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TRAFFIC IMPACT AND ACCESS STUDY

PROPOSED MERCEDES-BENZ DEALERSHIP

BURLINGTON, MA

PREPARED FOR:

MERCEDES-BENZ OF BURLINGTON

DECEMBER 9, 2013

PREPARED BY:

600 UNICORN PARK DRIVE WOBURN, MA 01801

TRAFFIC IMPACT AND ACCESS STUDY

PROPOSED MERCEDES-BENZ DEALERSHIP

CAMBRIDGE STREET BURLINGTON, MASSACHUSETTS

Prepared for:

Mercedes-Benz of Burlington

December 9, 2013

Prepared by:

Bayside Engineering 600 Unicorn Park Drive

Woburn, MA 01801

TABLE OF CONTENTS

Section Title Page

1 Executive Summary 1

2 Existing Traffic Conditions 6

Study Area 6 Field Survey 6 Geometrics 6 Traffic Volumes 8 Motor Vehicle Crash Data 13 Public Transportation 15 Sight Distance 16 Planned Roadway Improvements 16

3 Future No-Build and Build Future Conditions 17

Future 2018 No-Build Traffic Volumes 17 Future 2018 Build Conditions 22

4 Capacity Analysis 30

Methodology 30 Analysis Results 32

5 Recommendations and Conclusion 35

Recommendations 35 Conclusion 35

Appendix

TABLES

No. Title Page

1 Existing Weekday Traffic-Volume Summary 9

2 Motor Vehicle Crash Data Summary 14

3 Stopping Sight Distance Summary 16

4 Existing Office Trip Generation Rate Summary 22

5 Proposed Mercedes-Benz Trip Generation Summary 24

6 Proposed Trip Distribution 25

7 Traffic-Volume Increases 29

8 Level-of-Service Criteria for Signalized Intersections 31

9 Level-of-Service Criteria for Unsignalized Intersections 32

10 Signalized Level-of-Service Summary 33

11 Unsignalized Level-of-Service Summary 33

FIGURES

No. Title Page

1 Site Location Map 2

2 2013 Existing Weekday Morning Peak-Hour Traffic Volumes 10

3 2013 Existing Weekday Evening Peak-Hour Traffic Volumes 11

4 2013 Existing Saturday Midday Peak-Hour Traffic Volumes 12

5 2018 No-Build Weekday Morning Peak-Hour Traffic Volumes 19

6 2018 No-Build Weekday Evening Peak-Hour Traffic Volumes 20

7 2018 No-Build Saturday Midday Peak-Hour Traffic Volumes 21

8 2018 Build Weekday Morning Peak-Hour Traffic Volumes 26

9 2018 Build Weekday Evening Peak-Hour Traffic Volumes 27

10 2018 Build Saturday Midday Peak-Hour Traffic Volumes 28

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Q:\Projects\13 PROJECTS\2131722 - THE COLLECTION AUTO GROUP - Mercedes Benz-Burlington\Reports\TIAS 120913 F.docx

SECTION 1: EXECUTIVE SUMMARY

Bayside Engineering has prepared this study to assess the traffic impact and to evaluate the access requirements of the proposed Mercedes-Benz dealership to be located at 80-82 Cambridge Street (Route 3A) in Burlington, Massachusetts. This report identifies existing traffic operating parameters on key roadways and intersections within the study area, evaluates the anticipated traffic volume increases as a result of the proposed project, analyzes the project’s traffic-related impacts, determines the projects access/egress requirements and identifies appropriate mitigating measures designed to minimize the traffic-related impacts created by the project. The following provides a brief summary of the study findings. PROJECT DESCRIPTION The development is to be located on the east side of Cambridge Street, between Burlington Mall Road to the south and Corporate Drive to the north. Currently, the site contains approximately 68,000 square feet (sf) of vacant office space. Access is provided by way of Suburban Lane and a second driveway to the north. As currently proposed, the project will consist of the demolition of the existing buildings and the construction of an approximately 55,000 sf Mercedes-Benz dealership. Parking would be provided for up to 450 vehicles, of which up to 100 would be for customers and employees and the balance of up to 350 spaces as showroom/storage spaces. Access would continue to be provided by way of Suburban Lane and emergency access only at the north site driveway to Cambridge Street. Figure 1 shows the site location in relation to the surrounding area. STUDY METHODOLOGY This study has been prepared in three stages. The first stage involved an assessment of existing conditions within the study area and included an inventory of roadway geometrics, pedestrian and bicycle facilities and public transportation services. Existing traffic counts were performed at the study area intersections.

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In the second stage of the study, future traffic conditions were projected and analyzed. Specific travel demand forecasts for the project were assessed along with future traffic demands due to expected traffic growth independent of the proposed project. In accordance with Massachusetts Department of Transportation (MassDOT) guidelines, the year 2018 was selected as the basis for modeling future transportation impacts of the proposed development to reflect the opening year conditions and a five-year planning horizon. The third stage of the study presents and evaluates measures to address traffic issues, if any, and necessary improvements to accommodate the development.

