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Safety and Traffic Engineering
MEMORANDUM
TO:
Eamon Kernan, Project Manager
FROM:
Corey O’Connor, Traffic Engineer
DATE:
July 10, 2015
RE:
Project 606574: Andover, RSA at Route 28 and I-495 NB ramps
The purpose of this Memorandum is to summarize the Road Safety Audit (RSA) that was held for the interchange
of Interstate 495 northbound and Route 28 in the Town of Andover, MA. The intent of the RSA was to have an
open ended discussion with attendees to highlight safety issues at the said location and develop possible
mitigation measures, or countermeasures, to address the safety issues. Countermeasures should be incorporated
in the short term by MassDOT District staff or in some future project. The RSA was held on June 24, 2015 in the
Andover Public Safety Complex and a list of members who attended this RSA is below in Table 1.
Table 1. Andover, I-495 and Route 28 RSA Attendees.
Lisa Schwarz – Town of Andover Planning
Buu Tran – MassDOT, Boston, Traffic
Charles Edgerly – Town of Andover Police and Safety
Corey O’Connor – MassDOT, Boston, Traffic
Pat Keefe – Town of Andover Police Chief
Adam Prichard – MassDOT, Boston, Intern
John Gregg – MassDOT, D4, Traffic Operations
Michelle Deng – MassDOT, Boston, Intern
Keith Arnold – MassDOT, D4, Projects
Shardly Romelus – MassDOT, Boston, Intern
Eamon Kernan – MassDOT, Boston, Highway Design (Project Manager)
The entire interchange of 495 and Route 28 is included in an Interstate 495 resurfacing project that is currently in
design by District 4 staff (MassDOT Project 606574), referred to as “the resurfacing project” hereafter. The
resurfacing project will begin in the Town of Andover just north of Exit 39 on I-495 and continue just north of Exit
43 in North Andover. Most on- and off-ramps will be included into the resurfacing project along with some of the
secondary state highways immediately adjacent to the ramps, including the entire interchange of I-495 and Route
28. As Project 606574 is only a resurfacing project, all work being done will be within the existing highway crosssections.
It is understood that all countermeasures to safety issues discussed at the RSA should be incorporated into the
resurfacing project as long as the countermeasures are easily achievable within the current project’s scope.
Countermeasures that fall too far outside of the resurfacing project’s scope may be considered in a future project.
There is also an ongoing guide sign replacement contract within the area of the interchange of I-495 and Route 28
therefore any guide sign recommendations resulting from the RSA may be implemented through the ongoing
contract.
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Crash Data Background
Crash data based from local and state police reports were collected for the entire I-495 and Route 28 interchange
from 2011 to 2013. A very large majority of the crashes collected occurred in the southern portion of the
interchange at the intersections of the I-495 NB ramps and Route 28 therefore discussion was mostly focused only
on this portion of the interchange. From the collected reports, 33 crashes were found at the intersection of the I495NB ramps and Route 28. 11 of the 33 crashes resulted in injury and none resulted in any fatalities. An
Equivalent Property Damage Only (EPDO) rating was calculated and found to have a rating of 77 which classifies
the area of the I-495 NB ramps and Route 28 as a high crash location within the Merrimack Valley Planning
Commission’s area. The detailed crash diagram and crash summaries can be found in the appendix of this
document.
Summary of Safety Issues and Possible Countermeasures
1. Interchange Geometry and Control
In the vicinity of the interchange, Route 28 is a four lane divided secondary highway (two lanes in each
direction) with a wide grass median. I-495 is a six lane Interstate (three lanes in each direction). The
interchange between I-495 and Route 28 offers full access from and to every direction (eight maneuvers total).
The geometry of the entire I-495 and Route 28 interchange is unique in that it has characteristics of a
cloverleaf, diamond and fly-over interchange design.
During the RSA two particular maneuvers within the interchange were understood to have been contributing
to many of the crashes at the interchange: the I-495 south to Route 28 north maneuver and the Route 28
south to I-495 north maneuver. Vehicles on I-495 south wishing to go Route 28 north must get off of the Exit
41 loop ramp and merge onto Route 28 south. These vehicles must then weave to the left lane of Route 28
south within 700 feet and make a U-turn in the small roadway segment provided in the median connecting
Route 28 north and south, referred to as “the U-turn segment” hereafter. Vehicles on Route 28 south wishing
to go I-495 north must also use the U-turn segment however instead of making a complete U-turn onto Route
28 north they must cross two lanes of Route 28 north traffic onto the I-495 north on-ramp. The U-turn
segment is under stop control while vehicles on Route 28 north have the right of way and flow freely. There is
a single post mounted flashing red beacon provided for vehicles at the stop controlled U-turn segment and a
four section post mounted flashing yellow “wig-wag” beacon for vehicles approaching on Route 28 north.
The U-turn segment described above is a host to the majority of the 33 crashes analyzed at this location. The
predominant crash type is angle collisions between a Route 28 northbound vehicle and a vehicle exiting the Uturn. 12 of the 33 crashes are of this manner and four of which resulted in injury. These angle crashes may
occur due to the fact that two major interchange movements must utilize this U-turn segment which creates a
large demand for the U-turn segment. With close to 15,000 vehicles per day traveling on Route 28 north,
finding a gap in two lanes of conflicting traffic may be difficult as well. With such demand for the U-turn
segment and large conflicting volume on Route 28 north, queues form at the stop line on the U-turn segment
and spill back onto Route 28 south during the A.M. and P.M. peaks. Frustration and pressure from other
vehicles in the queue may build for drivers in the queue which may lead the drivers at the stop line to accept
an unsafe gap in traffic which may cause an angle crash. A few close calls between vehicles departing the
stop line on the U-turn segment and Route 28 north were observed during the audit.
As described above, the U-turn segment handles two movements: vehicles turning left onto Route 28 north
and vehicles traveling straight to access I-495 north. It was observed during the audit that vehicles will stack
side by side at the stop line on the U-turn segment. When this occurs, the vehicle waiting to travel straight
onto I-495 north will block the view of the Route 28 north traffic from a vehicle waiting to turn left at the stop
line on the U-turn segment. This may cause a vehicle waiting to turn left to inadvertently pull out into Route
28 north at an inappropriate time causing an angle crash.
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Another contributing factor for angle collisions related to the geometry may be the separate but adjacent Uturn segment for Route 28 north to access Route 28 south. This north to south U-turn segment is located just
south of the U-turn segment for south to north/I-495 north. Vehicles on Route 28 north accessing the U-turn
segment to access Route 28 south may slow down in the inside lane and, especially if it is a large vehicle, block
the view of a through vehicle in the outside lane from vehicles queuing at the stop line at the U-turn segment
for south to north/I-495 north. A vehicle at the stop line on the south to north/I-495 north U-turn segment
may incorrectly assume that it is safe to enter or cross Route 28 north and cause an angle crash.
Rear-end crashes may also be contributed to the U-turn segment for south to north/I-495 north. The cross
section of Route 28 south consists of two lanes throughout the interchange; however, for approximately 300
feet, Route 28 south widens prior to the U-turn segment to accommodate a non-marked de facto
storage/deceleration lane for the U-turn segment. Due to poor pavement conditions, vehicles will often avoid
this de facto storage/deceleration lane therefore slow down and queue in the inside through lane of Route 28
south. To exacerbate the issue, it was mentioned that the queue from the U-turn segment may spill back to
the I-495 south off ramp located about 700 feet upstream from the U-turn segment. Vehicles on I-495 south
wishing to access Route 28 north must then find a way to enter the queue and often will often block one or
more lanes of Route 28 south through traffic while doing so. This queue spill back and vehicles decelerating
may have contributed to the five rear-end crashes on Route 28 south in the vicinity north of the U-turn
segment.
