HomeMy WebLinkAbout2012-11-20 Planning Board Supplemental Materials (46)
TRAFFIC IMPACT AND ACCESS STUDY
PROPOSED DUNKIN’ DONUTS
NORTH ANDOVER, MASSACHUSETTS
181 BALLARDVALE STREET, SUITE 202
WILMINGTON, MASSACHUSETTS 01887
(978) 570-2999
PREPARED FOR:
JFJ Holdings, LLC
751 Main Street, Suite B
Sanford, Maine 04073
AUGUST 2012
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TECHNICAL MEMORANDUM
Greenman-Pedersen, Inc.
181 BALLARDVALE STREET, SUITE 202, WILMINGTON, MA 01887 TELEPHONE: (978) 570-2999 FACSIMILE: (978) 659-3044
An Equal Opportunity Employer
REF: MAX-2012066
DATE: August 13, 2012
TO: Mr. Greg Nolan
JFJ Holdings, LLC
751 Main Street, Suite B
Sanford, Maine 04073
FROM: Ms. Heather L. Monticup, P.E., Project Manager
Mr. Jason R. Plourde, P.E., Senior Project Manager
RE: Traffic Impact and Access Study
Proposed Dunkin’ Donuts
1018 Osgood Street - North Andover, Massachusetts
INTRODUCTION
Greenman-Pedersen, Inc. (GPI) has prepared this Traffic Impact and Access Study (TIAS) for a
proposed Dunkin’ Donuts to be relocated from within the Shell gasoline station plaza
(982 Osgood Street) to 1018 Osgood Street (Routes 125/133) in North Andover, Massachusetts.
The site currently contains a residential home and garage. As proposed, the existing buildings
will be razed and a 2,250 square foot Dunkin’ Donuts with a drive-through window will be
constructed. This TIAS has been prepared to evaluate the traffic impacts and access/egress
requirements for the proposed Dunkin’ Donuts development.
The proposed site is bounded by a commercial/retail/office building (1060 Osgood Street) to the
north, commercial businesses (1000 Osgood Street) to the south, Lawrence Municipal Airport to
the west, and Osgood Street to the east. Access to and egress from the site is currently provided
via one full-access/egress driveway at the southern end of the property. As proposed, the existing
driveway will be shifted slightly to the north as well as modified to an exit-only driveway and a
full access/egress driveway is proposed on the northern end of the property. The site location in
relation to the surrounding roadways is shown on the map on Figure 1.
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GPI Greenman-Pedersen, Inc. Figure 1
Engineers, Architects, Planners, Construction Engineers & Inspectors Site Location Map
SITE
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Since the site abuts and proposes to have access on Osgood Street, a state-maintained roadway,
the project is expected to require a State Highway Access Permit from the Massachusetts
Department of Transportation (MassDOT) District 4 office. Based on the net increases in daily
traffic and in parking spaces as a result of the proposed Dunkin’ Donuts project, the
Massachusetts Environmental Policy Act (MEPA) Transportation review thresholds set forth in
301 CMR 11.10(6)(b) for the preparation of an Environmental Notification Form (ENF) are not
expected to be exceeded. Therefore, approvals are expected to be required through the Town of
North Andover and MassDOT permitting processes.
EXISTING CONDITIONS
Study Area
Evaluation of the traffic impacts associated with the proposed project requires an evaluation of
existing and projected traffic volumes on the adjacent streets, the volume of traffic expected to be
generated by the project, and the impact that this traffic will have on the adjacent streets. In
preparing this TIAS for the Dunkin’ Donuts project, the proposed site driveways were analyzed
and evaluated, as the restaurant is being relocated from two parcels south of the proposed site on
the same side of Osgood Street.
Osgood Street is an Urban Principal Arterial roadway that runs in a general north/south direction.
The roadway is state-maintained and generally provides approximately 46 feet of overall
pavement width with a posted speed limit of 40 miles per hour (mph) in the vicinity of the site.