CAMBRIDGE STREET

Figure 1 Site Location Map

STUDY AREA Roadway geometry and traffic control information was collected for the following locations:

• Cambridge Street at Corporate Drive • Cambridge Street at Arlington Road and existing north site driveway

Butcher Boy Marketplace

Site

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• Cambridge Street at Suburban Lane (existing south site driveway) • Cambridge Street at Burlington Mall Road and Route 128 southbound off-

ramp

EXISTING CONDITIONS Evaluation of existing conditions within the study area includes a description of roadway geometrics, traffic constraints, land uses at the intersections, and quantification of traffic volumes. Existing Traffic Volumes To establish base traffic conditions within the study area, manual turning movement and vehicle classification counts were obtained in August and September 2013. Peak-period turning movement counts were conducted during the weekday morning peak period (7:00 to 9:00 AM), weekday evening period (4:00 to 6:00 PM) and Saturday midday period (10:30 AM to 1:30 PM). Daily traffic counts were conducted on Cambridge Street for a three day period using automatic traffic recorders (ATR). The traffic-volume data gathered as part of this study was collected during the months of August and September 2013. Data from the MassDOT was reviewed to determine the monthly variations of the traffic volumes. Based on the data, August and September volumes are higher than average month volumes. Cambridge Street was recorded to carry approximately 20,900 vehicles per day (vpd). During the weekday morning peak hour, approximately 1,854 vehicles per hour (vph) were recorded and during the weekday evening peak hour, approximately 2,076 vph were recorded. On a Saturday, Cambridge Street was recorded to carry approximately 1,502 vph during the Saturday midday peak hour. Motor Vehicle Crash Data Motor vehicle crash data for the study area intersections and roadways were obtained from the Burlington Police Department for 2009 through 2012, the most recent four-year period for which data is available. A total of 92 crashes were reported. Most of the crashes occurred at the intersection of Cambridge Street and Burlington Mall Road (83 crashes). Most of these crashes did not include full crash reports, just Burlington Police Department incident reports (50 incident reports). A review of these reports indicates that these crashes were minor in nature and did not require the completion of a police report. No fatalities were reported.

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PROBABLE IMPACTS OF THE PROJECT No-Build Traffic Volumes To determine the impact of site-generated traffic volumes on the roadway network under future conditions, baseline traffic volumes in the study area were projected to the year 2018. Traffic volumes on the roadway network at that time, in the absence of the proposed project, would include existing traffic, new traffic due to general background traffic growth, and traffic related to specific developments by others expected to be completed by 2018. A one (1.0) percent compounded growth rate was used to develop future No-Build conditions. Several potential projects were identified and traffic associated with each project was included in the future No-Build projections. Build Traffic Volumes The proposed Mercedes-Benz dealership is expected to generate 302 daily trips (151 vehicles entering and 151 vehicles exiting). During the weekday morning peak hour, 26 vehicle trips (26 vehicles entering and 0 vehicles exiting) are expected and during the weekday evening peak hour, and 1 vehicle trips (1 vehicle entering and 37 vehicles exiting) are expected. During the Saturday midday peak hour, 21 vehicle trips (10 vehicles entering and 11 vehicles exiting) are expected. Two to three car carriers a week are expected to bring vehicles to the site and will be delivered during off-peak hours (between 10:00 AM and 4:00 PM). TRAFFIC OPERATIONS ANALYSIS In order to assess the impacts of the proposed project on the roadway network, traffic operations analyses were performed at the study area intersections under 2013 Existing, 2018 No-Build and 2018 Build conditions. These analyses indicate that the proposed project will not result in a significant impact on traffic operations at the study area intersections over No-Build conditions. RECOMMENDATIONS The capacity analyses performed for the unsignalized intersection along Cambridge Street indicate that overall, the intersections will operate with delays for the critical movements (all movements from the side streets or driveway). At the intersection of Cambridge Street and the proposed site driveway, movements out of the driveway are projected to experience some delay, but this delay and associated queue will occur on site and not on Cambridge Street. It is recommended that the southerly site driveway consist of one entering and one exiting lane and be placed under STOP sign control. The north site driveway should be designed as an emergency access only. Any vegetation or proposed landscaping along Cambridge Street in front of the site

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and within the layout should be cleared and maintained so as to maintain sight distances. Crosswalks and ADA compliant pedestrian ramps should be provided across the site driveway. Internally, crosswalks and sidewalks should be provided to connect the Cambridge Street sidewalks to the internal sidewalk in front of the proposed building. As pedestrians were observed crossing Cambridge Street to access the MBTA bus stop, a crosswalk across Cambridge Street will be explored with MassDOT. SUMMARY The proposed Mercedes-Benz dealership is to be located on the east side of Cambridge Street, north of Burlington Mall Road and south of Corporate Drive. Currently, the site contains approximately 68,000 sf of vacant office space. The site is permitted to allow for a total square footage of 84,500 sf. Based on the traffic generation projections, the proposed Mercedes-Benz of Burlington will generate approximately 75% less traffic than 84,500 sf of office space. Capacity analyses were performed for each of the study area intersections for 2013 Existing, 2018 No-Build (without the Mercedes-Benz dealership) and 2018 Build conditions (with the Mercedes-Benz dealership). Based on the analyses performed, there is no change in level of service from No-Build to Build conditions, with very minor additional delay projected. Recommendations have been made relative to site access and have been geared to provide adequate and safe access to the site for both automobiles and pedestrians. Review of the proposed Mercedes-Benz dealership and access plan shows that in relation to roadway capacity, traffic safety, and traffic impacts upon the surrounding roadway network, the proposed project will meet safety standards and have a minimal impact on existing traffic conditions. With the proposed access, in conjunction with the mitigation measures described above and maintaining sight distances from the driveway (clear sight lines along frontage), safe and efficient access can be provided to the clienteles of the proposed Mercedes-Benz dealership and to the motoring public in the area.

