ROAD SAFETY AUDIT
MAJOR HIGHWAY MEDIAN
CROSS-OVER CRASHES
I-95 DANVERS-TOPSFIELD
Prepared for
Massachusetts Highway Department
Prepared by
MS Transportation Systems, Inc.
Framingham, Massachusetts
March 2009
ROAD SAFETY AUDIT
MAJOR HIGHWAY MEDIAN
CROSS-OVER CRASHES
I-95 DANVERS-TOPSFIELD
FINAL REPORT
March 2009
Prepared for
Massachusetts Highway Department
Prepared by
MS Transportation Systems, Inc.
Consulting Engineers and Planners
300 Howard Street, P.O. Box 967
Framingham, Massachusetts 01701
Tel: (508) 620-2832 Fax: (508) 620-6897
www.mstransportationsystemsinc.com
I-95 Danvers-Topsfield Road Safety Audit
TABLE OF CONTENTS
Page
INTRODUCTION
1
RSA PROCESS
3
ANALYSIS
8
SUMMARY OF RSA FINDINGS/POTENTIAL ACTIONS
13
RECOMMENDATIONS
22
APPENDIX
26
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INTRODUCTION
Lane departure crashes are one of the primary fatal crash types in Massachusetts. The
Commonwealth exceeds the national average for 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 (MHD) 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 that could affect
the safety risk. During the audit, the RSA team works to identify opportunities for
enhancing safety and to recommend specific enhancements intended to reduce median
cross-over crashes and improve the overall safety along the highway.
An RSA was conducted for the I-95 in Danvers and Topsfield as part of this overall
effort. The roadway section under study, shown in Figure 1, was between Interchange
(approximately 1,000 south of No. 49) and Interchange No. 53 a distance of 7.4 miles.
This section had experienced a number of median related crashes that included several
reported cross-over incidents.
The purpose of this I-95 Danvers-Topsfield RSA was to review current safety
characteristics on the highway section under study, identify potential risk factors and to
recommend a set of actions to enhance the safe operation of the highway section under
study.
Recommendations contained in this report reflect the overall consent of the RSA team
and do not necessarily reflect the official opinions of MassHighway.
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Middleton
95
95
95
Interchang
e 51
Interchang
e 52
Interchang
e 53
Topsfield
Interchang
e 49
Interchang
e 50
Danvers
W
I-95 Road Safety Audit
Danvers-Topsfield, Massachusetts
S
N
E
Project Location
Figure 1
I-95 Danvers-Topsfield Road Safety Audit
RSA PROCESS
In conducting the RSA, the overall procedures outlined in the Median Cross-Over RSA
Guideline Report1 with some modifications given the characteristics of the facility being
reviewed. The process included identifying RSA team members; conducting field visits;
holding a RSA team meeting and then completing an assessment of the data and
findings from the field visits and meetings to render recommended actions for
MassHighway to consider. Data including recent traffic volume data, summary crash
records for the 2004-2007 period, detailed crash reports of cross-over crashes, and
available record highway plans were obtained and reviewed by the RSA consultant. In
addition, maintenance records related to the cable barrier since late 2006 were provided
by the Department. Field visits were conducted by the RSA team members. A video
recording of the sections under study was taken by the RSA Consultant. The site visits
were completed prior to the RSA team meeting that was held on July 31, 2008 at the
MassHighway District 4 offices. At that 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 provided input and discussed the key items
noted in the field and that were listed on the RSA Median Cross-Over Prompt List.
Issues and concerns were noted. Following the RSA meeting, the RSA consultant
compiled the information, completed the analysis and circulated the draft report.
•
RSA Team
The following were members of the I-95 Danvers-Topsfield Road Safety Audit:
Lyris Liautaud, MassHighway Design
Bonnie Polin, MassHighway Safety
Kaiyan Jiang, MassHighway Design
Efi Pagitsas, Boston Region MPO
Andrew Hirshfield, MassHighway Traffic
Tim White, Federal Highway Admin.
•
Paul Fletcher, Mass State Police “A”
Brett Loosian, MassHighway District 4 Maint.
John Gregg, MassHighway District 4 Traffic
Lisa Schletzbaum, MassHighway Safety
William J. Scully, MS Transportation Systems
(RSA Consultant)
RSA Team Meeting
The RSA team meeting took place on July 31, 2008 at the District 4 offices in Arlington.
The team included engineers, planners and a representative from the State Police
barrack that has jurisdiction of I-95 in Danvers and Topsfield. Represented were
MassHighway (Boston and District), as well as the State Police. A list of the team
members at the meeting with contact information is included in the Appendix. As stated
1
MS Transportation Systems, Inc., Road Safety Audits, Median Cross-Over Crashes, Audit Guidelines, Prepared for
MassHighway, October 2007.
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previously, overall characteristics and conditions of the study section were presented. A
video and still photographs were reviewed by the RSA team and a discussion of the
potential safety opportunities for enhancement followed. The key items discussed at
that meeting included the following:
 While the overall geometric design of the highway appears efficient and
results in a comfortable drive, the condition also contributes to high speeds.
The RSA team did not have data available, but the Mass State Police stated
that the 80-85 mph range was likely.
 There are two segments in the study section that contain horizontal curves
and downgrades following long straight sections. These are: northbound on
approach to Interchange No. 51; and the southbound approach to
Interchange No. 49. In these two segments, RSA team members noted that
crashes occurred in these areas in which a combination of the speeds,
geometry condition and level of guidance appear to have led to “missing” the
curve and entering the median.
 There was further discussion that the data currently available to the RSA
team not being accurate enough to clearly cite that the curves are definitively
the problem, although that is the perception and recollection.
 Sun glare is another problem that affects visibility at different times of the day.
While there was clear evidence of a substantial number of median cross-over crashes
(41% of the total median related crashes), there was much discussion of whether a
barrier should be considered given the average width of the median in the study section.