Directional flow along Osgood Street is separated by a double yellow centerline to provide two
11-foot wide travel lanes and a 1-foot wide shoulder in each direction. Land uses along Osgood
Street consist of commercial and retail uses.
Traffic Volumes
Base traffic conditions within the study area were developed by conducting automatic traffic
recorder (ATR) counts in July 2012. The ATR counts were collected on Osgood Street adjacent
to the site to obtain daily weekday and Saturday traffic volumes as well as weekday AM,
weekday PM, and Saturday midday peak-hour traffic volumes. All traffic-count data are provided
in the Appendix. Evaluation of the ATR data revealed that weekday AM peak hour occurred
between 8:15-9:15 AM on Tuesday, July 17, 2012; the weekday PM peak hour occurred between
4:45-5:45 PM on Thursday, July 19, 2012; and the Saturday midday occurred between
11:30 AM-12:30 PM on Saturday, July 14, 2012.
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Traffic on a given roadway typically fluctuates throughout the year depending on the area and the
type of roadway. To determine if the traffic counts needed to be adjusted to account for this
fluctuation, traffic-volume data from MassDOT were researched.1 This information revealed that
July traffic volumes are 1.2 percent lower than annual average-month conditions. In addition,
researching the most recent MassDOT Weekday Seasonal Factors revealed that July traffic
volumes are 2.5 percent higher than annual average-month conditions. Therefore, to provide a
conservative (worse-case) analytical framework, the July 2012 traffic data were adjusted upward
by 1.2 percent to represent average-month analysis conditions. The MassDOT seasonal
adjustment data are provided in the Appendix. Table 1 summarizes the existing daily and peak-
hour traffic volumes along Osgood Street adjacent to the site.
Table 1
EXISTING TRAFFIC-VOLUME SUMMARY
Location/Time Period
Daily Volume
(vpd) a
Peak Hour
Volume (vph) b K-Factor c
Directional
Distribution d
Osgood Street adjacent to the site:
Weekday Daily
Weekday AM Peak Hour
Weekday PM Peak Hour
Saturday Daily
Saturday Midday Peak Hour
25,660
18,570
1,837
2,397
1,621
7.2%
9.3%
8.7%
56% SB
60% NB
52% NB
a Vehicles per day. Traffic counts adjusted upward by 1.2 percent to reflect average-month traffic-volume conditions.
b Vehicles per hour. Traffic counts adjusted upward by 1.2 percent to reflect average-month traffic-volume conditions.
c Percent of average daily traffic occurring during the peak hour.
d SB = southbound; NB = northbound.
Collisions
Collision data for the study area were obtained from the North Andover Police Department for
the most recent three-year period available (2009 through 2011). In addition to the crash
summary, collision occurrence was compared to the volume of traffic along a segment of
roadway to determine any significance. Accordingly, the crash rate was calculated for the
segment of roadway between 980 Osgood Street and 1060 Osgood Street and compared with the
statewide average. A segment crash rate is a measure of the frequency of collisions compared to
the volume of traffic along a segment of roadway and is presented in crashes per million vehicle
1 Massachusetts Department of Transportation Highway Division. MassDOT 2009 Traffic Volumes: Permanent
Count Station 5127; Route 125 South of Route 28; Andover, Massachusetts. 2009.
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miles traveled (c/mvmt). The statewide crash rate for an urban principal arterial is 2.62 c/mvmt.
A comparison of the calculated crash rate to the statewide average can be used to establish the
significance of collision occurrence and whether or not potential safety problems exist. The crash
rate worksheet is provided in the Appendix. A summary of the North Andover Police Department
collision data within the study area is provided in Table 2.
Table 2
COLLISION HISTORY SUMMARY
Number of Collisions Severity a Percent During
Location Total
Average
per Year
Crash
Rate b PD PI F
Commuter
Peak c
980-1060 Osgood Street 25 8.3 5.56 15 10 0 48%
Source: North Andover Police Department Data (2009-2011)
a PD = property damage only; PI = personal injury; F = fatality.
b Measured in crashes per million vehicle miles traveled.
c Percent of vehicle incidents that occurred during the weekday AM and weekday PM commuter peak periods.