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SECTION 2: EXISTING TRAFFIC CONDITIONS

STUDY AREA Roadway geometry and traffic control information was collected for the following locations:

• Cambridge Street at Corporate Drive • Cambridge Street at Arlington Road and existing north site driveway • Cambridge Street at Suburban Lane (existing south site driveway) • Cambridge Street at Burlington Mall Road and Route 128 southbound off-

ramp FIELD SURVEY A comprehensive field inventory of the proposed site was conducted in August and September 2013. The inventory included collection of existing roadway geometrics, traffic volumes, and safety data for the existing study area intersections and site access driveway locations. Traffic volumes were measured by means of automatic traffic recorder (ATR) counts and substantiated by manual turning movement counts (TMCs) conducted at the study area intersections. GEOMETRICS Primary study area roadways are described below. Roadways Cambridge Street (Route 3A) Cambridge Street is a state numbered and maintained two lane arterial collector which runs in a general north/south direction. In the vicinity of the site, the roadway is approximately 40 to 44 feet wide and provides one lane per direction. Travel lanes are generally separated by a double yellow centerline. The posted speed limit on Cambridge

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Street in the vicinity of the site is 35 miles per hour (mph). Land use along Cambridge Street in the study area consists of a mix of residential, commercial and retail uses. Intersections Cambridge Street and Corporate Drive Cambridge Street forms the north and south legs of this four legged signalized intersection with Corporate Drive (east leg) and a driveway to a small commercial development (west leg). The Cambridge Street approaches each consist of two lanes permitting left- or right-turn movements. The Corporate Drive approach consists of a shared through/left-turn lane and an exclusive right-turn lane. Sidewalks exist along all approaches to the intersection, with a crosswalk across Corporate Drive and the southerly Cambridge Street approach. Land use at the intersection consists of an office building and mixed retail uses. Cambridge Street, Arlington Road and Existing North Site Driveway Cambridge Street forms the north and south legs of this four legged unsignalized intersection with Arlington Road (west leg) and the existing north site driveway. The Cambridge Street approaches each consist of single lanes permitting left- or right-turn movements. The Arlington Road approach consists of a single lane that permits all movements. The site driveway approach consists of a single lane that permits all movements. The Arlington Road approach operates under STOP-sign control. A sidewalk exists along the east side of Cambridge Street. In the northwest and northeast corners of the intersection are two MBTA bus stops. Land use at the intersection consists of mixed retail uses and the proposed site. Cambridge Street and Suburban Lane (Existing South Site Driveway) Cambridge Street forms the north and south legs of this three legged unsignalized intersection with Suburban Lane (east leg). The Cambridge Street approaches each consist of single lanes permitting left- or right-turn movements. The Suburban Lane approach consists of a single lane that permits left- or right-turns. The Suburban Lane approach operates under STOP-sign control. A sidewalk exists along the east side of Cambridge Street. Land use at the intersection consists of commercial uses and the proposed site. Cambridge Street, Burlington Mall Road and Route 128 Southbound Off-ramp Cambridge Street forms the north and south legs of this four legged signalized intersection with Burlington Mall Road (west leg) and Route 128 southbound off-ramp (east leg). The Cambridge Street northbound approach consists of an exclusive left-turn lane and two through lanes. The Cambridge Street southbound approach consists of three through lanes and a channelized right-turn lane. The Burlington Mall Road approach consists of an exclusive left-turn lane and two exclusive right-lanes. The Route

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128 southbound off-ramp approach consists of two through lanes with channelization for right-turns. Sidewalks exist along the east side of Cambridge Street and the north side of Burlington Mall Road. Land use at the intersection consists of office development and wooded land. TRAFFIC VOLUMES Existing Traffic Volumes To establish base traffic conditions within the study area, manual turning movement and vehicle classification counts were obtained in August and September 2013. Peak-period turning movement counts were conducted on Wednesday September 25, 2013 during the weekday morning period (7:00 to 9:00 AM), on Tuesday, August 20 and August 27, 2013 during the weekday evening peak period (4:00 to 6:00 PM) and on Saturday August 17, 2013 during the midday period (12:00 Noon to 2:00 PM) at the following intersections:

• Cambridge Street at Corporate Drive • Cambridge Street at Arlington Road and existing north site driveway • Cambridge Street at Suburban Lane (existing south site driveway) • Cambridge Street at Burlington Mall Road and Route 128 southbound off-

ramp Daily traffic counts were conducted on Cambridge Street for a two day period using automatic traffic recorders (ATR). Analysis of the peak-period traffic counts indicated that the weekday morning commuter peak hour generally occurs between 8:00 and 9:00 AM and the evening commuter peak generally hour occurs between 5:00 and 6:00 PM. The Saturday midday peak hour generally occurs between 12:30 PM and 1:30 PM. The traffic count worksheets are provided in the Appendix. Seasonal Adjustment The traffic-volume data gathered as part of this study was collected during the months of August and September 2013. Data from the MassDOT was reviewed to determine the monthly variations of the traffic volumes. The traffic data showed August and September volumes to be slightly higher than average month conditions. Therefore, the August and September traffic volumes were used to represent average month conditions. The 2013 existing daily and peak-hour traffic volumes for average-month conditions are summarized below in Table 1. The 2013 Existing peak hour traffic flow networks are shown graphically on Figures 2 through 4 for the weekday morning, weekday evening and Saturday midday peak hours. The traffic count worksheets are provided in the Appendix.

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TABLE 1 EXISTING WEEKDAY TRAFFIC-VOLUME SUMMARYa

Weekday

Weekday Morning Peak Hour Weekday Evening Peak Hour

Location Traffic

Volumeb Traffic

Volumec K

Factord Directional

Distributione Traffic Volume

K Factor

Directional Distribution

Cambridge Street, south of Arlington Road

20,900

1,854

6.4

60.9% SB

2,076

7.2

63.0% NB

aTwo-way traffic volume bDaily traffic expressed in vehicles per day. cExpressed in vehicles per hour. dPercent of daily traffic volumes which occurs during the peak hour. ePercent of peak-hour volume in the predominant direction of travel. NB = northbound; SB = southbound; EB = eastbound; WB = westbound.

Cambridge Street carries approximately 20,900 vehicles per day (vpd). During the weekday morning peak hour, approximately 1,854 vehicles per hour (vph) were recorded and during the weekday evening peak hour, approximately 2,076 vph were recorded. On a Saturday, Cambridge Street was recorded to carry approximately 1,502 vph during the Saturday midday peak hour.