Another geometrical feature that causes safety issues is the the proximity of the I-495 northbound/Route 28
southbound ramp to the U-turn segment. The I-495 north/Route 28 south ramp is located about 100 feet
upstream from the U-turn segment. It was observed that vehicles will use the I-495 north/Route 28 south
ramp and try to weave across Route 28 south to try to access the U-turn segment. This maneuver may have
contributed to the two side-swipe/angle crashes between a vehicle on the off-ramp and a through vehicle on
Route 28 south. This maneuver may also contribute to rear-end crashes as vehicles are focusing on weaving
across Route 28 and not the queue that may have formed from the U-turn segment. Vehicles on the I-495
north/Route 28 south ramp should have no reason to access the U-turn segment because there is a separate
loop ramp for I-495 north to Route 28 north. This move is also strongly discouraged by ways of a “NO TURNS”
sign and a solid white lane line along the 100 foot weave section of roadway in between the I-495 north offramp and the U-turn segment.
The geometry of the merge area from the I-495 north/Route 28 south ramp may have also contributed to
other crashes not related to the U-turn segment. The ramp from I-495 north intersects Route 28 south at a
very skewed angle such that vehicles merging onto Route 28 south from the ramp may feel that they may not
have to yield to Route 28 south traffic despite the presence of yield signs. This scenario may have been the
cause of the two side-swipe/angle crashes recorded at this location. Furthermore, drivers who do yield at the
bottom of the ramp must look almost 180 degrees backwards to see the conflicting traffic on Route 28 south.
This scenario may have contributed to some of the rear-end crashes in the area as drivers take their eyes off of
the vehicle in front of them to look backwards towards the conflicting traffic.
The geometry of the I-495 north/Route 28 south ramp may also contribute to the two single vehicle crashes
near the end of the ramp in which the vehicles lost control and slid into the grassy gore area at the curve prior
to the merge point. The downward grade of the ramp combined with the sharp corner prior to the merge
point is most likely a factor into these two single vehicle crashes.
Potential Enhancements:
Reconstruct the interchange. Although this recommendation is a long term, high cost
enhancement, well beyond the scope of the resurfacing project, reconstructing the
interchange and eliminating the U-turn segment (by constructing a single point urban
interchange (SPUI) or by providing separate ramps for I-495 south to 28 north and Route 28
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south to I-495 north) are the most effective ways to eliminate most of the crashes at this
location. Once the conflict between the U-turn segment and Route 28 north is eliminated all
of the angle crashes at this location will be eliminated and rear-end crashes on Route 28
south will be mitigated by the removal of the queue spill back.
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Signalize the U-turn segment and Route 28 north. Signalizing the U-turn segment and
Route 28 is a long term, high cost enhancement that is outside of the scope of the
resurfacing project. By signalizing these two approaches many of the angle crashes may be
reduced between the U-turn segment and Route 28 north. This will remove the
responsibility of the driver to determine whether a gap is acceptable or not. Also, as long as
the signal processes traffic well, the queue spill back onto Route 28 south may be relieved
hence reducing the rear-end crashes. Even though this enhancement is outside of the scope
of this project, it is recommended that this enhancement is considered for a future project.
Minor geometrical changes may also be required in order to make this enhancement most
effective.
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Mount flashing beacons overhead. Although mounting flashing beacons overhead may not
be as effective in reducing crashes as the previous two safety enhancements, it may make
the intersection more conspicuous and make more drivers more alert. This may mitigate the
angle crashes between the U-turn segment and Route 28 north. Mounting beacons
overhead is a high-cost, mid-term enhancement and is outside the scope of the resurfacing
project.
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Reduce Route 28 north to one lane at the U-turn segment. Reducing Route 28 north to one
lane at the U-turn segment may reduce angle crashes due to the fact that vehicles departing
the U-turn segment will only have to cross one lane of traffic. Reducing Route 28 north to
one lane in this area may also calm traffic and reduce speeds. This enhancement may be
accomplished by making the outside lane on Route 28 north exit only to the I-495 north on
ramp. The second lane may then be re-added downstream of the U-turn segment; either by
creating an add-a-lane for vehicles using the U-turn segment to access Route 28 north or by
creating an add-a-lane for vehicles entering Route 28 north from the I-495 north off-ramp.
This enhancement can be accomplished with pavement markings only therefore is a shortterm and low-cost enhancement that may be considered as part of the resurfacing project.
The operational effects of Route 28 north shall be analyzed to determine if the elimination
of a through lane will create other issues if this enhancement is considered.
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Define lanes on the U-turn segment. It should be determined whether the U-turn segment
should provide one lane for lefts and throughs to share or two lanes, one for each. Providing
two lanes will provide more storage for vehicles queued at the stop line however the issue of
the through vehicle blocking the view of the left turning vehicle will still exist at the stop line.
Furthermore, if two lanes are provided, two lanes will most likely spill back into Route 28
south and may cause additional safety concerns. Providing one lane at the U-turn segment
will eliminate the issue of a through vehicle blocking the view of a left turning vehicle and
the spill back from one lane may be accommodated more safely given the current crosssection restrictions. This may reduce the number of angle crashes. Defining lanes on the U-
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turn segment is a short-term and low-cost enhancement that can be done within the scope
of the resurfacing project through striping.
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Provide a formal storage/deceleration lane on Route 28 south for the U-turn segment. By
providing a separate lane for storage and deceleration for vehicles accessing the U-turn
segment rear-end crashes may be reduced by removing these queued vehicles from the
through lanes and by providing a safe area to decelerate outside of the through lanes. This
enhancement may be done with pavement markings provided that the cross section is wide
enough. If so, this enhancement is a short-term and low-cost enhancement and should be
done as part of the resurfacing project. Widening of the cross section may be needed to
make this enhancement most effective. Widening of the cross section is a high-cost and
long-term recommendation outside the scope of this project.
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Provide a solid double white lane line on Route 28 south in the area of the I-495 north offramp. According to the MUTCD, crossing a solid double white line is prohibited. In attempt
to further discourage vehicles from accessing the U-turn segment from the I-495
north/Route 28 south ramp a solid double white lane line can be applied on Route 28 south
in the vicinity of the ramp. A R4-9 (STAY IN LANE) sign may also be provided to reinforce the
solid double white line. Although all vehicles may not adhere to this treatment, these
enhancements may reduce the amount of side-swipes and rear-end crashes in the area of
the U-turn segment. Both the solid double white line and R4-9 sign are low-cost and shortterm enhancements that can be done within the scope of the project.
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Extend the gore of the I-495 north/Route 28 south off-ramp downstream past the U-turn
segment. Extending the gore of the I-495 north/Route 28 south off-ramp downstream past
the U-turn segment by means of textured pavement and/or pavement markings will further
discourage vehicles exiting the I-495 off-ramp from crossing Route 28 south to access the Uturn segment hence reducing the related crashes. This enhancement may require minor
widening of Route 28 south therefore is a high-cost and long-term enhancement that may
be outside of the scope of the resurfacing project.
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Provide a smaller radius of entry on the I-495 north/Route 28 south off-ramp. Having the I495 north off-ramp intersect Route 28 south at a smaller radius, say 30 degrees, will allow
drivers to easily view oncoming traffic on Route 28 south at the yield line on the off-ramp.
This will eliminate the need for drivers look over their shoulder hence reducing the amount
of rear-ends in the area. Additionally, with a lesser angle of entry, drivers will be required to
come to more of a stop at the yield line hence increasing the conformance at the yield line
and reducing the side-swipe/angle crashes caused by vehicles failing to yield. Finally, this
enhancement may also reduce the amount of single vehicle crashes at the end of the offramp as the sharp curve to align the off-ramp parallel with Route 28 south will be
eliminated. This is a long-term and high-cost enhancement that is outside of the scope of
the resurfacing project. This enhancement may also be considered for all ramps throughout
the interchange.