The North Andover Police Department collision data for this segment of roadway indicates that
25 collisions occurred over the three-year study period where a police officer was dispatched to
the crash location. On average, these incidents equate to 8.3 collisions per year of which the
majority (60 percent) resulted in property damage only. Although the crash rate (5.56 c/mvmt) is
higher than the statewide average for this classification of roadway, not all of the reported
collisions required an incident report. In addition, it should be noted that no collisions were
reported at the existing site driveway (1018 Osgood Street) and 5 of the collisions over the three-
year study period (approximately 1.67 per year) were reported at 1019 Osgood Street. The North
Andover Police Department Incident Daily Press Log did not provide sufficient information to
determine the collision type; therefore, there is not ample information to determine if these
collisions indicate a particular pattern correctable by engineering measures. There were no
reported fatalities along this segment of roadway within the study time period.
Vehicle Speeds
Speed measurements were conducted along Osgood Street in the vicinity of the site by measuring
the elapsed time for vehicles traveling a short, pre-measured distance between two checkpoints.
The travel time was recorded using ATRs and the speed was derived by dividing the elapsed time
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into the measured distance between checkpoints. The results of the speed measurements are
summarized in Table 3.
Table 3
OBSERVED TRAVEL SPEEDS a
Location/Direction
Posted
Speed Limit
Average
Speed
85th Percentile
Speed b
Osgood Street adjacent to the site:
Northbound
Southbound
40
40
36
35
41
40
a In miles per hour (mph).
b Speed at, or below which, 85 percent of all observed vehicles travel.
As shown in Table 3, average travel speeds along Osgood Street adjacent to the site were found
to be between 35 and 36 mph, with 85th percentile speeds of between 40 and 41 mph. The
observed travel speeds along Osgood Street are generally not excessive and are representative of
the roadway classification and alignment.
FUTURE CONDITIONS
To estimate the impact of site-generated traffic within the study area, existing traffic volumes
were projected to the year 2017 which represents a five-year design horizon in accordance with
local and state traffic impact assessment guidelines. The proposed development is expected to be
completed and fully operational well before the 2017 design year. Traffic volumes on the
roadway network at that time will include existing traffic, new traffic due to normal traffic
growth, and traffic related to any significant development by others expected to be completed
within the area by 2017. Consideration of these factors resulted in the development of 2017 No-
Build traffic volumes, which assume that the proposed development is not built. The incremental
impacts of the proposed restaurant development may then be determined by adding site-
generated traffic volumes (Build conditions) and making comparisons to the No-Build
conditions.
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Traffic Growth
To develop the 2017 No-Build forecast volumes, two components of traffic growth were
considered. First, an annual average traffic-growth percentage was determined based on
MassDOT historical traffic-volume data within the Town of North Andover.2 Based on a review
of these data, the MassDOT historical traffic-volume information revealed a 1.5 percent decrease
in traffic since 2000. Such a decline in traffic, however, may not continue. Based on coordination
efforts with Merrimack Valley Planning Commission (MVPC), a background growth rate of
0.5 percent per year was recommended to be representative of future traffic growth in the vicinity
of the site. Therefore, a 0.5 percent compounded annual growth rate was assumed to account for
general population growth and traffic generated by smaller area developments. The MassDOT
data are provided in the Appendix.
Second, any planned or approved specific developments in the area that would generate a
significant volume of traffic on study area roadways within the next five years were included.
Based on discussions with officials from the Town of North Andover, two developments were
identified.