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MOTOR VEHICLE CRASH DATA Motor vehicle crash data for the study area intersections and roadways were obtained from the Burlington Police Department for 2009 through 2012, the most recent four-year period for which data is available. The motor vehicle crash data was reviewed to deter-mine crash trends in the study area. Ninety-two (92) crashes were reported during the four year interval. The crash data is summarized in Table 2.

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TABLE 2 MOTOR VEHICLE CRASH DATA SUMMARYa

Location

Scenario

Cambridge

Street at Corporate

Drive

Cambridge

Street at Arlington

Road

Cambridge Street at

Suburban Lane

Cambridge Street at

Burlington Mall Road and Route 128

Southbound Off-ramp Year: 2009 2010 2011 2012 Total

0 0 1

3 6

1 0 0

0 1

0 0 2

0 2

26 18 22

17 83

Averageb

1.5

0.3

0.5

20.8

Crash Ratec

0.14

0.02

0.05

1.03

Significantd

No

No

No

Yes

Type: Angle Rear-End Head-On Sideswipe Single Vehicle Crash Hit Fixed Object Unknown Total

2 1 0 1 0 0

2 6

0 0 0 1 0 0

0 1

0 1 0 0 0 0

1 2

10 13 2 5 2 1

50 83

Time of Day: Weekday (7:00 to 9:00 AM) Weekday (4:00 to 6:00 PM) Remainder of Day Unknown Total

4 1 0

1 6

0 0 1

0 1

0 1 1

0 2

7 14 60 2 83

Pavement Conditions: Dry Wet Snow Unknown Total

2 1 0

3 6

0 0 0

1 1

1 0 0

1 2

25 2 3

53 83

Severity: Property Damage Only Personal Injury Fatal Accident Unknown Total

4 1 0

1 6

1 0 0

0 1

2 0 0

0 2

63 8 0

12 83

aSource: Burlington Police Department records, 2009 through 2012. bAverage crashes over three-year period. cCrash rate per million entering vehicles (mev). dSignalized intersections are significant if rate >0.78 crashes per million vehicles, and unsignalized intersections are significant if rate >0.59

crashes per million vehicles.

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Most of the crashes occurred at the intersection of Cambridge Street and Burlington Mall Road (83 crashes). Most of these crashes did not include full crash reports, just Burlington Police Department incident reports (50 incident reports). A review of these reports indicates that the crashes were minor in nature and did not require the completion of a police report. No fatalities were reported. The crash worksheets are included in the Appendix PUBLIC TRANSPORTATION Public transportation within the study area is provided by the Massachusetts Bay Transportation Authority (MBTA) and the Lowell Regional Transit Authority (LRTA). There are currently two MBTA bus routes (Bus Routes #350 and #351) and two localized Bus routes (Burlington “B”) that traverse through the study area or through study area intersections. Bus route and schedule data are included in Appendix A and a summary of the route data is provided below:

• MBTA Route 350–North Burlington to Alewife Station Service is provided along Cambridge Street (Route 3A), the Middlesex Turnpike, Burlington Mall Road in Burlington; along Cambridge Street (US 3) in Woburn, along Mystic Street (US 3), and Massachusetts Avenue (US 3/Route 2A) in Arlington, and at Alewife Station in Cambridge. This bus operates from roughly 6:13 AM to 11:05 PM on weekdays with approximately 10-60 minute headways and from roughly 7:10 AM to 11:05 PM on weekends with approximately 40-60 minute headways.

• MBTA Route 351–Oak Park/Bedford Woods to Alewife Station Service is

provided along the Middlesex Turnpike, Crosby Drive, Burlington Road (Route 62) and Network Drive in Bedford, along Network Drive, the Middlesex Turnpike, Fourth Avenue, Third Avenue, Second Avenue, and Burlington Mall Road in Burlington, and along Alewife Station Access Road and Alewife Station in Cambridge. This bus operates from roughly 3:20 PM to 7:05 PM inbound and 6:15 AM to 9:35 AM outbound on weekdays with approximately 50-60 minute headways.

• Burlington Public Transportation Route 10/10R–Beacon Street to Malls Service is provided along Center Street, Birchcrest Street, Cambridge Street (Route 3A), Wayside Road, South Bedford Street, Blanchard Road, Wheeler Road, Old Concord Road, Middlesex Turnpike, Burlington Mall Road, Great Meadows Road, A Street, Terrace Hall Avenue, Bedford Street, Winn Street Beacon Street, Pearl Street, and Peach Orchard Road in Burlington. This bus operates twice a day leaving Center Street at 4:00 PM and 5:00 PM for an hour long route.

• Burlington Public Transportation Route 12/12R–Beacon Street to Malls

Service is provided along Center Street, Cambridge Street (Route 3A),

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Fox Hill Road, Wilmington Road, Bedford Street, Terrace Hall Avenue, Middlesex Turnpike, Burlington Mall Road, to Cambridge Street in Burlington. This bus operates twice a day leaving Center Street at 8:00 AM and 9:00 AM and 4:30 PM and 5:30 PM for an hour long route.