•
Analysis Procedures
As previously indicated, the RSA analysis generally followed the procedure described in
the previously referenced 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
Obtaining and reviewing crash and other traffic characteristic data and
available record plans.
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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•
•
•
Conducting site reconnaissance and collecting a current record of condition
via photos and video,
Identifying opportunities for enhancement, and
Identifying and evaluating 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
guidelines of FHWA 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.
ESTIMATED
Exposure
high
medium
high
medium
low
high
Probability
high
high
medium
medium
high
low
low
medium
low
medium
low
low
TABLE 1
FREQUENCY RATING
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
Frequent
Occasional
Infrequent
Rare
Severity Rating
Low
Moderate
High
Extreme
C
B
A
A
D
C
B
A
E
D
C
B
F
E
D
C
Source: FHWA RSA Training Workshop
Crash Risk Ratings:
A: minimal risk level
B: low risk level
C: moderate risk level
•
D: significant risk level
E: high risk level
F: extreme risk level
RSA Field Audit
Field audits were conducted by the RSA team members between on or before July 31,
2008. In general, the field visits included “drive-throughs” in each direction of the study
section noting physical conditions and the “feel” of the driver. The Prompt List
developed as part of the RSA process was used as a guide. The prompt list is included
in the appendix for background. The field audits showed the following:
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There are four travel lanes per direction within the project area.
With the exceptions noted below, the overall alignment of the study
section can be characterized as gentle with several horizontal curves.
While overall this portion of I-95 has a gentle overall alignment, there are
two curves that affect the degree of driver comfort, the southbound curve
south of Interchange No. 50 is slightly discomforting to motorist in high
speed lane – a similar feeling occurs in the northbound direction south of
Interchange No. 51.
North of Interchange No. 51, the highway is fairly tangent and level
providing a high degree of driver comfort.
The median varies in width and slope through out study section from
gentle depressed slope to relatively steep east to west downgrade.
Inside shoulders are 2 to 3 feet in width with a rumble strip in place.
Rumble strips also exist in outside shoulder.
Recessed reflectors exist in lane lines.
Pavement surface is in good condition.
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ƒ
ƒ
ƒ
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Pavement markings are in good condition.
There are no delineator posts or other guidance provided along the
median.
Speeds are posted at 65 miles per hour.
There was physical evidence (i.e. tire tracks) of several median entries
noted.
In general, it was noted that the drive along the study section even during
peak periods is generally free with four lanes of capacity available.
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ANALYSIS
In completing the RSA of I-95 in Danvers-Topsfield, findings were compiled from the
field audits, the review of the data input provided by team members. The following
sections summarize the results from each of the key components of the assessment.
I-95 in the Danvers-Topsfield area is a major north-south highway serving the
communities to the north of Boston. The section under study is approximately 7.4 miles
long consisting of 4 travels lanes per direction with 10 foot outside shoulders. There are
five (5) interchanges located in the study section. Interchange No. 53 is actually in
Boxford. Inside shoulders were noted in the field as being between 1 and 3 feet in
general depending on location. Rumble strips are present in both shoulders. There is no
other delineation of the median other than the inside edge line. Reflectorized markers
(slotted in pavement) have been installed in the lane lines.
The roadway alignment in the study section is largely straight including a nearly 2.0 mile
long tangent section. Two large radius horizontal curves on the north (south of
Interchange 51) and south (south of Interchange 50) exist at the ends of that 2 mile
tangent section. The overall pavement section appears to be in good condition as well
as the markings currently in place.
Most of the median is “open” with 6.3 miles or 85% of the total 7.4 mile long study
section in this category. The open median width was determined along the study section
and measured for the most part between 80 and 88 feet. South of Interchange No 49,
the median narrows to approximately 35 feet. Field visits identified evidence of median
entries along the study section, particularly noted between Interchanges Nos. 49 and 51.
Approximately half of the open median length is in this particular area.
Figure 2 – Median Section of I-95
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The median is a depressed design for most of the corridor section. For the most part,
the slope of the median appears to be 6:1 or flatter, which would be consistent with the
typical section plans that were the basis of the initial design. In several areas, there is a
small elevation differential between the northbound and southbound directions. In these
areas, the median has a somewhat longer straight down slope from one side to the other
but maintains the depressed design close to the center of the median. There are several
overpasses that exist along the study section and the columns supporting the bridge
crossings (i.e. Route 1) are not all protected from the driving public with the placement of
guardrail. The columns may in fact be outside the 30 foot clear zone but still pose a risk
as the median has been determined to be crossable. The pavement edge along the
median appeared adequate with no significant drop off noticeable.
Posted speed limits in the study section were noted at 65 miles per hour (mph). General
observations by the State Police suggest that speeds in the 80-85 mph range would not
be unlikely. The high speeds along with the combined long tangent, downgrade sections
prior to the curves appear to be a contributing factor to higher risks.
Figure 3 – Northbound on I-95 approaching Route 62 Interchange
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Figure 4 – Example of inside shoulder
with rumble strip
Data available as part of the
MassHighway crash records system
indicated that between 2004 and 2007,
there were 27 reported crashes related
to the median. Of the 27, 41% or 11
were
identified
as
cross-median
crashes. The 11 cross-median crashes
Figure 5 – Approaching curve in Northbound
direction prior to Interchange No. 49
resulted in personal injuries in 82% of
the crashes. There was one fatal crash
reported which was also a cross-median
crash. The fatality occurred south of
Interchange No. 51 with a vehicle in the
northbound direction initiating the event.
In most crashes, the cited cause for the
cross-median crashes were either the
driver “swerving”, reckless, failing to
stay in proper lane or speed. Five
(19%) of the total median related
crashes involved “falling asleep or
fatigue”, while six weather related
crashes (22%) with wet road surface
were noted.
Three (3) of the crossmedian crashes occurred during dark
conditions. There was no significant
directional
difference
in
reported
crashes.