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2. High Speeds
High speeds on Route 28 within the area of the I-495 interchange were noted to possibly contribute to crashes.
Route 28 has a regulated speed of 35 mph within the area of the interchange however speeds seemed to be
higher from observations during the RSA, especially on Route 28 north. To confirm these field observations
Andover police set up traffic data recorders on Route 28 north and south to record volumes and speeds. These
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traffic data recorders confirmed the field observations: the 85 percentile speeds on Route 28 north and south
were 42 and 37 mph, respectively. The traffic data recorders also found that it is not rare that vehicles travel at
speeds greater than 50 mph and even 70 mph. The full data set from these traffic data recorders can be seen
at the end of this document in the Appendix.
High speeds can contribute to all crash types. Angle crashes were specifically called out as a consequence of
high speeds because vehicles at the stop line on the U-turn segment may not expect vehicles on Route 28 north
to approach the intersection as quickly as they do and accept an unsafe gap.
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High speeds may also contribute to some of the rear-end crashes on Route 28 south. Even though the 85
percentile speed conforms closely to the posted speed on Route 28 south, there are still some outlying vehicles
traveling at speeds greater than 50 or 70 mph. As vehicles merge onto Route 28 south from I-495, they may
have to weave over to the left lane to access Route 28 north via the U-turn segment. This mix of slow, merging
and weaving traffic with high speeds may cause some of the rear-end crashes. The fact that the U-turn
segment’s queue can spill back onto Route 28 south further exacerbates the issue.
Potential Enhancements:
Continue speed enforcement. Andover police says that the interchange of Route 28 and I495 is already a regular spot for speed enforcement in Town. Andover police should
continue to enforce the posted speed limit throughout the area and maintain a common
police presence in order to discourage vehicles from speeding. This is a low-cost and shortterm improvement that can be implemented at any time.
3. Pavement conditions
The pavement condition throughout the interchange of Route 28 and I-495 is in poor condition. With high
volumes of traffic and large trucks using the interchange, rutting and wash boarding symptoms are prevalent.
Of major concern are the pavement around the U-turn segment and the pavement toward the bottom of the I495 north/Route 28 south off-ramp.
As described earlier on in this document, the pavement in the area of the non-marked de facto
storage/deceleration lane for the U-turn segment is in poor condition. As vehicles decelerate along this
segment and turn around the U-turn segment the pavement gets rutted and shoved creating an uneven and
bumpy surface. Consequences include reduced friction and vehicles avoiding the uneven and bumpy surfaces.
Both consequences contribute to rear-end crashes as vehicles may slide on the pavement or as vehicles
decelerate in through lanes while avoiding the uneven and bumpy surface.
Similar pavement conditions are present at the bottom of the I-495 north/Route 28 south off-ramp. As vehicles
approach the horizontal curve at the bottom of the ramp prior to merging onto Route 28 south they are
traveling on a downgrade and attempting to decelerate from highway speeds. Similar to the U-turn segment,
as vehicles brake heavily and navigate the horizontal curve, the pavement becomes rutted and shoved creating
a bumpy and uneven surface. As a consequence, friction is reduced and vehicles may lose control and run off
the ramp. This may have contributed to the single vehicle crashes at the bottom of the ramp.
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Potential Enhancements:
Resurface the interchange. To eliminate the uneven, bumpy, rutted and shoved pavement
the interchange should be resurfaced. Full depth reconstruction may be considered in some
areas where extreme rutting and shoving are occurring. This may eliminate some of the
rear-end crashes and single vehicle run-off-the-road crashes. Resurfacing the interchange is
a long-term and high-cost improvement and it is understood that it will be included within
the resurfacing project.
4. Vegetation
Vegetation throughout the interchange was observed to be overgrown during the RSA. Two areas in particular
were discussed: on the inside of the horizontal curve of the I-495 north/Route 28 south off-ramp and along the
west side of Route 28 just south of the I-495 north/Route 28 south off-ramp.
Vegetation on the inside of the horizontal curve on I-495 north/Route 28 south off-ramp obstructs the view of
the yield line for vehicles traveling down the ramp. Although no crashes reported in this manner, a vehicle may
not be able to see queued traffic at the yield line due to the brush obstructions and cause a rear-end crash.
Furthermore, a pedestrian crosswalk is proposed at the bottom of the ramp as part of the resurfacing project.
With the current conditions the view of pedestrians in the crosswalk will be obstructed by the brush on the
inside of the ramp which may possibly lead to conflicts between vehicles and pedestrians.
Vegetation just south of the I-495 north/Route 28 south off-ramp on the west side of Route 28 is overgrown to
the point where it completely obstructs the sidewalk. During the RSA, attendees were forced to walk in the
shoulder of Route 28 south due to the brush obstructions.
Potential Enhancements:
Trim vegetation throughout the interchange. Vegetation should be trimmed and cut back
to allow adequate sight lines and clear pedestrian paths. This is a low-cost and short-term
enhancement that should be done as part of regular District 4 maintenance before the
resurfacing project.
5. Signage and Pavement Markings
Guide signage throughout the interchange was discussed during the RSA however no major issues were
brought up. A discussion of regulatory and warning signs on the I-495 north/Route 28 south off-ramp revealed
that the yield sign at the merge point of the ramp and Route 28 south is inconspicuous and may contribute to
the side-swipe/angle and rear-end crashes in the area.
Pavement markings were also discussed throughout the interchange. As mentioned before, to prevent vehicles
from accessing the U-turn segment from the I-495 north/Route 28 south off-ramp a solid single white lane line
is provided in between the ramp and the U-turn segment. According to the MUTCD a solid single white lane
line is intended for discouraging vehicles from changing lanes, it does not prohibit it. Also discussed above in
the Interchange Geometry and Control section is the lack of lane definition in the U-turn segment at the stop
line and the need for a deceleration/queue storage lane on Route 28 south. Other pavement markings were
lacking throughout the interchange including a stop line on the U-turn segments, yield lines on all of the offramps and gore markings around the median islands defining the U-turn segments. Although it is difficult to
relate any one crash to pavement markings, lacking pavement markings can add to confusion and may assist in
noncompliance to the laws of the road.
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At present, new ADA-compliant wheelchair ramps and sidewalk are being constructed across Route 28 between
the Burke-Magliozzi Funeral Home and the Chinmaya Maruti Center, just south of the U-turn segments. Under
the resurfacing project, MassDOT will need to ensure that pavement markings and signs associated with the
crossing meet current MUTCD standards and are replicated under the resurfacing contract.
Potential Enhancements:
Provide W3-2 (yield ahead) signs in advance of the yield line on the I-495 north/Route 28
south off-ramp. Providing W3-2 signs will alert drivers of the upcoming yield and may
increase the compliance of the yield sign which may reduce rear-end and side-swipe crashes
at the yield line. Providing two signs, one on each side of the ramp, will increase
conspicuousness. This is a low-cost and short-term enhancement that should be
implemented into the resurfacing project. This enhancement can be implemented on all
ramps throughout the interchange as well.
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Provide two R1-2 (yield) signs at the yield line on the I-495 north/Route 28 south off-ramp.
Currently there is one R1-2 sign at the yield line on the I-495 north/Route 28 south off-ramp.
In order to make the need to yield more conspicuous for drivers a second R1-2 sign may be
added across the ramp from the existing R1-2. This is a low-cost and short-term
enhancement that should be implemented into the resurfacing project. This enhancement
can be implemented on all ramps throughout the interchange as well.
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Define lanes on the U-turn segment as discussed before.
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Provide a formal storage/deceleration lane on Route 28 south for the U-turn segment as
discussed before.
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Provide a solid double white lane line on Route 28 south in the area of the I-495 north offramp as discussed before.
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Provide wide gore lines around the U-turn segments. Providing wide gore lines around the
U-Turn segments will better define the geometry and lanes of the roadway and may reduce
confusion for drivers. This is a low-cost and short-term enhancement that should be
implemented into the resurfacing project.