• 1003 Osgood Street – a 19,296 square foot mixed-use development containing retail,
office, and restaurant space will be constructed on the east side of Osgood Street opposite
the proposed Dunkin’ Donuts site. The existing driveways associated with the project will
be closed and access will be provided via a shared driveway with Great Pond Crossing
(1005-1025 Osgood Street). Traffic volumes and methodology associated with the mixed-
use development were obtained from the traffic study and letter prepared for that
development and distributed along the adjacent roadway system.3
• 1077 Osgood Street – a 3,672 square foot branch bank for Pentucket Bank with 2 drive-
through lanes and an Automated Teller Machine lane is proposed within the Butcher Boy
Plaza located north of the proposed Dunkin’ Donuts site. Traffic volumes and
methodology associated with the bank development were obtained from the Institute of
Transportation Engineers (ITE) Trip Generation report for Land Use Code 912 (Drive-In
Bank)4 and based on coordination efforts with the traffic engineer for the project
(BAYSIDE ENGINEERING, INC.) and distributed along the adjacent roadway system.
The trip-generation calculations are provided in the Appendix.
2 Massachusetts Department of Transportation Highway Division. MassDOT 2009 Traffic Volumes: Town of North
Andover along Route 125 and Route 133; 2009.
3 Dermot J. Kelly Associates, Inc. Traffic Impact and Access Study, Proposed Mixed Use Development Project,
1003 Osgood Street, North Andover, Massachusetts. June 24, 2010 and Response to Traffic Peer Review
Comments Letter, September 10, 2010.
4 Trip Generation, 8th Edition: an ITE Informational Report. Washington, DC: Institute of Transportation Engineers,
2008.
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Planned Roadway Improvements
Based on discussions with Town of North Andover officials as well as information provided
from MassDOT, there is one roadway project that is planned to occur through the study area
within the 5-year design horizon. A traffic signal betterment project at 8 locations along
Route 125 in North Andover (MassDOT Project #605730) is expected to begin construction in
the Winter of 2012/2013. The project will install new signal equipment at the Route 125
intersections with Route 133, Sutton Street, Prescott Street, Walker Street, Main Street, and
Massachusetts Avenue. The project will also include a pedestrian crossing south of Village
Green Drive and Peters Street at Andover Street. There were no other roadway improvement
projects identified at the study area intersections that are expected to be constructed within the
design horizon.
No-Build Conditions
The 2017 No-Build traffic volumes were accordingly developed by applying a compounded
0.5 percent annual growth rate (2.5 percent over five years) and by adding the traffic expected to
be generated by the 1003 Osgood Street mixed-use development and the 1077 Osgood Street
drive-in bank development. Table 4 summarizes the No-Build peak-hour traffic volumes along
Osgood Street adjacent to the site.
Table 4
NO-BUILD TRAFFIC-VOLUME SUMMARY
Location/Time Period
Peak Hour
Volume (vph) b
Directional
Distribution d
Osgood Street adjacent to the site:
Weekday AM Peak Hour
Weekday PM Peak Hour
Saturday Midday Peak Hour
1,963
2,580
1,781
55% SB
60% NB
52% NB
a Vehicles per hour.
b SB = southbound; NB = northbound.
Trip Generation
The project site currently contains a vacant residential home and garage. As proposed, the
buildings will be razed and a 2,250 square foot Dunkin’ Donuts with drive-through window will
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be constructed. Traffic to be generated by the proposed development was forecast using the ITE
Trip Generation for Land Use Code 937 (Coffee/Donut Shop with Drive-Through Window). All
trip-generation calculations are provided in the Appendix.
Not all of the vehicle trips expected to be generated by the proposed project represent new trips
on the study area roadway system. Studies have shown that for developments such as the one
proposed, a substantial portion of the site-generated vehicle trips are already present in the
adjacent passing stream of traffic. Based on information published in the ITE Trip Generation
Handbook, the average pass-by trip percentage is 49 percent during the weekday AM peak hour
and 50 percent during the weekday PM peak hour for ITE Land Use Code 934 (Fast-Food
Restaurant with Drive-Through Window).5 Specifically for this project, pass-by trips would be
drawn from Osgood Street. To be consistent with state guidelines for the preparation of traffic
impact studies and to provide a conservative (worse than expected) basis for the analysis,
however, only 25 percent of the site-generated traffic was considered to be pass-by traffic. The
lower percentage of pass-by trips results in more new trips to the study area than expected.