Figure 6 - Unprotected bridge columns in
median at Route 1 Overpass
Conditions that were noted in the crash reports varied. There were no predominant
factors or causes for the crashes. Included were inattention or equipment problems in
addition to the previously noted causes.
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Traffic volumes collected in 2007 show I-95 in the project area carrying approximately
80,000 vehicles per day. Peak hour flows in the peak direction as high as 5,300
vehicles. As shown in Figures 8 and 9, there is both a distinct peaking pattern of volume
on I-95 as well as a directional flow pattern that clearly reflects commuter activity to and
from Boston and its surrounding areas. Available truck volume data for I-95 in the
project area indicated that truck volume over the course of the day represents 5% of the
total volume equating to approximately 4,000 trucks on an average weekday.
It was also noted by the RSA team that a “reduced salt area” exists between the Route 1
interchange (Exit 50) to Route 133 north of the study section. Signs were not observed
in the study area.
Figure 7 - Small elevation differential between directions
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Figure 8 – I-95 Traffic Volumes North of Route 1
Figure 9 – I-95 Traffic Volumes North of Route 62
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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 I-95 in the
Danvers-Topsfield area 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 “open” throughout project area except for approaches to
overpasses and the protection of some structures
E
Geometry of curves approaching end of long tangent (long straight
section of highway north of Int. 49 (SB direction) and south of Int.
51 (NB direction) prior to curves
E
Difference in elevation in areas of curves – SB south of Int. 50 and
NB south of Int. 51 (relates to curve geometry factor also)
E
Median is not delineated
D
High travel speeds exist on section
C
Inside shoulder is narrow
D
Driver fatigue affected by long, straight road section
D
Sun Glare – SB south of Int. 51 in AM and NB north of Int. 50 in
PM
B
Some bridge columns unprotected – at Route 1 overpasses
B
Low salt area - not signed
B
Given the high traffic volume on the study section and the high number of cross-median
events (3-4 per year) the “open” median factor was assigned a risk factor of ‘E’.
Although the width would appear sufficient to contain the errant vehicles, the speeds
combined with the geometry (i.e. elevation differences, horizontal curves), the data
clearly shows that once a motorist makes a mistake or becomes “errant” and enters the
median, there is a high probability that the motorist will cross the median and enter the
opposing direction of flow.
The long straight sections just prior the two noted horizontal curves with the downgrades
and differences in elevation between the two directions of flow also contribute to the
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likelihood of crossing the median in the two curved sections.
assigned for this factor.
A risk rating of ‘E’ was
Other than the median edge line, there is no other visible delineation of the median. The
rumble strip exists but the inside shoulders are only 1 to 3 feet in width. While the
pavement markings are in good condition and a rumble strip exists in the inside
shoulder, there is a relatively high number of median entries over this section (approx. 7
per year). Consequently, not having the median delineated was assigned a risk rating of
‘D’ while the narrow inside shoulder was assigned a ‘D’ given that there is some
relatively flat area immediately adjacent to the inside shoulder to help with recovery.
The high travel speeds along with the above noted physical conditions increases the risk
of median entries, it was assigned a ‘C’ rating. Sun glare and the low salt zone were
also noted as potentially contributing factors but likely having a smaller effect and were
assigned a ‘B’ rating.
Fatigue was also noted as a driver contributing cause and the long straight sections of
road may again potentially contribute to “lulling” the motorists, particularly if tired. A risk
rating of ‘D’ was assigned to this factor as a number of crashes cited fatigue as one
cause.
Once the potential issues had been identified and risk ratings assigned, suggested
actions intended to reduce the injuries and fatalities resulting from cross-median crashes
specifically and median related crashes in general were developed. Given that this RSA
is focused on cross-median events, the initial action evaluated was the potential
installation of a median barrier.
•
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 of 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 without a
barrier would be 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 I-95 section under study. While not
having a narrow median, the I-95 study section has a high volume, 5% trucks and a
history of cross-median crashes. 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 80
to 88 feet and a volume of over 80,000 vehicles on an average day, the intersection of
the two items would be off the chart where a barrier can be “optional”.
In addition to the chart and related warrant criteria, which is a guideline, further
consideration was given to the following:
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The high volume-high speed presents the potential for a greater number of
errant vehicles entering the median.
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Of the total median related crashes, a high proportion of cross-median (41%)
over the three (3) year period and the median appears to be crossable.
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Cross-over crashes have resulted in predominantly personal injuries or
fatalities.
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Fatigue and weather conditions also appear to have an effect (possibly in
combination with the dark, late night driving) in the median and cross-median
crashes.
Based on the evaluation and input from RSA team members, the likelihood of crossmedian events could be higher in the areas of the two horizontal curves following the
long tangent sections.
Consequently, based on the analysis of the data, the field drive-thru and discussion of
the conditions by the RSA team members, it has been concluded that a median barrier
be considered at a minimum, in the sections of this route that include the changes in
horizontal alignment and are currently open. These are the downgrade, curved sections
approaching Interchange No. 49 (southbound) and Interchange No. 51 (northbound).
The barrier would be included in tangent sections on both sides of the curve.
4
American Association of State Highway and Transportation Officials, Roadside Design Guide,
Washington, D.C., 2002, Chapter 6 Update 2006.
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median width
80-88 feet
80
AVERAGE DAILY TRAFFIC
(thousands)
70
BARRIER
RECOMMENDED
60
BARRIER
CONSIDERED
50
40
BARRIER
OPTIONAL
30
20
10
0
0
10
20
30
40
50
60
70
MEDIAN WIDTH
(feet)
Median Barrier Warrant Analysis
Interstate 95 Road Safety Audit
Danvers-Topsfield, Massachusetts
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NOT TO SCALE
Framingham, Massachusetts
Figure 10
I-95 Danvers-Topsfield Road Safety Audit
The approximate lengths of barrier in these two areas (Sections 1 and 3) would be in the
range of 1.1 to 1.2 miles. These areas are shown in Figure 11. Also shown in the figure
is the tangent section between the two curves at 1.1 mile in length. If all three sections
are covered by the barrier, it would total approximately 3.4 miles in length.