SIGHT DISTANCE Sight distance measurements were performed at the intersections of the site driveways in accordance with Massachusetts Department of Transportation (MassDOT) standards. Stopping sight distance (SSD) measurements were performed. In brief, SSD is the dis-tance required by a vehicle traveling at the design speed of a roadway, on wet pavement, to stop prior to striking an object in its travel path. Intersection sight distance (ISD) or corner sight distance (CSD) is the sight distance required by a driver entering or crossing an intersecting roadway, to perceive an on-coming vehicle and safely complete a turning or crossing maneuver with on-coming traffic. Table 3 presents the measured SSD at the intersection of the proposed site driveway at Cambridge Street. TABLE 3 STOPPING SIGHT DISTANCE SUMMARY Required

Minimum (Feet)a

Measured (Feet)

Cambridge Street and Site Driveway (Suburban Lane) Stopping Sight Distance: Cambridge Street approaching from the north Cambridge Street approaching from the south

288 288

300 400

aRecommended minimum values obtained from A Policy on Geometric Design of Highways and Streets; American Association of State

Highway and Transportation Officials (AASHTO); 2010, and based on a 40 mph 85th percentile speed adjusted for grade. As can be seen in Table 3, the SSD measurements performed at the proposed site driveway intersection with Cambridge Street indicate that the intersection exceeds the recommended minimum requirements based on an 85th percentile speed of 40 mph1. At the Cambridge Street and site driveway intersection, along the site frontage and within the existing Cambridge Street layout, it is recommended that any proposed landscaping be less than three (3) feet in height and maintained for sight lines. PLANNED ROADWAY IMPROVEMENTS Officials for the City of Burlington were contacted regarding roadway improvements planned for the study area intersections. No improvements are currently planned.

1Based on speed data collected by ATR from August 2013 and speed measurements by radar on Cambridge Street.

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SECTION 3: FUTURE NO-BUILD AND BUILD TRAFFIC CONDITIONS

To determine the impact of site-generated traffic volumes on the roadway network under future conditions, baseline traffic volumes in the study area were projected to the year 2018. Traffic volumes on the roadway network at that time, in the absence of the proposed project, would include existing traffic, new traffic due to general background traffic growth, and traffic related to specific developments by others expected to be completed by 2018. Consideration of these factors resulted in the development of 2018 No-Build traffic volumes. Anticipated site-generated traffic volumes were then superimposed upon these No-Build traffic flow networks to develop the 2018 Build conditions. FUTURE 2018 NO-BUILD TRAFFIC VOLUMES Traffic growth on area roadways is a function of the expected land development in the immediate area as well as the surrounding region. Several methods can be used to estimate this growth. A procedure frequently employed estimates an annual percentage increase in traffic growth and applies that percentage to all traffic volumes under study. The drawback to such a procedure is that some turning volumes may actually grow at either a higher or a lower rate at particular intersections. An alternative procedure identifies the location and type of planned development, estimates the traffic to be generated, and assigns it to the area roadway network. This produces a more realistic estimate of growth for local traffic. However, the drawback of this procedure is that the potential growth in population and development external to the study area would not be accounted for in the traffic projections. To provide a conservative analysis framework, both procedures were used.

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Background Traffic Growth Traffic-volume data compiled by MassDOT from permanent count stations and historic traffic counts in the area were reviewed in order to determine traffic growth trends. Based on a review of this data, it was determined that traffic volumes within the study area have shown little growth or generally decreased over the past several years. Therefore, to provide a conservative growth estimate, a one (1.0) percent per year compounded annual background traffic growth rate was used to account for potential future traffic growth external to the study area and presently unforeseen development. The MassDOT data is contained in the Appendix. Specific Development by Others Traffic volumes generated by the specific local developments by others were included in the 2018 No-Build condition. The Town of Burlington was contacted to identify specific planned developments. Based on these discussions, there are several potential projects that are currently underway. These include:

• Middlesex Marketplace – 90 Middlesex Turnpike; Approximately 38,880 sf of retail space

• Sun Microsystems – Route 62/Network Drive; 151,000 sf office remaining, 126,000 sf office vacant, 8,000 sf retail, 350 seat restaurant

• The Summit – 400 Wheeler Road; 250,000 sf office • Oracle – Phase III – Van de Graffe Drive; 101,000 sf office remaining • Arborpoint at Burlington – Seven Springs Lane; 15 residential units

remaining • Lahey Clinic Expansion – Burlington Mall Road; 150,000 sf hospital

space remaining • 78 Blanchard Road – 78 Blanchard Road; 120,000 sf office • Marriott Extended Stay Hotel – Burlington Mall Road; 139 Room Hotel • Northwest Park – Middlesex Turnpike; 140,000 sf Supermarket, 160,000

sf retail, 200 apartments • Burlington Research Center – 43/63 South Avenue; 590,000 sf of R&D

space Trips for each project was obtained from the studies performed or based on trip generation data compiled by the ITE in Trip Generation. No-Build Condition Traffic Volumes The 2018 No-Build weekday morning, weekday evening and Saturday midday peak-hour traffic volumes were developed by applying a compounded one percent annual growth rate to the 2013 Existing peak-hour traffic volumes and adding traffic from the identified background projects. Figures 5 through 7 show the projected 2018 No-Build peak hour traffic volumes for the respective weekday morning, weekday evening and Saturday midday peak-hour conditions.

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FUTURE 2018 BUILD CONDITIONS Project Description As currently proposed, the project will consist of the demolition of the existing buildings and the construction of an approximately 55,000 sf Mercedes-Benz dealership. Parking would be provided for up to 450 vehicles, of which 100 would be for customers and employees and the balance of 350 spaces as showroom/storage spaces. Access would continue to be provided by way of Suburban Lane and emergency access only at the north site driveway to Cambridge Street. Existing Site Traffic Generation Currently the site comprises two office buildings totaling approximately 68,000 sf of space. The site is currently permitted to allow the expansion to approximately 84,500 sf without any additional permitting. Summarized in Table 4 is the expected traffic generation utilizing trip-generation data published by the Institute of Transportation Engineers (ITE) Trip Generation manual2 for Land Use Code (LUC) 710 – General Office.