Therefore, the proposed development could have less impact on the adjacent roadway system
than as analyzed due to the higher than expected new trips on the study area roadways beyond the
site driveways. In addition, the proposed Dunkin’ Donuts is being relocated from 982 Osgood
Street which is just two parcels south of the proposed site and on the same side of the roadway.
Therefore, it is expected that most of the projected site-generated traffic already exists on Osgood
Street. Table 5 summarizes the expected trip-generation characteristics of the proposed
redevelopment project.
As shown, the proposed Dunkin’ Donuts development is projected to generate 191 new vehicle
trips (98 entering and 93 exiting) during the weekday AM peak hour, 74 new vehicle trips
(37 entering and 37 exiting) during the weekday PM peak hour, and 146 new vehicle trips
(73 entering and 73 exiting) during the Saturday midday peak hour. It should be noted that the
volume of pass-by traffic does not reduce the total volume of traffic generated by the
development and the total trips generated will still be realized as turning movements at the site
driveways.
5 Hooper, Kevin G. Trip Generation Handbook: An ITE Recommended Practice. Washington, D.C.: Institute of
Transportation Engineers, 2004.
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Table 5
PEAK HOUR TRIP-GENERATION SUMMARY
Time Period/Direction
Proposed
Restaurant Trips a
Pass-By
Trips b
New
Trips c
Weekday AM Peak Hour:
Enter 130 32 98
Exit 125 32 93
Total 255 64 191
Weekday PM Peak Hour:
Enter 49 12 37
Exit 49 12 37
Total 98 24 74
Saturday Midday Peak Hour:
Enter 97 24 73
Exit 97 24 73
Total 194 48 146
a ITE Land Use Code 937 (Coffee/Donut Shop with Drive-Through Window) for 2,300 sf.
b 25 percent of Proposed Restaurant Trips.
c Proposed Restaurant Trips minus Pass-By Trips.
Project Environmental Review (MEPA) Thresholds
The trip generation of the proposed Dunkin’ Donuts redevelopment project was assessed to
determine if the proposed project would meet or exceed any thresholds that would require formal
MEPA environmental review with respect to traffic. One of the thresholds for MEPA
environmental review is the total volume of daily traffic generated by a project. If a proposed
development project requires a state permit and generates a total of more than 2,000 additional
daily vehicle trips, the construction of 300 additional parking spaces, or the combination of
1,000 additional daily vehicle trips and 150 additional parking spaces, then an ENF must be
prepared and filed with the MEPA office. This document must then be subject to both
governmental agency and public review and comment, and the primary government entity
responsible for reviewing the proposed project plans and issuing the permits and approvals that
are required to allow for the construction of the proposed project (in this case, the Town of North
Andover) must take the comments made by other government agencies and the public on these
documents into consideration as part of its decision-making process on the proposed project.
Traffic to be generated by the proposed Dunkin’ Donuts was forecast using the ITE Trip
Generation report for Land Use Code 937 (Coffee/Donut Shop with Drive-Through Window).
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Traffic generated by the existing residential home on the site was estimated based on data
provided in the ITE Trip Generation report for Land Use Code 210 (Single-Family Detached
Housing). All trip-generation data are provided in the Appendix. Based on the existing and
proposed trip generation of the site, the additional daily vehicle trips associated with the
proposed project are summarized in Table 6.
Table 6
DAILY TRIP-GENERATION SUMMARY –
MEPA Transportation Thresholds
Time Period/Direction Existing Trips a Proposed Trips b Additional Trips c
Weekday Daily:
Enter 5 940 935
Exit 5 940 935
Total 10 1,880 1,870
a ITE Land Use Code 210 (Single-Family Detached Housing) for 1 dwelling unit.
b ITE Land Use Code 937 (Coffee/Donut Shop with Drive-Through Window) for 2,300 sf.
c Proposed Trips minus Existing Trips.