The remaining open area of the study section north of Interchange No. 51 could be
monitored and if cross-over crashes persist following the installation of barriers in the
two noted areas, then extending the barriers could be considered.
While the RSA team discussed the likely lower risks of crossing the median pertaining to
the more level, tangent highway sections, it is also recognized that the current method of
identifying crash locations is an approximation at best and that leaving gaps in areas of
similar risk may not adequately address the issue. At the same time, installing guardrail
along the entire study section would cost more then one million dollars. A cable barrier
has been shown to be less costly, however, the latest research indicates that anchored
sections of cable barriers should not exceed approximately one mile.
Consequently, there are installation options in terms of length and timeframe for the I-95
corridor. Final decisions can be made as funding availability and design details are
determined. The selection of the barrier is discussed in greater detail in the next section
followed by the complete set of I-95 RSA recommendations.
•
Barrier Selection
Once a decision is made to install a barrier, the type must be determined. There are a
number of barrier types that can be considered in addressing the median cross-over
crashes. Not all of these types are typically or currently used by MassHighway but they
are available and include the following:
♦
♦
♦
♦
Weak post W-Beam
Box Beam
Generic Low Tension Cable
High Tension Cable Barrier
♦ Strong post W-Beam
♦ Thrie Beam
♦ Concrete (Jersey)
In deciding on the type of barrier, there are a number of criteria suggested in the
AASHTO Roadside Design Guide5. These criteria used in selecting a barrier type are
included in Table 5.
5
American Association of State Highway and Transportation Officials, Roadside Design Guide,
Washington, D.C., 2002, Chapter 6 Update 2006.
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INT. NO. 51
OPTIONAL BARRIER AREA 2 APPROX. 1.1 MILES
PROPOSED BARRIER AREA 3 APPROX. 1.1 MILES
INT. NO. 50
PROPOSED BARRIER AREA 1 APPROX. 1.2 MILES
PROPOSED BARRIER LOCATION
Proposed Median Barrier Locations
Interstate 95 Road Safety Audit
Danvers-Topsfield, Massachusetts
MS Transportation Systems, Inc.
NOT TO SCALE
Framingham, Massachusetts
Figure 11
I-95 Danvers-Topsfield Road Safety Audit
Criteria
1. Performance Capability
2. Deflection
3. Site Conditions
TABLE 5
CRITERIA FOR BARRIER SELECTION
Comments
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.
4. Compatibility
Barrier must be compatible with planned end anchor and capable of
transitioning to other barrier systems (such as bridge railings).
5. Cost
Standard barrier systems are relatively consistent in cost, but highperformance railings can cost significantly more.
6. Maintenance
A. Routine
Few systems require a significant amount of routine maintenance.
B. Collision
Generally, flexible or semi-rigid systems require significantly more
maintenance after a collision than rigid or high-performance railings.
C. Material Storage
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.
D. Simplicity
7. Aesthetics
8. Field Experience
Source: AASHTO, Roadside Design Guide, 2002, Chapter 5 Roadside Barriers.
Based on extensive research and trials over the past five years, the high tension cable
barrier system has become more prominent in the U.S. The cable (flexible) barrier has
its advantages from a cost and aesthetic perspective 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.
In addition to the cable barrier systems, 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 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 somewhat similar though the thrie-beam has a higher cost. It’s been
noted that the thrie beam rail is typically used on the median side of the freeways in the
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Commonwealth where a barrier was determined necessary. The concrete barrier would
generally be applicable in urban sections with limited median widths available. As a
result of this review, it was determined that the median barrier options that are valid for
consideration for I-95 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
ƒ
Barrier hits per mile
Frequency of hits
Cost recovery
Cable downtime
Repair effect on traffic
Maintaining tension with cable system
Mowing median
Final selection of the barrier type should be based on the costs, physical condition of the
median, the ability to maintain a recovery zone, likely maintenance or repair
requirements, and compatibility with future planned pavement 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.
3 Cable CASS System on Route 213
MS Transportation Systems, Inc.
4 – Rope Brifen System on I-495
Page 20
I-95 Danvers-Topsfield Road Safety Audit
This barrier type can be installed on slopes of 6:1 or flatter with little constraint on
placement. There are certain systems (i.e. Brifen and Gibraltor 4 rope) that have been
approved for slopes as steep as 4:1. In addition to the lower installation costs, the cable
barrier can usually be located sufficiently away from the pavement area to allow for
recovery zone and a minimal number of hits.
Guardrail
The guardrail could be placed toward or in the center of the median where slopes are
10:1 or flatter (i.e. I-93 Braintree, Route 128 Needham) as well as at the edge of a steep
slope or where minimal recovery zones exist. With the guardrail placed within several
feet of the pavement edge, a clear zone (or recovery area) would be eliminated at least
on one side of the median if guardrail is applied on only one side of the median.
Per mile costs of the basic types of median barrier treatment to be considered for this
route are summarized in Table 6. Shown in the table are estimated per mile costs of
installing a cable barrier, a double faced W-beam guardrail and a double faced thriebeam guardrail. As can be seen, the cable barrier is expected to be the lower cost
option. It should be noted that the estimated costs for the cable barrier are largely based
on recent limited applications in the Commonwealth. Construction costs for cable
installation could be substantially lower based on experience in other parts of the country
(examples in Appendix). The W-beam rail is a lower cost option compared to the thriebeam, however, there is slightly greater deflection with the W-beam.
TABLE 6
COMPARISON PER MILE COSTS
Cable vs. Guardrail
Costs/Mile
Cable
W-beam
Thrie beam
$144,000
$171,000
$213,000
Based on the above costs, the installation of cable barrier in the three subsections
totaling 3.4 miles is estimated to cost approximately $490,000 while use of thrie-beam
would result in a cost of approximately $724,000.