TABLE 4 EXISTING OFFICE TRIP-GENERATION SUMMARY

Office Tripsa

Average Weekday Daily Traffic

1,156b

Weekday Morning Peak Hour: Entering Exiting Total

147 20 167

Weekday Evening Peak Hour: Entering Exiting Total

29 144 173

Saturday Daily Traffic

200

Saturday Midday Peak Hour: Entering Exiting Total

19 17 36

aBased on ITE LUC 710, General Office; 84,500 sf. bIncludes trucks estimated at 9+ trucks per day.

2Trip Generation, Ninth Edition; Institute of Transportation Engineers; Washington, DC; 2012.

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Proposed Site Traffic Generation Site generated traffic was initially based on trip-generation data published by the ITE Trip Generation manual3. Data has been collected by ITE over the past decades for automobile dealerships. However, this data is not reflective of the proposed Mercedes-Benz dealership. With Mercedes-Benz, luxury car buyers tend to visit fewer dealerships than non-luxury automobile buyers. Most of the buying actually happens over the phone/email. Additionally, approximately 25 percent of test drives and service visits occur where the vehicle is taken to the client’s home or office for the test drive or service call. Mercedes-Benz will employ approximately 65 employees in Burlington. Of the 65 employees, 30 will be mechanics who arrive by 7:00 AM and depart at 6:00 PM. Twenty (20) employees will be sales and administrative support who will arrive by 9:00 AM and depart at 8:00 PM. The remaining 15 employees will be in support roles and will come and go throughout the day. Delivery of automobiles to the site by car carrier will occur two to three times a week. The driveways and site have been designed such that the unloading of the car carrier will occur on the site in the rear of the facility and not on Cambridge Street. Once a day, after closing, a parts truck will arrive to deliver parts for repairs. Trash pick-up is expected to occur two or three times per week during non-peak commuter hours. Table 5 summarizes the expected project traffic generation. The proposed Mercedes-Benz dealership is expected to generate 302 daily trips (151 vehicles entering and 151 vehicles exiting). During the weekday morning peak hour, 26 vehicle trips (26 vehicles entering and 0 vehicles exiting) are expected and during the weekday evening peak hour, and 1 vehicle trips (1 vehicle entering and 37 vehicles exiting) are expected. During the Saturday midday peak hour, 21 vehicle trips (10 vehicles entering and 11 vehicles exiting) are expected.

3Trip Generation, Ninth Edition; Institute of Transportation Engineers; Washington, DC; 2012.

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TABLE 5 PROPOSED MERCEDES-BENZ TRIP-GENERATION SUMMARY

Mercedes-Benz Tripsa

Average Weekday Daily Traffic

302b

Weekday Morning Peak Hour: Entering Exiting Total

26 0 26

Weekday Evening Peak Hour: Entering Exiting Total

1 37 38

Saturday Daily Traffic

302

Saturday Midday Peak Hour: Entering Exiting Total

11 10 21

aBased on proposed dealership characteristics and operations. bCar Carriers are two to three trucks per week.

Trip Distribution The directional distribution of the vehicular traffic approaching and departing the site is a function of population densities, the location of employment, existing travel patterns, similar uses, and the efficiency of the existing roadway system. Table 6 summarizes the expected trip distribution.

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TABLE 6 PROPOSED TRIP DISTRIBUTION

TOTAL 100

Future Traffic Volumes - Build Condition The site-generated traffic was distributed within the study area according to the percentages summarized in Table 6. The site generated volumes were superimposed onto the 2018 No-Build traffic volumes to represent the 2018 Build traffic-volume conditions. The anticipated 2018 Build weekday morning, weekday evening and Saturday midday traffic volumes are graphically presented in Figures 8 through 10. These volumes were used as the basis for all analysis as well as to identify potential mitigation measures to ameliorate the project’s impacts.

Route

Direction

Percent of Trips

Route 128 southbound Off-ramp

East

30

Burlington Mall Road

West

10

Cambridge Street Cambridge Street

North

South

20

40

29


A summary of 2018 peak-hour projected traffic-volume changes in the site vicinity are shown in Table 7. These volumes are based on the expected increases from the site traffic generation.

TABLE 7 TRAFFIC-VOLUME INCREASESa

Location/Peak Hour 2018

No-Build 2018 Build

Volume Increase

over No-Build

Percent Increase

over No-Build

Cambridge Street, north of Corporate Drive Weekday Morning Weekday Evening Saturday Midday

1,781 2,115 1,505

1,786 2,122 1,509

5 7 4

0.3 0.3 0.3

Cambridge Street, south of Burlington Mall Road Weekday Morning Weekday Evening Saturday Midday

2,038 3,272 1,962

2,048 3,299 1,974

10 27 12

0.5 0.8 0.6

Burlington Mall Road, west of Cambridge Street Weekday Morning Weekday Evening Saturday Midday

2,336 2,864 1,577

2,339 2,868 1,579

3 4 2

0.1 0.1 0.1

aAll volumes are vehicles per hour, total of both directions. As shown in Table 7, project-related increases are in the range of 3 to 10 bi-directional vehicles during the weekday morning peak hour, 4 to 27 bi-directional vehicles during the evening peak hour and approximately 2 to 12 bi-directional vehicles during the Saturday midday peak hour on Cambridge Street. As shown in Table 7, this represents a less than one percent increase in traffic outside the study area.