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Provide stop lines and yield lines at stop signs and yield signs, respectively. Providing stop
bars and yield lines, where appropriate, will highlight the point at which vehicles should stop
and yield which may reduce the compliance of such control. This may reduce the amount of
rear-end crashes and side-swipe angle crashes caused when vehicles fail to yield or stop.
This is a low-cost and short-term enhancement that should be implemented into the
resurfacing project.
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Replace/provide proper signage and markings for the crosswalk under construction south
of the U-turn segments. It is assumed that the crosswalk markings and signage will be up to
date with current MUTCD standards as part of the ongoing project. If not, the resurfacing
project should use the opportunity to implement any sign or marking improvements. This is
a low-cost and short-term improvement.
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6. Pedestrian and Bicycle Accommodations
Pedestrian accommodations were lacking throughout the interchange. Continuous sidewalks run along Route
28 in both directions throughout the entire interchange however there are many obstructions, such as
vegetation and utility poles, forcing pedestrians onto the shoulder of Route 28. Additionally, there are no
wheel chair ramps at curb cuts and intersections. No marked cross walks or pedestrian warning signs are
provided anywhere throughout the interchange. Even though there are no recorded pedestrian crashes within
the interchange, pedestrian safety was discussed as an issue.
The I-495 north/Route 28 south off-ramp was of particular concern in terms of pedestrian safety. Aside from
the above mentioned safety issues, it is difficult for pedestrians to determine if it is safe to cross the ramp do
to the fact that the horizontal curve and the thick vegetation inside the curve blocks the view of any
approaching vehicles. Likewise, vehicles would not see if any pedestrians are crossing. To worsen the issue,
vehicles usually travel at high speeds as they travel down the ramp. Although not discussed, this issue may
exist on other ramps throughout the interchange.
Bicycle accommodations were also lacking throughout the interchange. Shoulders vary in width from eight
feet to one foot forcing bicyclists to ride in the outside travel lane with traffic at times. The layout of the
intersecting ramps from I-495 also pose as a safety issue for bicyclists on Route 28. Bicyclists are forced to mix
with high speed merging vehicles as they cross the merge and diverge points where the off-ramps intersect
Route 28. Although no bicycle crashes were reported during the study period, bicyclists were observed during
the RSA and these safety issues were discussed.
Potential Enhancements:
Trim and cut back vegetation. As discussed earlier, vegetation should be trimmed and cut
back to allow adequate sight lines and clear pedestrian paths, especially in the area of the I495 north/Route 28 south off-ramp. This is a low-cost and short-term enhancement that
should be done as part of regular District 4 maintenance before the resurfacing project.
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Clear obstructions on sidewalks. Clearing obstructions in order to provide at least a 3 foot
minimum clear width along the entirety of all sidewalks will allow safe and uninterrupted
passage for all pedestrians including people with wheelchairs. Utility poles were the most
common obstruction. Ideally, utility poles should be placed in back of the sidewalk.
Relocating utility poles may be a mid-term and medium cost enhancement that will need
coordination with the utility company.
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Provide ADA compliant wheelchair ramps throughout. Currently there is a project in
progress to update all wheelchair ramps in the area. If there is any area of sidewalk that is
not included in the ramp project then it should be upgraded to meet ADA standards as part
of the resurfacing project. This is a mid-term and medium cost enhancement that is
assumed to be included in the resurfacing project.
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Provide crosswalks and pedestrian warning signs where appropriate. Crosswalks should be
placed across all off-ramps to alert drivers of the possible presence of pedestrians.
Crosswalks should be placed at least 4 feet downstream from the stop or yield line.
Advanced pedestrian warning signs should be considered for all crosswalks and pedestrian
crossing signs with downward pointing arrows should be considered at crosswalks not
located at a stop or yield line. As discussed earlier, signs and pavement markings should be
replaced (or provided, if need be) at the crosswalk that is being constructed just south of the
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U-turn segments. This is a short-term and low-cost enhancement that should be
incorporated into the resurfacing project.
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Provide a smaller radius of entry on the I-495 north/Route 28 south off-ramp. As discussed
earlier, having the I-495 north off-ramp intersect Route 28 south at a smaller radius, say 30
degrees, will not only allow drivers to easily view oncoming traffic on Route 28 south at the
yield line but it will also allow vehicles to better view pedestrians and bicyclists. Vehicles will
be more likely to stop and yield to pedestrians and bicycles. Furthermore, crosswalks can
more easily be placed at the point of yield and bicyclists will not need to mix with high speed
merging traffic at the merge and diverge points. This is a long-term and high-cost
enhancement that is outside of the scope of the resurfacing project. This enhancement may
also be considered for all ramps throughout the interchange.
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Provide consistent five foot shoulders for bicyclist. At least five foot shoulders should be
provided throughout the interchange to provide bicycle accommodations. Special attention
should be considered where I-495 ramps merge and diverge with Route 28 and bicyclists
must cross merging and diverging traffic. Depending on the width of the cross section and
the need for widening, this may be a short-term and low-cost enhancement that should be
incorporated into the resurfacing project or it may be a long-term high-cost enhancement
that is outside of the scope of the resurfacing project.
7. Highway Lighting
Six out of the 33 crashes reported at the interchange of I-495 north and Route 28 occurred at night. Although
these six crashes only account for about 18% of the total crashes, the lack of lighting throughout the
interchange was discussed during the RSA. According to MassDOT District 4 staff there is a damaged and nonfunctioning highway lighting load center along Route 28 south just south of the I-495 off ramp. It is estimated
that this load center powered about 10 highway lights throughout the interchange when it was functional.
Currently there is no lighting anywhere within the interchange which may contribute to some of the night time
crashes.
Potential Enhancements:
Provide highway lighting throughout the interchange. Providing lighting throughout the
interchange will increase the visibility of any vulnerable road users (pedestrians and
bicyclists) and will allow drivers to quickly assess roadway conditions at night. This will make
the interchange safer and may possibly reduce the number of crashes occurring at night. It
should be determined if the existing non-functioning highway lighting load center can be
reused. This is a potentially long-term and high-cost enhancement that is outside the scope
of the resurfacing project.
A list of all safety issues discussed and all potential enhancements is provided below in Table 2. Safety payoff
estimates are subjective and are based on the relative percent of crashes that may be reduced by the
enhancement; for example, low (<30%), medium (31% to 70%), and high (>71%). The time frame is categorized as
short-term (<1 year), mid-term (1 to 3 years), or long-term (>3 years). The costs are categorized as low (<$10,000),
medium ($10,001 to $50,000), or high (>$50,001). Enhancements that are not to be included in this resurfacing
project should be considered in a future project that may possibly occur.
11
Table 2. Summary of safety issues and enhancements.
Safety Issue
No Route 28 SB to I-495
NB or I-495 to Route
28NB
Angle crashes between
the U-turn segment and
Route 28 north
Queue spillback from Uturn segment
Vehicles stacking side
by side at U-turn
segment’s stop line
Vehicles accessing the
U-turn segment from the
I-495 north/Route 28
south ramp
Rear-end crashes and
vehicles failing to yield at
the I-495 north/Route 28
south ramp
Safety Enhancement
Safety Payoff
Time Frame
Cost
Reconstruct entire interchange to a single
point urban interchange (SPUI)
High
Long
High
Construct new ramps for Route 28 SB to I­
495 NB and I-495 to Route 28NB
High
Long
High
Signalize the intersection of Route 28 north
and the U-turn segment
High
Long
High
Mount flashing beacons overhead
Low
Medium
High
Reduce Route 28 north to one lane at the Uturn segment.