The next section outlines all of the RSA team recommendations including the median
barrier.
MS Transportation Systems, Inc.
Page 21
I-95 Danvers-Topsfield Road Safety Audit
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 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 I-95 in Danvers-Topsfield.
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)).
TABLE 7
SUMMARY OF RECOMMENDATIONS
Risk Factor
Risk
Rating
Recommended
Action
ƒ
Estimated
Timeframe
$331,0001
ƒ
Medium to
long term
$490,0001
ƒ
Medium to
long term
Median is “open” throughout
project area except for
approaches to overpasses and
protection of some structures
E
Geometry of curves approaching
end of long tangent (long straight
section of highway north of Int. 49
(SB direction) and south of Int. 51
(NB direction) prior to curves.
E
Difference in elevation in areas of
curves – SB south of Int. 50 and
NB south of Int. 51 (relates to
curve geometry factor also)
E
ƒ Barrier would address in most
critical areas.
see above
Median is not delineated
D
ƒ Install reflective delineators
see above
High travel speeds exist on
section
C
ƒ Increase enforcement program
Inside shoulder is narrow
D
ƒ Widen to a minimum of 4’ paved
$2.2M
ƒ Long term as
part of overall
rehab project
Driver fatigue affected by long,
straight road section
D
ƒ Use VMS to provide effective
messages and break monotony
TBD
ƒ Use portable
VMS in short
term
Sun Glare – SB south of Int. 51 in
AM and NB north of Int. 50 in PM
B
ƒ Install standard caution signs (2)
$5,000
ƒ Short term
Some bridge columns
unprotected – at Route 1
overpasses
B
ƒ Install guardrail around columns of
Route 1 overpass
$16,000
ƒ Short term
Low salt area - not signed
B
ƒ Install new signs (assume 6 total)
$3,000
ƒ Short term
1
ƒ
Install median barrier in higher risk
sections – 2.3 miles (see Figure 11)
Install median barrier along section
from Int. No. 49 thru Int. No. 51 (3.4
miles)
Estimated
Cost
ƒ Install reflective delineators
ƒ Install curve warning signs or
chevron signs on curve
$7,000
ƒ Short to
medium term
$5,000
ƒ Short term
TBD
See above
ƒ Short to
medium term
ƒ Short term
Assumes cable barrier
MS Transportation Systems, Inc.
Page 22
I-95 Danvers-Topsfield Road Safety Audit
The I-95 study section has an open median and although it is between 80 to 88 feet
wide, there is a high proportion of cross-over crashes. It is recommended that a median
barrier be installed in the two most noted areas of concern by the RSA team – those
being in the areas of the curves south of Interchange 50 and south of Interchange 51. If
cable barrier is installed covering these two higher risk areas as well as the tangent
section in between, it is estimated to have a construction cost of approximately
$490,000. The designer will need to verify the grades of the median prior to specifying
the type and location of cable.
In addition to the open median, the design of the study section includes two (2) large
radius horizontal curves that exist at the ends of the long tangent section (southbound at
Interchange No. 49 and northbound at Interchange No. 51) coupled with the downgrades
and directional differences in elevation can contribute to the occurrence of cross-median
crashes. Altering the geometry is clearly not feasible, but the installation of the barrier
noted above would alleviate this potential risk.
It is also recommended that the median be delineated along both sides with flexible,
reflective posts. This short term action is estimated to cost $7,000. Also in the short
terms, either curve warning signs or chevron signs could be put in place on the two
curves noted in the above paragraph.
A factor discussed by the RSA team is that having long, straight sections of highway
may contribute to driver fatigue or inattention. An action that could be considered to help
address this factor is the use of variable message signs (VMS) that could display a
variety of messages to inform motorists of operating conditions and other items to
enhance driver behavior. The typical flashing of the message may also have a positive
effect on driver attention. The VMS system could initially consist of a series of portable
sign boards. There is a portable VMS currently located in the vicinity of Interchange No.
52. In the long term, permanent installations as part of a cohesive ITS-VMS plan can be
implemented. The costs of the portable VMS boards are estimated at approximately $30
per day, not including the communication costs.
The widening of the inside shoulder if installed by itself is a major, high cost ($2.2M)
action that while desirable, is best addressed as part of an overall surface rehabilitation
project. However, as part of an overall rehab project, the incremental cost to widen the
shoulder will be significantly lower.
The “sun glare” and “low salt zone” factors can be addressed through signage. Figure
12 illustrates an example of a sign that could be used for these factors.
MS Transportation Systems, Inc.
Page 23
CAUTION
LOW SALT ZONE
USE CAUTION
SOLAR GLARE
IN AM
(Alt. - IN PM)
CONCEPTUAL ONLY NOT TO SCALE
Potential Sign Legends
I-95 Road Safety Audit
Danvers-Topsfield, Massachusetts
MS Transportation Systems, Inc.
Framingham, Massachusetts
Figure 12
I-95 Danvers-Topsfield Road Safety Audit
The high speeds are a factor that can be further addressed through increased,
consistent enforcement, but this requires additional personnel. The RSA team
recommends additional budget for increased police presence.
Lastly, the RSA noted that there are unprotected bridge columns (Route 1 overpasses)
in the study section. While not a factor of risk to cross-median crashes, the conditions
increases the potential severity of a fix object crash as well as possible damage to the
columns. Consequently, it is recommended that guardrail be placed in these areas in
the short term.
MS Transportation Systems, Inc.
Page 25
I-95 Danvers-Topsfield Road Safety Audit
Appendix
•
•
•
•
•
MS Transportation Systems, Inc.
