STUDY DESCRIPTION MEMORANDUM. DATE April 20, 2011

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Kelley Roberts
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1 DATE April 0, 0 TO FROM RE MEMORANDUM Congestion Management Program Files Ariel Godwin, CMP Manager Boston Region MPO Staff Limited-Access Highway Counts and Traffic Volumes, Summer 00 This memorandum presents the results of summer 00 vehicle occupancy counts. occupancy count data are collected as part of the Congestion Management Process (CMP) work program. The CMP is an ongoing multimodal MPO program that has been funded (formerly under various other names) by the Boston Region MPO since 995. The CMP s tasks include collecting performance data about the region s transportation system, identifying causes of recurring congestion, and developing recommendations for congestion-reducing strategies that can be implemented through projects funded in the MPO s Transportation Improvement Program (TIP). In addition, the CMP supports the MPO s Long-Range Transportation Plan (LRTP) by providing data for needs assessment and recommending strategies for the LRTP. Data collected as part of the CMP can also be used for transportation modeling. STUDY DESCRIPTION In the fiscal year 0 Unified Planning Work Program (UPWP), the CMP work program was updated to include monitoring of vehicle occupancies. The purpose of this monitoring is to provide data for future HOV system planning and other transportationdemand-management work. The vehicle occupancy counts from general-purpose lanes described in this memo may be particularly useful for HOV system planning. Currently the freeway sections in which data were collected do not have HOV lanes. occupancy data collection took place between June 5 and July 7, 00, at seven locations:. Route, northbound, between exits 5 and 6 in Weymouth. Route northbound near the I-9 ramps in Randolph. Route southbound near the I-9 ramps in Randolph. I-90 eastbound between exits and in Natick 5. I-95, northbound, between exits 0A and 0B in Lexington 6. I-9, northbound, between exits and in Wilmington

2 Boston Region MPO April 0, 0 7. I-9, southbound, between exits and in Wilmington Data collection took place in the morning (7:00 9:00 AM) for inbound traffic (in the direction of downtown Boston) and in the afternoons (:00 6:00 PM) for outbound traffic. Data were collected by MPO staff; each staff member monitored one lane and recorded the number of occupants in each vehicle that passed using a mechanical tally counting board. Data collection presented some challenges. In particular, a visual assessment of how many people are in a passing vehicle can be challenging depending on factors such as lighting conditions, vehicle speed, and vehicle window tinting. Also, given the limitedaccess design of freeways and the high speed of traffic, it was difficult to find a safe location, with clear lines of sight, from which to collect data. The safety of the data collectors was a significant factor in the choice of locations. To this end, rest stop locations were sought for observers to park their vehicles and also have a clear sight distance. For four of the seven locations at which data were collected, a MassDOT van was required in order to assure adequate safety. Assumptions Because of the difficulty, or in some cases impossibility, of counting the number of occupants inside certain types of vehicles, the following assumptions were made when calculating the average vehicle occupancy numbers: in the category were assumed to have an occupancy of 5.5. es were assumed to have an occupancy of 0. es were assumed to have an occupancy of 5. Police, fire, and vehicles were assumed to have an occupancy of. in the Known category were assumed to have an occupancy of. This includes limousines and other vehicles with blacked-out windows and vehicles for which visibility did not permit an accurate count. These assumptions were developed by staff. Although they are not necessarily specific to the locations, it was not possible to develop any more location-specific assumptions for these particular vehicle types. RESULTS BY LOCATION Figure shows the count locations, as well as the locations of the HOV lanes. Locations are in geographical order clockwise from southeast to north.

3 Boston Region MPO April 0, 0 Route Northbound Table shows summer 00 vehicle occupancy data for Route northbound, between exits 5 and 6 in Weymouth. Data were collected on June 5, between 7:00 AM and 9:00 AM. At this location, there are two general-purpose lanes and one breakdown lane, which is used for general-purpose traffic from 6:00 AM to 0:00 AM. The hourly volumes ranged between,706 and,59 vehicles, totaling 5,965 vehicles during the two-hour period. The occupancy rate for each lane was. persons per vehicle. Approximately 7,79 persons in 5,965 vehicles were counted. Route Northbound Table shows summer 00 vehicle occupancy data for Route, at the construction site near the I-9 ramps in Randolph, in the northbound direction. Data were collected on July 7, between 7:00 AM and 9:00 AM. There are three general-purpose lanes at this location. The hourly volumes ranged from,8 to,7 vehicles, totaling 9, vehicles during the two-hour period. The average vehicle occupancy across all three lanes was. persons per vehicle. Approximately,8 persons in 9, vehicles were counted. A MassDOT van was needed for safe data collection at this location. Route Southbound Table shows summer 00 vehicle occupancy data for Route, at the construction site near the I-9 ramps in Randolph, in the southbound direction. Data were collected on June 9, between :00 PM and 6:00 PM. There are three general-purpose lanes at this location. The hourly volumes ranged from 5,8 to 5,660 vehicles, totaling,078 vehicles during the two-hour period. The average vehicle occupancy across all three lanes was.0 persons per vehicle. Approximately,8 persons in,078 vehicles were counted. A MassDOT van was needed for safe data collection at this location.