As shown in Table 6, the net increase in daily traffic as a result of the proposed project is
estimated to be 1,870 trips. In addition, the proposed Dunkin’ Donuts project will provide
27 parking spaces. Therefore, the project is not expected to exceed the MEPA Transportation
review thresholds set forth in 301 CMR 11.10(6)(b) for the preparation of an ENF.
Drive-Through Lane Vehicle Queuing
The proposed restaurant will provide a drive-through window. The drive-through window lane is
proposed to be 10-feet wide and striped to provide approximately 180 feet of storage. Based on
an average length of vehicle of 20 feet, the drive-through lane provides storage for at least
9 vehicles without impacting on-site circulation. In addition to the striped drive-through window
lane, the site provides approximately 140 additional feet (7 vehicles) of storage on-site without
disrupting flow on Osgood Street. Based on queue data from similar facilities6,7, a queue of
6 Mark Stuecheli, PTP. New Drive-Through Stacking Information for Banks and Coffee Shops. Presented at the
2009 ITE Annual Meeting, August 12, 2009.
7 Mike Spack, PR, PTOE, Max Moreland, EIT, Lindsay de Leeuw, Nate Hood. Drive-Through Queue Generation.
February 2012.
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13 vehicles (260 feet) was noted. Based on the vehicle queue data, it is anticipated that the
vehicle queue for the drive-through window can be accommodated on site.
Site Access
Access to and egress from the site is currently provided via one full-access/egress driveway at the
southern end of the property. As proposed, the existing driveway will be shifted slightly to the
north as well as modified to an exit-only driveway. In addition, a full access/egress driveway is
proposed to be constructed on the northern end of the property.
Site Distribution
Based on transaction data provided by the proponent from other Dunkin’ Donuts locations, on an
average weekday, 28 percent of the customers were revealed to be walk-ins and 72 percent of the
customers utilized the drive-through window. On an average Saturday, 33 percent of the
customers were revealed to be walk-ins and 67 percent utilized the drive-through window. Due to
the proposed layout of the site and the site driveways, it was determined that drive-through
customers would use the south site driveway to exit the site. In addition, it was assumed that
customers who parked in the proposed spaces in the rear of the lot (25 percent) would also use
the south site driveway to exit the site. Accordingly, the estimated exiting site traffic was
assigned to the north and south site driveway.
Although these assumptions were used to distribute the site traffic within the site, it should be
noted that the customer traffic at the site driveways is expected to be self-regulating and vehicles
within the parking area are anticipated to use the driveway with the shorter queue (north
driveway versus south driveway) during peak periods when the driveways may develop longer
queues.
Sight Distance
To identify potential safety concerns associated with site access and egress, sight distances have
been evaluated at the northern and southern site driveway locations to determine if the available
sight distances for vehicles exiting the site meet or exceed the minimum distances required for
approaching vehicles to safely stop. The available sight distances were compared with minimum
requirements, as established by the American Association of State Highway and Transportation
Officials (AASHTO).8 AASHTO is the national standard by which vehicle sight distance is
calculated, measured, and reported. The Massachusetts Executive Office of Transportation and
the Executive Office of Environmental Affairs require the use of AASHTO sight distance
8 A Policy on Geometric Design of Highways and Streets: 2004. Washington, D.C.: American Association of State
Highway and Transportation Officials, 2004.
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standards when preparing traffic impact assessments and studies, as stated in their guidelines for
traffic impact assessments.
Sight distance is the length of roadway ahead that is visible to the driver. The Stopping Sight
Distance (SSD) is the minimum distance required for a vehicle traveling at a certain speed to
safely stop before reaching a stationary object in its path. The SSD is measured from an eye
height of 3.5 feet to an object height of 2 feet above street level, equivalent to the taillight height
of a passenger car. The SSD is measured along the centerline of the traveled way of the major
roadway.