RSA Meeting Agenda
RSA Attendees List
Median Crash Diagram
Crash Data
Traffic Volume Data
Page 26
Road Safety Audit
Danvers/Topsfield/Boxford – I-95
Meeting Location: MassHighway District 4 Office
519 Appleton Street, Arlington
Thursday, July 31, 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 the Day – but the RSA has not ended
Instructions for Participants:
• Before attending the RSA on July 31st participants are encouraged to drive
Interstate 95 between interchanges 48 and 53 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
I-95 Danvers-Topsfield July 31, 2008
MassHighway District 4 Offices, Arlington MA
Attendance List
Name
Agency/Dept.
Email
Bill Scully
MS Transportation Systems, Inc.
bscullyjr@mac.com
Lyris Liautaud
MHD Highway Design
Lyris.Liautaud@state.ma.us
Bonnie Polin
MHD Safety
Bonnie.Polin@state.ma.us
Kaiyan Jiang
MHD Highway Design
Kaiyan.Jiang@mhd.state.ma.us
Efi Pag___________
Boston Region MPO
EfiP@CTPS.org
Andrew Hirshfield
MHD Traffic
Andrew.Hirshfield@mhd.state.ma.us
Lisa Schletzbaum
MassHighway Safety
Lisa.Schletzbaum@mhd.state.ma.us
Tim White
Federal Highway Admin.
Timothy.A.White@fhwa.dot.gov
Paul Fletcher
Mass State Police "A"
Paul.Fletcher@state.ma.us
Brett Loosian
MHD, District 4, Maintenance
Brett.Loosian@mhd.state.ma.us
John Gregg
MHD, District 4, Traffic
John.Gregg@mhd.state.ma.us
MS Transportation Systems, Inc.
IPSW
±
Interstate 95 Median Crashes
ICH
ROA
D
TR
OA
D
DS
HR
1
PO
N
W IC
EE
T
53
"
)
IP S
MAI
N
ST R
EE T
IPSWICH
ER H
IPS
IL L
R
CH
WI
D
OA
R OA
NORTH ANDOVER
HAV
52
"
)
BOXFORD
Crash IDs
between 2-4
D
SA
5
TO
WASHING
LE
6
N STREET
M
ST
RE
7
ET
RO W LE
95
EE
TR
VA
L
RNP
20
D
OA
YR
LE
VA
L
LOCUST STREET
ET
RE
ST
AD
21
RE
ST
ET
PINE STREET
ST
"
)
47
ET
48
"
)
RE
LS
TR
EE
T
Local
RE
CABOT RO
22
ST
RIVER STREET
RE
AM
EET
E
PL
ST
EY
RL
R EE T
18
FO
BO S T
O N ST
ST R
MA
Collector
* 2007 crash file has not Ryet
been closed.
U
Miles
1
WENHAM
BU
Minor Arterial
49
"
)
REET
Median, Non-Fatal Crash
0.75
AD
NH
ST
DAYTON
Principal Arterial
SS
EL
N OR
TH
19
Cross Median, Non-Fatal Crash
0.5
NEW
DANVERS
Interstate
EE T
16
17
Cross Median, Fatal Crash
Municipal Boundary
0.25
"
)
EET
Major Roads
NORTH READING
0
E ST R
50
SUMMER STREET
Type of Median Crash 2004-2007 *
S TR
O
WE
EA
S
M APL
Legend
EL M
R
TS
EET
14
TR
ET
EE
RE
STR
15
T
ST
EST
BU R
YPO
RT
TU
TY
ER
MIDDLETON
F OR
IKE
S TR
ST
S
EA
DY
LIB
ET
PE
O
AB
Y
AD
RE
ST
TR
13
RO
EX
LS
M
S
ES
SC
O
HO
T
EE
T
EE
TR
LE
LE
EE
SA
12
T
E R OA D
Crash IDs
between 8-11
HS
Y BRIDG
51
"
)
T
TOPSFIELD
HIG
§
¨
¦
T EN
HO L
ST R
EET
ET
MASSACHUSETTS HIGHWAY SAFETY DIVISION
CRASH SUMMARY
ROADWAY:
NO.
CITY:
DANVERS, TOPSFIELD AND BOXFORD
LOCATION:
EXIT 50 - 51
I-95
STUDY PERIOD:
CRASH NUMBER
1/1/2004
TO
CRASH DAY
12/31/2007
TIME OF DAY
CRASH DATE
TRAVEL
LIGHT
WEATHER
ROAD
REASON FOR
VEHICLE
TYPE OF
DRIVER CONTRIBUTING
CRASH
DIRECTION
CONDITION
CONDITION
SURFACE
RUNNING OFF ROAD LEFT
MOVEMENT
MEDIAN CRASHES
CAUSE
SEVERITY
1
2052170
Monday
2:45 PM
12/26/05
NB
Daylight
Clear
Dry
Unknown vehicle struck another vehicle in the rear, caused the vehicle to cross the median and hit another vehicle
S/B Travel Lane to N/B Travel Lane
Cross Median
Followed too closely
2
2130034
Sunday
12:00 PM
08/20/06
SB
Daylight
Cloudy
Wet
Unknown vehicle caused another vehicle to take evasive action and hit the guardrail
Travel Lane to Median Guardrail
Median
Failure to keep in proper lane
Property Damage Only
3
2021845
Sunday
12:45 PM
09/18/05
SB
Daylight
Cloudy
Dry
Vehicle tire blew out and lost control of vehicle
Travel Lane to Median
Median
No Improper Driving
Non-Fatal Injury
Non-Fatal Injury
4
1984400
Friday
8:00 PM
01/28/05
SB
Dark - Not Lighted
Clear
Wet
Vehicle drifted into median and overturned
Travel Lane to Median
Median
Failure to keep in proper lane
Property Damage Only
5
2112454
Tuesday
6:12 AM
05/09/06
SB
Daylight
Clear
Dry
Driver suffered a coronary heart failure, vehicle struck a tree and caught on fire
S/B Breakdown Lane to N/B Breakdown Lane
Cross Median
History Heart/Epilepsy/Fainting
Non-Fatal Injury
6
2059780
Thursday
3:40 PM
06/22/06
NB
Daylight
Cloudy
Dry
Vehicle was cut-off by unknown vehicle and hit the guardrail
Travel Lane to Median
Median
Failure to keep in proper lane
Property Damage Only
7
2050306
Monday
1:02 AM
04/17/06
SB
Dark - Not Lighted
Clear
Dry
Travel Lane to Median to Travel Lane to Median
Median
Failure to keep in proper lane
Non-Fatal Injury
N/B Travel Lane to S/B Right Rock Embankment
Cross Median
Failure to keep in proper lane
Non-Fatal Injury