Medium
Short
Low
Provide a formal storage/deceleration lane on
Route 28 south for the U-turn segment
Low
Short
Low
Signalize the intersection of Route 28 north
and the U-turn segment
High
Long
High
Define lanes on the U-turn segment
Low
Short
Low
Provide a solid double white lane line in the
area of the I-495 north/Route 28 south ramp
Low
Short
Low
Provide a R4-9 (STAY IN LANE) sign to
supplement the solid double white lane line
Low
Short
Low
Extend the gore of the I-495 north/Route 28
south off-ramp downstream past the U-turn
segment
Low
Short/Long
Low/High
Lessen the angle of entry on the I-495 north
ramp with Route 28 south
High
Long
High
Provide W 3-2 (yield ahead) signs on the I-495
north/Route 28 south ramp
Low
Short
Low
Provide a yield line
Low
Short
Low
Provide two R1-2 (yield) signs at the yield line
Low
Short
Low
12
Safety Issue
Safety Enhancement
Safety Payoff
Time Frame
Cost
Vehicles running off the
road at the end of the
Provide two R1-2 (yield)
signs at the yield line
Lessen the angle of entry on the I-495 north
ramp with Route 28 south
High
Long
High
High speeds throughout
the interchange
Continue strict speed enforcement in the area
Low
Short
Low
Poor pavement
conditions
Resurface the interchange
Medium
Long
High
Vegetation overgrowth
Trim vegetation throughout the interchange
Medium
Short
Low
Lacking pavement
markings including stop
lines, yield lines and
gore lines
Provide gore pavement markings around the
islands of the U-turn segments and provide
stop and yield lines where appropriate.
Low
Short
Low
Medium
Short
Low
Move obstructions, such as utility poles, off of
sidewalk or provide at least three feet of clear
space
Low
Long
High
Provide ADA compliant wheelchair ramps at
all curb cuts and intersections
High
Long
High
Provide marked crosswalks where
appropriate
Low
Short
Low
Provide pedestrian warning signs where
appropriate
Low
Short
Low
Clear vegetation from the inside of the curve
on the I-495 north/Route 28 south ramp to
open sight lines
Medium
Short
Low
Lessen the angle of entry on the I-495 north
ramp with Route 28 south to provide more
ideal crosswalk placement
High
Long
High
Provide a consistent shoulder throughout the
interchange, five feet wide at least
Medium
Short/Long
Low/High
Lessen the angle of entry on the I-495 north
ramp with Route 28 south so bicyclist will not
have to mix with high speed merging traffic
High
Long
High
Medium
Long
High
Obstructions in sidewalk
forcing pedestrians to
walk in roadway
Lacking wheelchair
ramps
Pedestrians along Route
28 crossing I-495 offramps
Lacking bicycle
accommodations
Lacking highway lighting
Trim vegetation away from sidewalks
Provide highway lighting throughout the
interchange. Determine if the existing nonfunctioning load center can be reused.
13
APPENDIX I
CRASH DIAGRAMS AND SUMMARIES
Road Safety Audit
Andover, MA
Route 28 (Union St/N Main St) at Interstate 495
Meeting Location: Andover Public Safety Center
32 North Main Street, Andover, MA
Wednesday, June 24th 2015
1:00 PM – 3:00 PM
Type of meeting:
High Crash Location – Road Safety Audit
Attendees:
Invited Participants to Comprise a Multidisciplinary Team
Please bring:
Thoughts and Enthusiasm!!
1:00 PM
Welcome and Introductions
1:15 PM
Discussion of Safety Issues
 Crash history, Speed Regulations – provided in advance
 Existing Geometries and Conditions
2:00 PM
Site Visit
 Drive to the intersection
 As a group, identify areas for improvement
2:30 PM
Discussion of Potential Improvements
 Discuss observations and finalize safety issue areas
 Discuss potential improvements and finalize recommendations
3:00 PM
Adjourn for the Day – but the RSA has not ended
Instructions for Participants:
 Before attending the RSA on June 24th, participants are encouraged to drive/walk
through the intersection and complete/consider elements on the RSA Prompt List
with a focus on safety.
 All participants will be actively involved in the process throughout. Participants
are encouraged to come with thoughts and ideas, but are reminded that the
synergy that develops and respect for others’ opinions are key elements to the
success of the overall RSA process.
 After the RSA meeting, participants will be asked to comment and respond to the
document materials to assure it is reflective of the RSA completed by the
multidisciplinary team.
Andover, MA
•/}Jf.I!J.l!~-!!2QI
I
1-495 NB Ramps at Rt 28
:ighway Division
REGION: Merrimack Valley Planning Commission
TIME PERIOD ANAL.YlED: 2011-2013
SOURCE OF CRASH REPORT'S: STAlE and LOCAL POLICE Report.
COLLISION DIAGRAM
DAlE PREPARED: 05/28/2015
PREPARED BY: William Ullom
SYMBOLS
TYPES OF CRASH
11+1
• Moving Vehicle
~
-
Bicycle
Head on
~
((( • Backing Vehicle
- - -+ Nan-Involved Vehicle
~ Pedntrlan
SEVERITY
•
___.../
Rear End
Angle
~ Turning
Injury Movement
Animal
~Sideswipe
~
Parkecl Vehicle
0
D
Fixed Object
0 •
•
0
Out of Control
Night Time Crash
0
Fatal N
Crash Data Summary Table
I-495 NB Ramps at Rt 28, Andover, MA
January 1, 2011- December 31, 2013
Crash
Date
Crash Day
m/d/y
Time of Day
1
1/28/11
Friday
8:58 AM
Angle
Daylight
Rain
2
2/4/11
Friday
3:07 PM
Rear-end
Daylight
Rain
3
4
2/6/11
5/9/11
Sunday
Monday
8:31 PM
7:13 AM
Single Vehicle Crash
Single Vehicle Crash
Dark - lighted roadway Clear
Daylight
Clear
Wet
Dry
5
6
7
8
5/18/11
6/16/11
6/21/11
9/13/11
Wednesday
Thursday
Tuesday
Tuesday
3:19 PM
6:52 PM
12:23 PM
11:54 AM
Sideswipe, opposite direction
Angle
Angle
Single Vehicle Crash
Daylight
Daylight
Daylight
Daylight
Rain
Clear
Clear
Clear
9
10
11
12
9/22/11
12/22/11
1/6/12
4/7/12
Thursday
Thursday
Friday
Saturday
7:38 PM
3:03 PM
4:12 PM
9:15 AM
Angle
Angle
Angle
Angle
Dark - lighted roadway
Daylight
Daylight
Daylight
13
14
15
5/3/12
6/16/12
7/2/12
Thursday
Saturday
Monday
11:13 PM
2:05 PM
5:46 PM
16
17
18
19
20
7/3/12
7/18/12
8/2/12
9/23/12
12/1/12
Tuesday
Wednesday
Thursday
Sunday
Saturday
21
22
23
24
25
26
27
1/9/13
1/10/13
2/27/13
7/18/13
8/25/13
9/26/13
10/14/13
28
11/7/13
29
Crash
Diagram
Ref #
Manner of Collision
Type
Light Condition
Type
Weather
Condition
Type
Road Surface
Driver Contributing Code
Type
Type
Water
(standing,
moving)
Other improper action
Water
(standing,
moving)
Inattention
Ages
D1
D2
48
84
52
55
Comments
32
50
Vehicle hit ice, lost control, and hit snowbank
Vehicle hit utility pole.
Wet
Dry
Dry
Dry
No Improper Driving
Inattention
Operating Vehicle in erratic, reckless,
careless, negligent, or aggressive
manner
Failed to yield right of way
Failed to yield right of way
Over-correcting/over-steering
19
20
48
19
30 UNK
48
MV 2 ran stop sign and crashed into MV 1.
MV 2, turning left, hit MV 1 after stopping at stop sign.
MV 2 going straight to I-495N hit MV 1 and then fled.
MV 1 swerved after she thought she saw another vehicle.