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SECTION 4: CAPACITY ANALYSIS

To assess intersection operations, capacity analyses were conducted for Existing, No-Build, and Build traffic-volume conditions. Capacity analyses provide an indication of how well the study area intersections serve existing and projected traffic volumes. Vehicle queue analyses provide a secondary measure of the operational characteristics of an intersection or section of roadway under study in terms of lane use and demand. METHODOLOGY Levels of Service Level of service (LOS) is a quantitative measure used to describe the operation of an intersection or roadway segment. The level of service definition is described by the quality of traffic flow and is primarily defined in terms of traffic delays. The primary result of capacity analyses4 is the assignment of a level of service to traffic intersections or roadway segments under various traffic-flow conditions. Six levels of service are defined for traffic intersections and roadway segments. Levels of service range from LOS A to LOS F. LOS A represents very good operating conditions and LOS F represents very poor operating conditions. Signalized Intersections Levels of service for signalized intersections are calculated using the methodology and procedures described in the 2010 Highway Capacity Manual. The methodology assesses the intersection based on type of signal operation, signal timing and phasing, progression, vehicle mix, and intersection geometrics. Level-of-service designations are based on the delay per vehicle. Table 8 summarizes the relationship between level of service and delay. The calculated delay values result in level-of-service designations which are applied to individual lane groups, to individual intersection approaches, and to the entire intersection.

4The capacity analysis methodology is based on procedures presented in the Highway Capacity Manual; Transportation

Research Board; Washington, DC; 2010.

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TABLE 8 LEVEL-OF-SERVICE CRITERIA FOR SIGNALIZED INTERSECTIONSa

Delay per Vehicle

(Seconds) Resulting

Level of Service

<10.0 10.1 to 20.0 20.1 to 35.0 35.1 to 55.0 55.1 to 80.0

>80.0

A B C D E F

aHighway Capacity Manual; Transportation Research Board; Washington, DC; 2010; page 18-6.

Unsignalized Intersections The level of service for an unsignalized intersection is determined by the methodology and procedures described in the 2000 Highway Capacity Manual.5 The level of service for unsignalized intersections is measured in terms of average delay for the critical movements (typically side street turning movements or mainline turning movements). The delay for the critical movements is a function of the available capacity for the movement and the degree of saturation of the lane group containing the critical movement. The delay calculation includes the effects of initial deceleration delay approaching a STOP sign, stopped delay, queue move-up time, and final acceleration delay from a stopped condition. The definitions for level of service at unsignalized intersections are also provided in the 2010 Highway Capacity Manual. Table 9 summarizes the relationship between level of service and average control delay for the critical movements at unsignalized intersections.

5Highway Capacity Manual; Transportation Research Board; Washington, DC; 2010.

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TABLE 9 LEVEL-OF-SERVICE CRITERIA FOR UNSIGNALIZED INTERSECTIONSa

Average Delay

(seconds per vehicle) Resulting

Level of Service

< 10.0 10.1 to 15.0 15.1 to 25.0 25.1 to 35.0 35.1 to 50.0

>50.0

A B C D E F

aHighway Capacity Manual; Transportation Research Board; Washington, DC; 2010; page 19-2

The analytical methodologies used for the analysis of unsignalized intersections use conservative analysis parameters, such as high critical gaps. The critical gap is defined as the minimum time between successive main line vehicles for a side street vehicle to execute the appropriate turning maneuver. Actual field observations indicate that drivers on minor streets accept smaller gaps in traffic than those used in the analysis procedures and therefore experience less delay than calculated by the HCM methodology. The analysis results overstate the actual delays experienced in the field. It should be noted that the unsignalized intersections along heavily trafficked roadways operate at constrained levels and the resulting calculated results of the unsignalized intersection analyses should be considered highly conservative. ANALYSIS RESULTS Level-of-service analyses were conducted for 2013 Existing, 2018 No-Build, and 2018 Build conditions for the intersections within the study area. The results of the 2018 signalized analyses are summarized in Table 10 and the 2018 unsignalized analyses are summarized in Table 11. Detailed analysis sheets are presented in the Appendix. Cambridge Street, Burlington Mall Road and Route 128 Southbound Off-Ramp Under 2013 Existing weekday morning conditions, this signalized intersection currently operates at level of service (LOS) D during the weekday morning peak hour, at LOS D during the weekday evening peak hour and at LOS C during the Saturday midday peak hour. Under future 2018 No-Build conditions, this intersection is projected to operate at LOS E during the weekday morning peak and at LOS E during the weekday evening peak hour and at LOS C during the Saturday midday peak hour. Under 2018 Build conditions, with the project, the intersection is projected to continue to operate at LOS E during the weekday morning peak hour, at LOS E during the weekday evening peak hour

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and at LOS C during the Saturday midday peak hour.

TABLE 10 SIGNALIZED LEVEL-OF-SERVICE ANALYSIS SUMMARY

Signalized Intersection/

2013 Existing

2018 No-Build

2018 Build

Peak Hour/Lane Group V/Ca Delayb LOSc V/C Delay LOS V/C Delay LOS Cambridge Street, Burlington Mall Road and Route 128 Southbound Off-Ramp Weekday Morning Weekday Evening Saturday Midday

0.94 0.83 0.56

42.2 40.2 25.2

D D C

1.09 0.98 0.70

65.2 61.2 28.8

E E C

1.10 0.99 0.70

65.4 61.1 28.8

E E C

Cambridge Street and Corporate Drive Weekday Morning Weekday Evening Saturday Midday

0.55 0.66 0.28

4.5

11.2 2.3

A B A

0.76 0.84 0.34

7.1

17.2 3.4

A B A

0.76 0.84 0.34

7.1

17.2 3.4

A B A

aVolume-to-capacity ratio. bDelay in seconds per vehicle. cLevel of service.