N/B Travel Lane to Median to Travel Lane to S/B Right Tree Line
Cross Median
Exceeded Speed Limit
Non-Fatal Injury
8
2225650
Friday
6:05 PM
08/03/07
NB
Daylight
Clear
Dry
Vehicle drifted to the left, the tires left the paved surface, lost control of vehicle and overturned
Vehicle changed lanes to an already occupied lane, to avoid collision swerved to the left, hit another vehicle and
crossed the median
9
2258069
Wednesday
6:05 PM
07/11/07
NB
Daylight
Not Reported
Dry
Driver was operating in erratic manner, collided with another vehicle, crossed the median and overturned
10
2093941
Saturday
10:35 AM
08/26/06
SB
Daylight
Clear
Dry
Driver was operating in aggressive manner, hit another vehicle, started to spin out and it was struck by another vehicle Travel Lane to Median
Median
Operating vehicle in reckless manner
Property Damage Only
11
2114665
Wednesday
7:01 AM
05/10/06
SB
Daylight
Rain
Wet
Vehicle hydroplaned, crossed the median and struck another vehicle
N/B Travel Lane to S/B Travel Lane
Cross Median
Swerving due to slippery surface in roadway
Property Damage Only
12
1915873
Monday
7:56 AM
03/14/05
NB
Daylight
Clear
Dry
Travel Lane to Median
Median
Exceeded Speed Limit
Non-Fatal Injury
N/B Travel Lane to Median Guardrail to Travel Lane to S/B Travel Lane
Cross Median
Operating vehicle in reckless manner
Fatal Injury
Travel Lane to Far Median
Median
Distracted
Non-Fatal Injury
Non-Fatal Injury
13
1919756
Sunday
11:10 PM
05/15/05
NB
Dark - Not Lighted
Cloudy
Dry
Driver had a sneezing sequence, hit a patch of ice and struck a police car
Vehicle went left, struck the guardrail, sideswiped another vehicle, crossed the median and crashed head-on with a
tractor trailer
14
2054550
Sunday
6:15 PM
06/04/06
NB
Daylight
Clear
Dry
Driver was startled by a spider, lost control and overturned
15
1769465
Saturday
1:25 AM
07/24/04
SB
Dark - Not Lighted
Clear
Dry
Fallen asleep, vehicle sideswiped another vehicle and overturned
Travel Lane to Median
Median
Fatigued/Asleep
16
2014951
Sunday
1:40 PM
03/05/06
SB
Daylight
Clear
Dry
Fallen asleep and vehicle overturned
Travel Lane to Median Guardrail to Overpass
Median
Fatigued/Asleep
Non-Fatal Injury
17
2014962
Saturday
5:26 PM
02/25/06
SB
Dusk
Snow
Snow
Driver felt the rear wheel loose traction, lost control of vehicle and crossed the median
S/B Travel Lane to N/B Right Guardrail
Cross Median
No Improper Driving
Non-Fatal Injury
18
2060614
Tuesday
3:00 AM
07/04/06
NB
Dark - Not Lighted
Clear
Dry
Fallen asleep and vehicle overturned
Travel Lane to Median to Median Guardrail
Median
Fatigued/Asleep
Non-Fatal Injury
19
2059740
Tuesday
1:25 AM
06/06/06
NB
Dark - Not Lighted
Clear
Dry
Fallen asleep and vehicle overturned
Travel Lane to Median Guardrail to Median
Median
Fatigued/Asleep
Non-Fatal Injury
Property Damage Only
20
1919253
Monday
12:20 PM
06/20/05
SB
Daylight
Clear
Dry
Lost control of vehicle and sideswiped a tractor
Travel Lane to Median
Median
Failure to keep in proper lane
21
2281303
Wednesday
6:00 AM
02/14/07
NB
Daylight
Snow
Snow
Lost control of vehicle, crossed the median and was struck by another vehicle
N/B Travel Lane to S/B Travel Lane
Cross Median
Failure to keep in proper lane
Non-Fatal Injury
22
2061113
Thursday
4:55 PM
05/18/06
SB
Daylight
Clear
Dry
Vehicle sideswiped another vehicle, crossed the median, overturned and impacted another vehicle while airborne
S/B Travel Lane to N/B Right Breakdown Lane
Cross Median
Exceeded Speed Limit & Drugs
Non-Fatal Injury
23
1854184
Monday
6:00 AM
12/20/04
SB
Dark - Not Lighted
Cloudy
Wet
Lost control of vehicle, crossed the median and hit another vehicle
S/B Travel Lane to N/B Travel Lane
Cross Median
Failure to keep in proper lane
Property Damage Only
24
1999995
Saturday
11:35 AM
10/15/05
SB
Daylight
Rain
Wet
Lost control of vehicle due to heavy rain and overturned
S/B Travel Lane to N/B Travel Lane
Cross Median
Driving too fast for condition
Non-Fatal Injury
25
2040692
Tuesday
5:20 AM
03/29/05
SB
Dark - Not Lighted
Rain
Wet
Median
Failure to keep in proper lane
Non-Fatal Injury
26
2189809
Friday
Not Reported
05/04/07
NB
Daylight
Clear
Dry
Vehicle abruptly changed lane and struck the right corner of another vehicle
Travel Lane to Median
Driver was operating in aggressive manner, hit another vehicle, swerved to the median, entered traffic again and had a
further crash
Travel Lane to Median to Travel Lane
27
2242408
Thursday
2:05 PM
03/22/07
SB
Daylight
Clear
Dry
Fallen asleep, hit another vehicle and caused the vehicle to enter the median
LIGHT CONDITION
WEATHER CONDITION
ROAD SURFACE
TOTAL NO.