Rain
Clear
Clear
Clear
Wet
Dry
Dry
Dry
Failed to yield right of way
Failed to yield right of way
Inattention
Visibility Obstructed
27
16 MV 2 going straight to I-495N hit MV 1.
67 UNK MV 1 going straight to I-495N hit MV 2 and then fled.
25
19 MV 2 going straight to I-495N hit MV 1.
20
22
Single Vehicle Crash
Single Vehicle Crash
Rear-end
Dark - lighted roadway Rain
Daylight
Clear
Daylight
Clear
Wet
Dry
Dry
29
16
41
Slid on wet ramp, hit curb, and flipped.
Collision with utility pole.
30 MV 1 rearended at stop sign, MV 2 thought MV 1 would enter traffic.
6:59 AM
3:42 PM
1:55 PM
4:34 PM
3:04 PM
Rear-end
Angle
Angle
Single Vehicle Crash
Sideswipe, same direction
Clear
Clear
Clear
Clear
Snow
Dry
Dry
Dry
Dry
Wet
23
48
73
53
42
20 Road rage.
39 MV 2 going straight to I-495N hit MV 1.
19 MV 2 going straight to I-495N hit MV 1.
Motorcycle lost ontol on off ramp.
68 MV 2 merged into MV 1.
Wednesday
Thursday
Wednesday
Thursday
Sunday
Thursday
Monday
6:45 PM
10:35 AM
8:10 AM
9:04 AM
1:44 PM
5:05 PM
12:21 PM
Rear-end
Angle
Rear-end
Rear-end
Rear-end
Angle
Angle
Daylight
Daylight
Daylight
Daylight
Daylight
Dark - roadway not
lighted
Daylight
Daylight
Daylight
Daylight
Daylight
Daylight
Inattention
Inattention
Inattention
Operating Vehicle in erratic, reckless,
careless, negligent, or aggressive
manner
Failed to yield right of way
Failed to yield right of way
Unknown
Other improper action
Cloudy
Clear
Rain
Clear
Clear
Clear
Clear
Dry
Dry
Wet
Dry
Dry
Dry
Dry
Followed too closely
Other improper action
Inattention
Inattention
Inattention
Inattention
Failed to yield right of way
41
20
33
49
26
23
54
47
59
27
28
57
20
74
Thursday
4:01 PM
Angle
Daylight
Rain
Wet
25
11/13/13 Wednesday
6:34 PM
Single Vehicle Crash
Daylight
Clear
Dry
Inattention
Swerving or avoiding due to wind,
slippery surface, vehicle, object, nonmotorist in roadway, etc.
53
MV 1 swerved to avoid colliding with unknown MV from 495NB off-ramp, hits
stop sign.
30
31
11/29/13 Friday
12/1/13 Sunday
6:04 PM
9:09 AM
Angle
Single Vehicle Crash
Dark - lighted roadway Clear
Daylight
Cloudy
Dry
Ice
Visibility Obstructed
Driving too fast for conditions
36
26
21 MV 1 turned into U-turn section on N. Main St. from wrong lane, hit by MV 2.
Veh lost control control on ice, hit utility box.
32
12/8/13
7:12 PM
Rear-end
Dark - lighted roadway Clear
Dry
Other improper action
45
25 MV 1 stopped to yeild and MV2 thought MV 1 had pulled into traffic.
33
12/18/13 Wednesday
6:16 PM
Sideswipe, same direction
Dark - lighted roadway Cloudy
Dry
Inattention
61
56
Sunday
Summary based on Crash Reports obtained from the state and local police reports.
Rear end on NB I-495 off-ramp.
MV 2 merged into MV 1.
MV 2 rear ended MV 1 while MV 1 was at yield line.
MV 2 going straight to I-495N hit MV 1.
MV 2 going straight to I-495N hit MV 1.
MV 2 stopped at stop sign to turn left onto Rt 28 NB,alongside another
vehicle. MV 2 does not see MV 1 coming up Rt 28 NB and pulls out and hits
57 MV 1.
Crash Data Summary Tables and Charts
I-495 NB Ramps at Rt 28, Andover, MA
CRASH MONTH
16%
14%
12%
10%
8%
6%
4%
2%
0%
15%
12%
12%
9%
9%
12%
9%
9%
6%
3%
3%
0%
J
F
M
A
M
J
J
A
S
O
N
D
CRASH DAY OF WEEK
27%
30%
25%
18%
20%
15%
15%
10%
12%
9%
9%
Monday
Tuesday
9%
5%
0%
Wednesday
Thursday
Friday
Saturday
Sunday
CRASH TIME OF DAY
25%
21%
18%
20%
15%
15%
15%
10%
12%
6%
6%
3%
5%
3%
0%
0%
0%
0%
6AM- 8AM
45%
40%
35%
30%
25%
20%
15%
10%
5%
0%
8AM­
10AM
10AM­
12PM
12PM­
2PM
2PM- 4PM 4PM- 6PM 6PM- 8PM
8PM­
10PM
10PM­
12AM
12AM­
2AM
2AM- 4AM 4AM- 6AM
CRASH MANNER OF COLLISION
42%
24%
24%
6%
Single
Vehicle
Crash
Rear-end
Angle
Sideswipe,
same
direction
Crash Data Spreadsheet_Rt 28 @ I-495_05_28_2015FINAL.xlsx2 of 3
3%
Sideswipe,
opposite
direction
0%
Head on
0%
0%
Rear to Rear Unknown
5/28/2015
Crash Data Summary Tables and Charts
I-495 NB Ramps at Rt 28, Andover, MA
CRASH LIGHT CONDITION
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
79%
18%
Daylight
0%
0%
3%
Dawn
Dusk
Dark ­
Dark ­
Dark ­
Lighted Roadway not unknown
Roadway
lighted
roadway
lighting
0%
0%
0%
Other
Unknown
CRASH WEATHER CONDITION
70%
60%
50%
40%
30%
20%
10%
0%
67%
21%
9%
Clear
Cloudy
3%
Rain
0%
0%
0%
0%
Severe
Blowing
Sleet, Hail, Fog, Smog,
Smoke
Crosswinds sand, snow
Freezing
Rain
Snow
0%
0%
Other
Unknown
CRASH ROAD SURFACE
80%
70%
60%
50%
40%
30%
20%
10%
0%
70%
21%
Dry
Wet
0%
3%
Snow
Ice
6%
0%
Sand, mud, Water
dirt, oil, (standing,
gravel
moving)
0%
0%
0%
Slush
Other
Unknown
CRASH DRIVER AGES
35%
30%
25%
20%
15%
10%
5%
0%
30%
18%
16%
16%
10%
5%
15-20
21-29
30-39
40-49
Crash Data Spreadsheet_Rt 28 @ I-495_05_28_2015FINAL.xlsx3 of 3
50-59
60-69
3%
70-79
2%
80+
5/28/2015
14
APPENDIX II
SPEED AND VOLUME DATA
Page 1
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
Direction 1
Start
Time
06/25/15
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12 PM
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Total
Percent
AM Peak
Vol.
PM Peak
Vol.