The Intersection Sight Distance (ISD) is provided on minor street approaches to allow the drivers
of stopped vehicles a sufficient view of the major roadway to decide when to enter the major
roadway. By definition, the ISD is the minimum distance required for a motorist exiting a minor
street to turn onto the major street, without being overtaken by an approaching vehicle reducing
its speed from the design speed to 70 percent of the design speed. The ISD is measured from an
eye height of 3.5 feet to an object height of 3.5 feet above street level. The use of an object height
equal to the driver eye height makes ISD reciprocal (i.e., if one driver can see another vehicle,
then the driver of that vehicle can also see the first vehicle).
The SSD is generally more important as it represents the minimum distance required for safe
stopping while the ISD is based only upon acceptable speed reductions to the approaching traffic
stream. The ISD, however, must be equal to or greater than the minimum required SSD in order
to provide safe operations at an intersection. In accordance with the AASHTO manual, “If the
available sight distance for an entering or crossing vehicle is at least equal to the appropriate
stopping sight distance for the major road, then drivers have sufficient sight distance to
anticipate and avoid collisions. However, in some cases, this may require a major-road vehicle
to stop or slow to accommodate the maneuver by a minor-road vehicle. To enhance traffic
operations, intersection sight distances that exceed stopping sight distances are desirable along
the major road.” Accordingly, the ISD should be at least equal to the distance required to allow a
driver approaching the minor roadway to safely stop.
Assuming all the vegetation along the site frontage is removed to accommodate the driveways
and site, the available SSD and ISD at the site driveway locations were measured and compared
to minimum requirements as established by AASHTO. Since the distance required to stop a
vehicle is dependent on the speed of that vehicle, speed studies were conducted as presented in
the Vehicle Speeds section of this memorandum. Based on the posted speed limits within the
study area and the observed speeds along Osgood Street, the SSD and ISD requirements at the
site driveways were calculated. As shown in Table 7, the required minimum sight distances for
each speed are compared to the available distances.
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CONCLUSIONS AND RECOMMENDATIONS
Existing and future conditions in the study area have been described, analyzed, and evaluated
with respect to traffic operations and the impact of the proposed Dunkin’ Donuts. The following
presents conclusions of these efforts and recommendations.
• The site currently contains a residential home and garage. As proposed, the existing
buildings will be razed and a 2,250 square foot Dunkin’ Donuts with a drive-through
window will be constructed. The existing Dunkin’ Donuts located at 982 Osgood Street,
within the Shell gasoline station plaza, will be relocated to 1018 Osgood Street.
• The proposed Dunkin’ Donuts is projected to generate 191 new vehicle trips (98 entering
and 93 exiting) during the weekday AM peak hour, 74 new vehicle trips (37 entering and
37 exiting) during the weekday PM peak hour, and 146 new vehicle trips (73 entering and
73 exiting) during the Saturday midday peak hour. This additional traffic represents an
increase in the range of 36 to 99 vehicles during the peak hours. These increases represent,
on average, 1 additional vehicle every 0.5 to 2 minutes during the peak hours. It should be
noted that these traffic-volume increases beyond the site driveways could be less than as
evaluated due to the lower percentage of pass-by trips used to be consistent with state
guidelines. In addition, the traffic volumes associated with the existing Dunkin’ Donuts
located at 982 Osgood Street are already on the roadway and are expected to shift north to
the proposed site at 1018 Osgood Street.
• Since the site abuts and proposes to have access onto Osgood Street, a state-maintained
roadway, the project is expected to require a State Highway Access Permit from the
MassDOT District 4 office. Based on the net increases in daily traffic and in parking spaces
as a result of the proposed Dunkin’ Donuts project, the MEPA Transportation review
thresholds for the preparation of an ENF are not expected to be exceeded.