DAYLIGHT
DUSK
DARK - NOT LIGHTED
CLEAR
CLOUDY
RAIN
SNOW
NOT REPORTED
DRY
27
18
1
8
16
5
3
2
1
19
6
100%
67%
4%
30%
59%
19%
11%
7%
4%
70%
22%
ROAD SURFACE
SNOW
MEDIAN OR CROSS MEDIAN
MEDIAN
CROSS MEDIAN
CRASH SEVERITY
PROPERTY DAMAGE
WET
DRIVER CONTRIBUTING CAUSE
NO IMPROPER
NON-FATAL INJURY FATAL - INJURY
DRIVING
ONLY
EXCEEDED SPEED
LIMIT
EXCEEDED SPEED
LIMIT & DRUGS
FOLLOWED TOO
DRIVING TO FAST FOR CONDITION
CLOSELY
2
16
11
8
18
1
2
2
1
1
1
7%
59%
41%
30%
67%
4%
7%
7%
4%
4%
4%
FAILURE TO
KEEP IN
PROPER LANE
OPERATING
VEHICLE IN
RECKLESS
MANNER
DISTRACTED
FATIGUED/
ASLEEP
DRIVER CONTRIBUTING CAUSE
SWERVING DUE TO
SLIPPERY SURFACE
IN ROADWAY
HISTORY
HEART/EPILEPSY/
FAINTING
9
3
1
1
1
5
33%
11%
4%
4%
4%
19%
2007 CRASH RECORDS ARE NOT COMPLETE
CRASH SUMMARY IS BASED ON CRASH REPORTS WITH STATE POLICE NARRATIVES
Median
Travel Lane to Median to Travel Lane to Median to First Bridge Support CaisMedian
Operating vehicle in reckless manner
Non-Fatal Injury
Fatigued/Asleep
Property Damage Only
I-95, North of Rt 1 04/26/2007
Northbound Southbound
Direction
Direction
Start time
12:00 AM
321
169
1:00 AM
152
115
2:00 AM
126
114
3:00 AM
109
177
4:00 AM
168
482
5:00 AM
477
1,799
6:00 AM
1,104
4,486
7:00 AM
1,875
5,295
8:00 AM
1,773
4,244
9:00 AM
1,564
2,964
10:00 AM
1,580
2,248
11:00 AM
1,826
2,059
12:00 PM
1,953
1,897
1:00 PM
2,186
1,848
2:00 PM
3,025
2,059
3:00 PM
3,895
2,319
4:00 PM
4,493
2,138
5:00 PM
4,818
2,212
6:00 PM
3,707
1,782
7:00 PM
2,631
1,172
8:00 PM
1,802
909
9:00 PM
1,427
712
10:00 PM
1,051
529
11:00 PM
644
314
Daily Total
42,707
TOTAL
490
267
240
286
650
2,276
5,590
7,170
6,017
4,528
3,828
3,885
3,850
4,034
5,084
6,214
6,631
7,030
5,489
3,803
2,711
2,139
1,580
958
42,043
84,750
Northbound Direction
Southbound Direction
5,000
4,500
4,000
3,500
3,000
2,500
2,000
1,500
1,000
500
Time of Day
PM
:0
0
PM
10
00
PM
8:
00
PM
6:
00
4:
00
PM
PM
2:
:0
0
AM
12
:0
0
AM
10
00
AM
8:
6:
00
AM
4:
00
AM
00
2:
:0
0
AM
0
12
Hourly Volume (Number of Vehicles)
Directional Traffic Volumes along I-95, North of RT 1, Topsfield
Thursday, April, 26, 2007
I-95, North of RT-62 (Maple Street) 04/26/2007
Northbound Southbound
Direction
Direction
TOTAL
Start time
12:00 AM
330
161
491
1:00 AM
162
99
261
2:00 AM
120
110
230
3:00 AM
112
180
292
4:00 AM
176
460
636
5:00 AM
489
1,807
2,296
6:00 AM
1,163
4,346
5,509
7:00 AM
1,912
4,557
6,469
8:00 AM
1,843
3,641
5,484
9:00 AM
1,589
2,567
4,156
10:00 AM
1,598
2,014
3,612
11:00 AM
1,775
1,830
3,605
12:00 PM
1,949
1,649
3,598
1:00 PM
2,143
1,712
3,855
2:00 PM
2,757
1,812
4,569
3:00 PM
3,667
1,902
5,569
4:00 PM
4,244
1,867
6,111
5:00 PM
4,500
1,900
6,400
6:00 PM
3,602
1,559
5,161
7:00 PM
2,482
1,035
3,517
8:00 PM
1,703
803
2,506
9:00 PM
1,357
650
2,007
10:00 PM
1,044
464
1,508
11:00 PM
668
281
949
Daily Total
41,385
37,406
78,791
Northbound Direction
Southbound Direction
5,000
4,500
4,000
3,500
3,000
2,500
2,000
1,500
1,000
500
Time of Day
PM
0
PM
:0
10
00
PM
8:
00
PM
6:
00
4:
00
2:
0
:0
12
PM
PM
AM
0
AM
:0
10
00
AM
8:
00
AM
6:
00
AM
4:
00
2:
:0
0
AM
0
12
Hourly Volume (Number of Vehicles)
Directional Traffic Volumes along I-95, North of RT 62, Danvers
Thursday, April, 26, 2007