Grand
Total
Percent
Statistics
1
29
30
15
13
8
10
28
54
99
90
117
146
156
149
175
138
167
179
183
181
140
133
176
96
31
2514
17.1%
11:00
156
17:00
183
30
32
5
5
4
2
5
17
24
61
83
55
86
56
73
59
65
79
71
97
92
71
63
54
31
8
1166
7.9%
10:00
86
17:00
97
2514
1166
17.1%
7.9%
33
35
9
13
7
6
6
14
34
46
84
50
69
41
56
34
58
51
69
46
52
54
46
51
53
22
971
6.6%
08:00
84
16:00
69
36
38
33
21
14
9
5
22
52
91
112
124
96
98
74
74
89
101
104
105
109
86
69
111
74
41
1714
11.6%
09:00
124
21:00
111
971
1714
6.6%
11.6%
15th Percentile :
50th Percentile :
85th Percentile :
95th Percentile :
10 MPH Pace Speed :
Number in Pace :
Percent in Pace :
Number of Vehicles > 35 MPH :
Percent of Vehicles > 35 MPH :
Mean Speed(Average) :
39
41
34
19
25
10
8
32
57
116
147
167
120
125
132
128
163
146
174
189
177
163
114
192
107
49
2594
17.6%
09:00
167
21:00
192
2594
17.6%
11 MPH
25 MPH
42 MPH
46 MPH
37-46 MPH
4037
27.4%
10082
68.5%
27 MPH
42
44
29
25
17
6
10
35
82
128
144
135
111
114
154
140
131
178
181
206
251
177
176
195
111
54
2790
18.9%
08:00
144
18:00
251
45
47
19
17
10
2
10
25
64
52
78
76
75
66
108
86
85
93
129
135
151
115
106
121
45
25
1693
11.5%
08:00
78
18:00
151
48
50
5
5
10
1
7
12
28
29
17
40
28
42
51
47
38
52
59
56
67
53
49
54
27
12
789
5.4%
11:00
42
18:00
67
51
53
7
2
2
1
6
5
12
11
6
21
9
7
13
16
12
20
27
20
28
16
13
32
9
13
308
2.1%
09:00
21
21:00
32
Untitled S
Site Code: 00000011
Station ID:
Date Printed: 26-Jun-15
Untitled S
Untitled S
54
56
1
0
2
0
0
5
6
3
1
3
3
4
6
8
3
10
10
6
5
2
5
9
11
6
109
0.7%
06:00
6
22:00
11
57
59
2
0
2
1
0
1
1
2
1
5
2
0
5
0
5
3
2
2
8
4
4
6
1
3
60
0.4%
09:00
5
18:00
8
60
62
0
0
0
0
0
0
1
0
1
1
0
0
0
1
0
1
2
2
0
0
1
0
3
0
13
0.1%
06:00
1
22:00
3
63
65
0
0
1
0
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
3
0.0%
02:00
1
66
999
2
0
0
0
0
0
0
0
0
0
0
0
1
0
0
1
0
1
1
1
0
0
2
0
9
0.1%
00:00
2
22:00
2
2790
1693
789
308
109
60
13
3
9
18.9%
11.5%
5.4%
2.1%
0.7%
0.4%
0.1%
0.0%
0.1%
Total
176
122
107
46
67
196
416
638
764
795
745
709
822
768
787
902
1007
1048
1122
882
779
1001
570
264
14733
09:00
795
18:00
1122
14733
85th
Percent
42
43
44
40
45
43
44
42
42
42
40
41
42
42
42
42
43
42
43
43
43
43
42
44
95th
Percent
47
46
49
45
50
48
48
46
45
47
45
46
47
46
46
47
47
46
47
47
47
47
47
50
Page 1
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
Start
Time
12:00 AM
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00 PM
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
Total
Percentage
AM Peak
Vol.
PM Peak
Vol.
Total
22-Jun-15
Mon
23-Jun-15
Tue
24-Jun-15
Wed
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
-
0
0
25-Jun-15
Thu
178
123
107
47
67
197
417
648
769
801
749
716
824
778
789
907
1012
1058
1125
888
781
1005
572
265
14823
100.6%
09:00
801
18:00
1125
Untitled Vo
Site Code: 00000011
Station ID:
Date Printed: 26-Jun-15
Untitled Vo
Untitled Vo
26-Jun-15
Fri
Weekday
Average
27-Jun-15
Sat
4
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
4
0.0%
00:00
4
91
123
107
47
67
197
417
648
769
801
749
716
824
778
789
907
1012
1058
1125
888
781
1005
572
265
-
28-Jun-15
Sun
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
-
-
-
Page 1
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
rte28nb june2015
Site Code: 00000011
Station ID:
Date Printed: 26-Jun-15
rte28nb june2015
rte28nb june2015
Date\Speed
(MPH)
6/25/2015
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Day Total
1-10
11-15
16-20
21-25
26-30
31-35
36-40
41-45
46-50
51-55
56-60
61-65
66-70
>70
0
0
0
0
0
0
0
0
0
2
0
1
0
0
0
0
0
0
0
0
0
0
0
0
3
0
0
0
0
0
1
0
2
1
0
3
0
0
0
0
0
0
0
1
1
0
0
0
0
9
2
0
0
0
0
0
0
1
6
10
2
1
3
2
0
1
0
0
0
0
0
3
5
2
38
7
6
3
1
5
6
6
15
19
28
38
38
43
43
38
34
45
44
38
44
40
67
30
13
651
12
10
9
7
7
25
56
95
88
95
129
138
120
137
109
146
155
160
156
110
106
114
57
16
2057
13
17
10
7
9
24
47
86
134
81
122
68
106
72
99
97
104
106
114
96
86
82
78
27
1685
52
35
30
15
11
43
82
168
207
232
179
177
161
154
211
185
216
226
234
179
139
236
154
63
3389
54
34
30
10
15
55
133
190
229
215
182
194
237
221
205
274
286
323
372
286
259
308
155
91
4358
14
18
16
3
14
28
68
58
62
95
69
74
121
100
90
111
145
142
149
129
116
129
55
27
1833
8
2
4
1
6
9
17
12
7
24
12
9
18
21
14
28
34
26
32
18
17
41
19
17
396
2
0
2
1
0
2
3
4
1
5
2
2
6
3
6
5
6
4
9
4
6
6
4
5
88
0
0
1
0
0
0
1
0
1
2
0
0
0
1
0
1
1
0
0
0
0
0
1
0
9
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
1
1
1
0
0
0
0
5
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
2
0
4
6/26/2015
Lane1 Total
0
3
1
10
0
38
2
653
16
2073
14
1699
41
3430
42
4400
19
1852
1
397
1
89
2
11
0
5
Lane1
Total
166
122
105
45
67
193
413
631
755
789
738
702
816
754
772
883
992
1032
1106
868
769
986
560
261
14525
0
139
4 14664
85 percentile = 45
Page 1
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
Direction 1
Start
Time
06/25/15
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12 PM
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Total
Percent
AM Peak
Vol.
PM Peak
Vol.