• Access to and egress from the site is currently provided via one full-access/egress driveway
at the southern end of the property. As proposed, the existing driveway will be shifted
slightly to the north as well as modified to an exit-only driveway. In addition, a full
access/egress driveway is proposed to be constructed on the northern end of the property. It
is recommended that any proposed landscaping be located sufficiently back from the
driveways and roadway intersections or kept low to the ground so as not to impede the
available sight distances.
• Based on transaction data from other Dunkin’ Donuts locations, on an average weekday,
28 percent of the customers were revealed to be walk-ins and 72 percent of the customers
utilized the drive-through window. On an average Saturday, 33 percent of the customers
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were revealed to be walk-ins and 67 percent utilized the drive-through window. Due to the
proposed layout of the site and the site driveways, it was determined that drive-through
customers would use the south site driveway to exit the site. In addition, it was assumed that
customers who parked in the proposed spaces in the rear of the lot (25 percent) would also
use the south site driveway to exit the site. During peak periods when the driveways may
develop longer queues, however, it is expected that the site driveways will be self-regulating
and vehicles within the parking area are anticipated to use the driveway with the shorter
queue (north driveway versus south driveway).
• The drive-through window lane is 10-feet wide and striped to provide approximately
180 feet of storage. Based on an average length of vehicle of 20 feet, the queue lane provides
storage for at least 9 vehicles without impacting on-site circulation. In addition to the striped
drive-through window lane, the site provides approximately 140 additional feet (7 vehicles)
of storage on-site without disrupting flow on Osgood Street. Based on queue data from
similar facilities, a queue of 13 vehicles (260 feet) was noted. Therefore, it is anticipated that
the vehicle queue for the drive-through window can be accommodated on site.
• Capacity and queue analyses were conducted at the site driveways utilizing Synchro
software and the default values in the program. Due to the high volume of traffic along
Osgood Street, it is expected that motorists typically accept smaller gaps in traffic during
peak periods of traffic than reflected in the analysis model and, therefore, do not wait as long
to exit into the main line of traffic as shown in the analysis results. Therefore, intersection
operating results may be better than as modeled in this memorandum.
• Under 2017 Build traffic conditions, the Osgood Street major street movements at its
intersection with the north site driveway are expected to operate at optimal levels (LOS A)
during the weekday AM, weekday PM, and Saturday midday peak hours. Although the north
site driveway is expected to operate with long delays (LOS F) during the weekday AM and
weekday PM peak hours, the v/c ratios are expected to be well below 1.00 (0.28 or less)
indicating there is ample capacity available with the proposed development in place. Based
on the analyses, delays on the north site driveway are expected to be less than 1 minute and a
±1 vehicle queue is anticipated during the peak hours analyzed. From this, it can be
concluded that the proposed Dunkin’ Donuts development is not expected to have a
significant impact on the operations of Osgood Street.
• Under 2017 Build traffic conditions, the Osgood Street major street movements at its
intersection with the south site driveway are expected to operate at optimal levels (LOS A)
during the weekday AM, weekday PM, and Saturday midday peak hours. The south site
driveway is expected to operate with long delays (LOS F) during the weekday AM and
weekday PM peak hours and at LOS E during the Saturday midday peak hour. The v/c
ratios, however, are expected to be well below 1.00 (0.72 or less) indicating there is ample
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capacity available with the proposed development in place. Vehicle queues are expected to
be ±4 vehicles during the weekday AM peak hour and ±2 vehicles during the weekday PM
and Saturday midday peak hours on the proposed south site driveway. It should be noted that
if motorists accept smaller gaps exiting into the Osgood Street traffic stream than as
modeled, then the analysis results are expected to be better than as presented. In addition, the
analysis model does not account for the nearby traffic signals located on Osgood Street at
Great Pond Road (Route 133) to the north and at Sutton Street to the south. These traffic
signals provide gaps in the traffic stream which allow motorists more opportunity to enter
and exit driveways and curb cuts along Osgood Street. From this, it can be concluded that
the proposed Dunkin’ Donuts development is not expected to have a significant impact on
the operations of Osgood Street.