TABLE 11 UNSIGNALIZED LEVEL-OF-SERVICE ANALYSIS SUMMARY

2013 Baseline

2018 No-Build

2018 Build Critical Movement/

Peak Hour

Demanda

V/Cb

Delayc

LOSd

Demand

V/C

Delay

LOS

Demand

V/C

Delay

LOS Cambridge Street, Arlington Road and North Site Driveway

All movements from driveway: Weekday Morning Weekday Evening Saturday Midday

4 5 9

0.10 0.09 0.11

28.8 48.8 23.3

D E C

4 5 9

0.15 0.15 0.14

43.6 82.8 28.9

E F D

0 0 0

0.00 0.00 0.00

0.00 0.00 0.00

--e

-- --

All movements from Arlington Road: Weekday Morning Weekday Evening Saturday Midday

19 20 18

0.21 0.22 0.13

37.3 32.7 22.2

E D C

20 21 19

0.32 0.37 0.17

58.4 59.5 26.9

F F D

20 21 19

0.29 0.37 0.17

50.5 59.5 26.5

F F D

Cambridge Street and Suburban Lane

All movements from driveway: Weekday Morning Weekday Evening Saturday Midday

4 3 1

0.12 0.16 0.02

45.0 63.8 26.8

E F D

4 3 1

0.18 0.24 0.03

71.4 98.4 32.7

F F D

1

30 10

0.02 0.67 0.07

63.1 144.4 30.0

F F D

aDemand of critical movements in vehicles per hour. bVolume-to-capacity ratio. cDelay in seconds per vehicle. dLevel of service. eDriveway closed. For emergency access only.

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Cambridge Street and Arlington Road Under 2013 existing conditions, during the weekday morning peak hour, the critical movements (all movements from Arlington Road) are projected to operate at LOS E during the weekday morning peak hour, at LOS D during the weekday evening peak hour and at LOS C during the Saturday midday peak hour. Under future 2018 No-Build conditions, these critical movements are projected to operate at LOS F during the weekday morning peak hour, at LOS F during the weekday evening peak hour and at LOS D during the Saturday midday peak hour. Under future 2018 Build conditions, with the project, these critical movements are projected to operate at LOS F during the weekday morning peak hour, at LOS F during the weekday evening peak hour and at LOS D during the Saturday midday peak hour. Based on existing intersection operations and observations, actual operations will be better than the HCS methodology indicates. Cambridge Street and Suburban Lane Under 2013 existing conditions, during the weekday morning peak hour, the critical movements (all movements from Suburban Lane) are projected to operate at LOS E during the weekday morning peak hour, at LOS F during the weekday evening peak hour and at LOS D during the Saturday midday peak hour. Under future 2018 No-Build conditions, these critical movements are projected to operate at LOS F during the weekday morning peak hour, at LOS F during the weekday evening peak hour and at LOS D during the Saturday midday peak hour. Under future 2018 Build conditions, with the project, these critical movements are projected to operate at LOS F during the weekday morning peak hour, at LOS F during the weekday evening peak hour and at LOS D during the Saturday midday peak hour. Based on existing intersection operations and observations, actual operations will be better than the HCS methodology indicates. Cambridge Street and Corporate Drive Under 2013 Existing weekday morning conditions, this signalized intersection currently operates at LOS A during the weekday morning peak hour, at LOS B during the weekday evening peak hour and at LOS A during the Saturday midday peak hour. Under future 2018 No-Build conditions, this intersection is projected to operate at LOS A during the weekday morning peak and at LOS B during the weekday evening peak hour and at LOS A during the Saturday midday peak hour. Under 2018 Build conditions, with the project, the intersection is projected to continue to operate at LOS A during the weekday morning peak hour, at LOS B during the weekday evening peak hour and at LOS A during the Saturday midday peak hour.

.

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SECTION 5: RECOMMENDATIONS AND CONCLUSION

RECOMMENDATIONS The final phase of the analysis process is to identify the mitigation measures necessary to minimize the impact of the project on the transportation system. The proponent has made a commitment to implement the mitigation measures listed below. The capacity analyses performed for the unsignalized intersection along Cambridge Street indicate that overall, the intersections will operate with delays for the critical movements (all movements from the side streets or driveway). At the intersection of Cambridge Street and the proposed site driveway, movements out of the driveway are projected to experience some delay, but this delay and associated queue will occur on site and not on Cambridge Street. It is recommended that the southerly site driveway consist of one entering and one exiting lane and be placed under STOP sign control. The north site driveway should be designed as an emergency access only. Any vegetation or proposed landscaping along Cambridge Street in front of the site and within the layout should be cleared and maintained so as to maintain sight distances. Crosswalks and ADA compliant pedestrian ramps should be provided across the site driveway. Internally, crosswalks and sidewalks should be provided to connect the Cambridge Street sidewalks to the internal sidewalk in front of the proposed building. As pedestrians were observed crossing Cambridge Street to access the MBTA bus stop, a crosswalk across Cambridge Street will be explored with MassDOT. CONCLUSION The proposed Mercedes-Benz dealership is to be located on the east side of Cambridge Street, north of Burlington Mall Road and south of Corporate Drive. Currently, the site contains approximately 68,000 sf of vacant office space. The site is permitted to allow for a total square footage of 84,500 sf. Based on the traffic generation projections, the

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proposed Mercedes-Benz of Burlington will generate approximately 75% less traffic than 84,500 sf of office space. Capacity analyses were performed for each of the study area intersections for 2013 Existing, 2018 No-Build (without the Mercedes-Benz dealership) and 2018 Build conditions (with the Mercedes-Benz dealership). Based on the analyses performed, there is no change in level of service from No-Build to Build conditions, with very minor additional delay projected. Recommendations have been made relative to site access and have been geared to provide adequate and safe access to the site for both automobiles and pedestrians. Review of the proposed Mercedes-Benz dealership and access plan shows that in relation to roadway capacity, traffic safety, and traffic impacts upon the surrounding roadway network, the proposed project will meet safety standards and have a minimal impact on existing traffic conditions. With the proposed access, in conjunction with the mitigation measures described above and maintaining sight distances from the driveway (clear sight lines along frontage), safe and efficient access can be provided to the clienteles of the proposed Mercedes-Benz dealership and to the motoring public in the area.

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