Grand
Total
Percent
Statistics
1
20
2
0
3
1
1
4
3
3
2
7
13
11
5
11
6
15
1
2
6
11
8
8
1
2
126
0.9%
10:00
13
15:00
15
21
22
0
2
0
1
2
2
7
13
10
8
4
11
11
13
7
7
7
1
3
10
8
6
2
5
140
1.0%
07:00
13
13:00
13
126
140
0.9%
1.0%
23
24
2
1
2
0
3
15
14
31
13
13
14
34
39
27
24
23
22
10
16
13
14
13
8
6
357
2.5%
11:00
34
12:00
39
25
26
8
3
1
4
12
31
41
59
27
36
49
47
50
49
65
53
41
26
38
37
35
35
15
15
777
5.4%
07:00
59
14:00
65
357
777
2.5%
5.4%
15th Percentile :
50th Percentile :
85th Percentile :
95th Percentile :
10 MPH Pace Speed :
Number in Pace :
Percent in Pace :
Number of Vehicles > 35 MPH :
Percent of Vehicles > 35 MPH :
Mean Speed(Average) :
27
28
12
6
4
13
20
74
61
89
60
69
85
90
98
80
92
94
55
69
64
72
47
56
34
16
1360
9.4%
11:00
90
12:00
98
1360
9.4%
26 MPH
32 MPH
37 MPH
40 MPH
29-38 MPH
9209
64.4%
4449
31.1%
32 MPH
29
30
13
7
8
3
32
77
99
116
115
98
101
110
101
108
126
121
103
102
88
68
61
62
50
17
1786
12.4%
07:00
116
14:00
126
31
32
11
1
4
9
32
110
134
147
148
106
109
148
103
123
146
127
145
121
106
106
67
69
61
18
2151
14.9%
08:00
148
14:00
146
33
34
20
6
8
11
19
80
133
179
170
142
120
119
159
126
130
141
141
142
120
84
75
66
35
19
2245
15.5%
07:00
179
12:00
159
35
36
5
11
8
9
20
84
106
140
153
120
107
94
136
105
124
137
156
144
101
72
71
61
32
18
2014
13.9%
08:00
153
16:00
156
Untitled S
Site Code: 00000090
Station ID:
Date Printed: 26-Jun-15
Untitled S
Untitled S
37
38
10
6
2
5
18
56
105
128
118
95
73
85
95
76
92
82
127
130
97
86
66
49
26
18
1645
11.4%
07:00
128
17:00
130
39
40
13
3
3
2
7
50
73
80
68
55
47
51
59
58
58
57
65
73
70
49
35
27
7
8
1018
7.0%
07:00
80
17:00
73
41
42
6
1
4
3
6
26
36
31
49
25
18
22
21
30
24
27
23
39
36
28
15
13
6
6
495
3.4%
08:00
49
17:00
39
43
44
2
1
2
1
2
9
21
13
13
10
2
5
9
5
9
11
7
13
11
13
9
10
4
3
185
1.3%
06:00
21
17:00
13
45
999
3
3
1
0
6
13
11
10
9
9
3
3
5
7
6
9
8
18
10
8
7
3
3
2
157
1.1%
05:00
13
17:00
18
1786
2151
2245
2014
1645
1018
495
185
157
12.4%
14.9%
15.5%
13.9%
11.4%
7.0%
3.4%
1.3%
1.1%
Total
107
51
50
62
180
631
844
1039
955
793
745
830
891
818
909
904
901
890
766
657
518
478
284
153
14456
07:00
1039
14:00
909
14456
85th
Percent
39
37
37
36
37
38
38
37
38
37
36
37
37
37
37
37
37
38
38
38
37
37
36
37
95th
Percent
41
39
41
40
40
40
40
40
40
40
39
39
39
40
39
40
39
40
40
40
40
40
38
40
Page 1
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
Rte28SB June2015
Site Code: 00000090
Station ID:
Date Printed: 26-Jun-15
Rte28SB June2015
Rte28SB June2015
Date\Speed
(MPH)
6/25/2015
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Day Total
1-5
6-10
11-15
16-20
21-25
26-30
31-35
36-40
41-45
46-50
51-55
56-60
61-65
>65
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
3
0
0
1
0
1
1
0
1
0
2
1
1
2
0
0
7
1
1
2
0
0
1
0
0
22
2
0
0
1
0
1
3
1
1
5
11
8
3
8
5
4
0
1
2
11
5
5
1
2
80
4
3
2
3
9
23
36
69
35
36
35
69
73
71
55
55
44
21
35
39
36
37
17
19
826
31
16
13
18
60
176
186
239
190
188
218
223
226
206
259
243
184
187
174
161
129
135
92
40
3594
35
11
18
22
66
231
314
402
393
310
284
316
339
302
344
338
353
340
270
224
183
164
116
50
5425
24
16
7
14
30
149
237
272
264
208
172
181
213
186
206
206
281
270
224
173
131
108
45
31
3648
9
2
6
4
10
39
58
48
66
37
22
29
32
39
37
43
33
60
49
44
28
23
12
9
739
1
3
0
0
4
7
10
6
5
7
0
1
3
3
2
2
4
9
8
4
3
3
1
1
87
0
0
1
0
0
2
0
0
0
0
1
0
0
0
0
2
1
1
0
1
0
0
0
1
10
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
6/26/2015
Lane1 Total
0
0
0
3
1
23
3
83
4
830
23
3617
29
5454
21
3669
9
748
1
88
1
11
1
2
0
0
Lane1
Total
107
51
48
62
180
629
844
1038
955
793
744
828
891
815
908
902
901
890
764
657
515
476
284
153
14435
0
93
0 14528
85 percentile = 37
Page 1
Rte28SB June2015
Site Code: 00000090
Station ID:
Date Printed: 26-Jun-15
Rte28SB June2015
Rte28SB June2015
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
Direction 1
Report for 6/25/2015 12:01:00 AM to 6/25/2015 11:59:00 PM
SPEED STATISTICS - 15 to 70+ by 5 MPH
Speed in 1 - 15
MPH
Count
25
Percent
0.2
15
Over Speed
Count 14406
Percent 99.8
Percentile
Speed
5%
25
Average 33
(Mean)
Pace 28-37
Speed
Number in 9874
Pace
Percent in 68.4
Pace
16 - 20 21 - 25 26 - 30 31 - 35 36 - 40 41 - 45 46 - 50 51 - 55 56 - 60 61 - 65 66 - 70 71 - 75
80
0.6
825
5.7
3594
24.9
5422
37.6
3648
25.3
739
5.1
87
0.6
10
0.1
1
0.0
0
0.0
0
0.0
0
0.0
76 ­
999
0
0.0
20
14326
99.3
25
13501
93.6
30
9907
68.7
35
4485
31.1
40
837
5.8
45
98
0.7
50
11
0.1
55
1
0.0
60
0
0.0
65
0
0.0
70
0
0.0
75
0
0.0
999
0
0.0
10%
27
15%
28
45%
32
50%
33
55%
34
85%
38
90%
39
95%
41
Page 2
Rte28SB June2015
Site Code: 00000090
Station ID:
Date Printed: 26-Jun-15
Rte28SB June2015
Rte28SB June2015
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
COMBINED - Direction 1
Report for 6/25/2015 12:01:00 AM to 6/25/2015 11:59:00 PM
SPEED STATISTICS - 15 to 70+ by 5 MPH
Speed in 1 - 15
MPH
Count
25
Percent
0.2
15
Over Speed
Count 14406
Percent 99.8
Percentile
Speed
5%
25
Average 33
(Mean)
Pace 28-37
Speed
Number in 9874
Pace
Percent in 68.4
Pace
16 - 20 21 - 25 26 - 30 31 - 35 36 - 40 41 - 45 46 - 50 51 - 55 56 - 60 61 - 65 66 - 70 71 - 75
80
0.6
825
5.7
3594
24.9
5422
37.6
3648
25.3
739
5.1
87
0.6
10
0.1
1
0.0
0
0.0
0
0.0
0
0.0
76 ­
999
0
0.0
20
14326
99.3
25
13501
93.6
30
9907
68.7
35
4485
31.1
40
837
5.8
45
98
0.7
50
11
0.1
55
1
0.0
60
0
0.0
65
0
0.0
70
0
0.0
75
0
0.0
999
0
0.0
10%
27
15%
28
45%
32
50%
33
55%
34
85%
38
90%
39
95%
41
Page 1
Andover Police Department
32 North Main St
Andover, MA 01810
(978)475-0411
Start
Time
12:00 AM
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00 PM
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
Total
Percentage
AM Peak
Vol.
PM Peak
Vol.
Total
22-Jun-15
Mon
23-Jun-15
Tue
24-Jun-15
Wed
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
-
0
0
25-Jun-15
Thu
107
51
50
62
180
631
844
1040
955
793
746
830
891
819
910
904
901
890
766
657
519
478
284
153
14461
100.0%
07:00
1040
14:00
910
Untitled Vo
Site Code: 00000090
Station ID:
Date Printed: 26-Jun-15
Untitled Vo
Untitled Vo
26-Jun-15
Fri
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
Weekday
Average
107
51
50
62
180
631
844
1040
955
793
746
830
891
819
910
904
901
890
766
657
519
478
284
153
27-Jun-15
Sat
28-Jun-15
Sun
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
0
0.0%
-
-
-
-