAD
REASON FOR
VEHICLE
MEDIAN OR CROSS
DRIVER CONTRIBUTING
CRASH
LANES
CONDITION
CONDITION
SURFACE
RUNNING OFF ROAD LEFT
MOVEMENT
MEDIAN CRASHES
CAUSE
SEVERITY
1
2148227
1/23/2007
WB
Daylight
Clear
Dry
Vehicle rear wheels skidded out and caused the vehicle to spin
W/B Travel Lane to E/B Grassy Area
Cross Median
Failure to keep in proper lane
Non-Fatal Injury
2
2011597
12/9/2005
EB
Daylight
Snow
Snow
Vehicle run off road left and hit another vehicle head-on
E/B Travel Lane to W/B Travel Lane
Cross Median
Failure to keep in proper lane
Non-Fatal Injury
3
2055303
4/9/2006
WB
Dark - Lighted
Clear
Dry
Lost control of vehicle, crossed median and overturned
W/B Travel Lane to E/B Travel Lane
Cross Median
Exceeded Speed Limit and Drugs
Non-Fatal Injury
4
2011505
12/23/2005
EB
Dark - Not Lighted
Cloudy
Dry
Vehicle hit deer
Travel Lane to Median
Median
No Improper Driving
Property Damage Only
5
2071048
4/18/2006
WB
Daylight
Clear
Dry
Driver had a diabetic reaction, passed out and the vehicle overturned
Travel Lane to Median Guardrail to Trees in the Median
Median
Illness
Property Damage Only
6
2071041
4/20/2006
EB
Dark - Not Lighted
Clear
Dry
Lost control of vehicle, hit another vehicle in the rear and overturned
E/B Travel Lane to W/B Travel Lane
Cross Median
Exceeded Speed Limit and Alcohol
Non-Fatal Injury
7
2226087
8/2/2007
WB
Dawn
Clear
Dry
Driver inattention caused vehicle to overturn
Travel Lane to Median Ditch
Median
Inattention
Property Damage Only
8
1750334
6/23/2004
EB
Daylight
Clear
Dry
Lost control of vehicle
E/B Travel Lane to W/B Right Breakdown Lane
Cross Median
Exceeded Speed Limit
Property Damage Only
9
1781083
9/12/2004
WB
Dark - Not Lighted
Clear
Dry
Fallen asleep and vehicle went off to the median
W/B Travel Lane to E/B Right Guardrail
Cross Median
Fatigued/Asleep
Property Damage Only
10
2010023
6/12/2005
WB
Dark - Not Lighted
Clear
Dry
Vehicle failed to negotiate a curve
Travel Lane to Median Guardrail
Median
Failure to keep in proper lane
Property Damage Only
11
2010058
6/19/2005
WB
Daylight
Clear
Dry
Traffic slowed due to six flags volume and vehicle hit another vehicle in the rear
Travel Lane to Median Guardrail
Median
Followed too closely
Non-Fatal Injury
LIGHT CONDITION
WEATHER CONDITION
ROAD SURFACE
MEDIAN OR CROSS MEDIAN
TOTAL NO.
DAYLIGHT
DAWN
DARK - LIGHTED
DARK - NOT LIGHTED
CLEAR
CLOUDY
SNOW
DRY
SNOW
MEDIAN
CROSS MEDIAN
11
5
1
1
4
9
1
1
10
1
5
6
100%
45%
9%
9%
36%
82%
9%
9%
91%
9%
45%
55%
ILLNESS
INATTENTION
FATIGUED/ASLEEP
DRIVER CONTRIBUTING CAUSE
CRASH SEVERITY
PROPERTY
NON-FATAL
NO IMPROPER
EXCEEDED SPEED LIMIT
EXCEEDED SPEED
EXCEEDED SPEED
FOLLOWED TOO
DAMAGE ONLY
INJURY
DRIVING
AND ALCOHOL
LIMIT AND DRUGS
LIMIT
CLOSELY
FAILURE TO KEEP IN PROPER LANE
6
5
1
1
1
1
1
3
1
1
1
55%
45%
9%
9%
9%
9%
9%
27%
9%
9%
9%
2007 CRASH INFORMATION ARE NOT COMPLETE
CRASH SUMMARY IS BASED ON CRASH REPORTS WITH STATE POLICE NARRATIVES
RT-57, West of RT 75 (Suffield Street) 08/01/2007
Eastbound Westbound
Direction
Direction
TOTAL
Start time
12:00 AM
56
128
184
1:00 AM
40
71
111
2:00 AM
58
52
110
3:00 AM
49
36
85
4:00 AM
92
67
159
5:00 AM
298
294
592
6:00 AM
749
573
1,322
7:00 AM
1,207
741
1,948
8:00 AM
1,103
584
1,687
9:00 AM
735
519
1,254
10:00 AM
543
418
961
11:00 AM
562
540
1,102
12:00 PM
607
583
1,190
1:00 PM
580
579
1,159
2:00 PM
647
787
1,434
3:00 PM
936
944
1,880
4:00 PM
935
1,132
2,067
5:00 PM
947
1,120
2,067
6:00 PM
655
658
1,313
7:00 PM
503
491
994
8:00 PM
403
470
873
9:00 PM
334
369
703
10:00 PM
236
319
555
11:00 PM
163
189
352
Daily Total
12,438
11,664
24,102
Eastbound Direction
Westbound Direction
1,400
1,200
1,000
800
600
400
200
PM
:0
0
PM
10
8:
00
PM
6:
00
PM
PM
Time of Day
4:
00
PM
2:
00
:0
0
AM
12
:0
0
AM
10
AM
8:
00
AM
6:
00
AM
4:
00
2:
00
:0
0
AM
0
12
Hourly Volume (Number of Vehicles)
Directional Traffic Volumes along RT-57, West of RT-75, Agawam
Wednesday, August, 01, 2007
a-Parallel
deceleration lane
b-Tapered
deceleration lane
Neutral area
Optional
chevron
markings
Channelizing
lines
Theoretical gore
point
Channelizing
lines
Broken lane
markings for
one-half of
full-width
deceleration
lane
Optional
dotted
extension
of lane
line
Legend
Direction of
travel
Source: MUTCD
Potential Pavement Markings Off-Ramp Deceleration Lanes
NOT TO SCALE
MS Transportation Systems, Inc.
Framingham, Massachusetts
Neutral area
Optional chevron
markings
Theoretical gore
point
Broken or dotted lane line
markings for full length of
acceleration/deceleration lane
Channelizing
lines
Legend
Direction of
travel
Source: MUTCD
Example of Channelizing Line Applications
for Entrance-Exit (Weave) Ramp Markings
NOT TO SCALE
MS Transportation Systems, Inc.
Framingham, Massachusetts
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