4 Boston Region MPO April 0, 0 I-90/Mass Turnpike Eastbound Table shows summer 00 vehicle occupancy data for I-90/Mass Turnpike, eastbound, between exits and in Natick. Data were collected on June, between 7:00 AM and 9:00 AM. There are three general-purpose lanes at this location. The hourly volume ranged between,76 and 5,0 vehicles, totaling 9,08 vehicles during the two-hour period. The average vehicle occupancy across all three lanes was.9 persons per vehicle. Approximately 0,9 persons in 9,08 vehicles were counted. I-95 Northbound Table 5 shows summer 00 vehicle occupancy data for I-95 in Lexington, between exits 0A and 0B, in the northbound direction. Data were collected on June, between :00 PM and 6:00 PM. There are four general-purpose lanes at this location. The hourly volumes ranged from 5,089 to 5,87 vehicles, totaling 0,76 vehicles during the two-hour period. The average vehicle occupancy across all four lanes was. persons per vehicle. Approximately,79 persons in 0,76 vehicles were counted. I-9 Northbound Table 6 shows summer 00 vehicle occupancy data for I-9 in Wilmington, at the emergency pullout between exits and, in the northbound direction. Data were collected on July 7, between :00 PM and 6:00 PM. There are four general-purpose lanes at this location. The hourly volumes ranged from 6,98 to 6,65 vehicles, totaling,8 vehicles during the two-hour period. The average vehicle occupancy across all four lanes was. persons per vehicle. Approximately 5,96 persons in,8 vehicles were counted. A MassDOT van was needed for safe data collection at this location.

5 Boston Region MPO 5 April 0, 0 I-9 Southbound Table 7 shows summer 00 vehicle occupancy data for I-9 in Wilmington, at the emergency pullout between exits and, in the southbound direction. Data were collected on June 9, between 7:00 AM and 9:00 AM. There are four general-purpose lanes at this location. The hourly volumes ranged from 5,06 to 6,5 vehicles, totaling,60 vehicles during the two-hour period. The average vehicle occupancy across all four lanes was. persons per vehicle. Approximately,858 persons in,60 vehicles were counted. A MassDOT van was needed for safe data collection at this location. CONCLUSIONS Table 8 shows a summary of the results from summer 00 freeway vehicle-occupancy counts. Route southbound had the highest average weighted vehicle occupancy (.), while I-9 southbound had the lowest (.). The slightly higher occupancy counts on Route and Route may be partially explained by the proximity of the count locations to the southern end point of the Southeast Expressway HOV lane. At these locations, it may be assumed that a large proportion of northbound morning traffic was headed toward downtown Boston via the Southeast Expressway. The availability of an HOV lane along the Southeast Expressway may give drivers an incentive to seek higher-occupancy commuting options. The same is true for southbound afternoon traffic on Route ; a significant proportion of vehicles may have come from the HOV lane. The same effect was not observed at the I-9 location. Although traffic at this location was headed toward the I-9 North HOV lanes, occupancy here was the lowest (.). However, the count location is much farther from the I-9 North HOV lane, and would have captured traffic headed for I-95 as well. I-9 in the southbound direction also had the highest percentage of single-occupant vehicles (9%), while Route southbound had the lowest (80%). Percentages of twooccupant vehicles were highest at Route southbound (7%), Route northbound (%), and I-9 northbound (%), again suggesting HOV lanes have an impact on commuting decisions.

6 Boston Region MPO 6 April 0, 0 Results from the HOV monitoring performed by staff in the fall of 00 may reinforce this conclusion (see Appendices and ). The Southeast Expressway general-purpose lanes and HOV lanes were last monitored from 6:00 AM to 0:00 AM on Tuesday, November 6, 00. Between 7:00 AM and 9:00 AM, the average weighted vehicle occupancy (using the same weightings as were used for the general-purpose freeway occupancy counts described in this memo) was.60 for the northbound HOV lanes and.09 for the northbound general-purpose lanes. Assuming that both the summer 00 freeway occupancy counts and the fall 00 HOV lane occupancy counts represent typical morning traffic, it can be inferred that a substantial number of + person vehicles counted at the Route and Route locations were headed to or from the HOV lanes. For the counts done on June 9 and July 7, it is possible that holiday-related travel around the weekend of July th resulted in higher numbers of high-occupancy vehicles than normal, creating some bias in the data. However, efforts were made to avoid bias by scheduling counts during the middle of the week (Tuesdays and Wednesdays) and at least one day before or after the official holiday weekend. The two appended tables are from the memorandum, Observed Travel s, Occupancies, and Travel Savings: I-9 North and Southeast Expressway High-- Lanes, Fall 00 (Central Transportation Planning Staff, December 6, 00), pp. 6 and 8.

8 TABLE Route Northbound Counts June 5, 00 7:00 9:00 AM Start *** Average Weighted 7:00 8:00 AM 8:00 9:00 AM TOTAL 7:00 9:00 AM, ,59,96.0,5 09 0,706,6. 5, ,965 7,79. *Includes motorcycles, unmarked police vehicles, and taxis without passengers. **Includes limousines and other vehicles with blacked-out windows and vehicles for which visibility did not permit an accurate count. ***Assumes vehicle occupancies of 5.5 for vehicles, 0 for micro, 5 for, and for and Known.

9 TABLE Route Northbound Counts July 7, 00 7:00 9:00 AM Start *** Average Weighted 7:00-8:00 AM 8:00-9:00 AM TOTAL 7:00-9:00 AM, ,7 5,8., ,8 5,. 7,69, ,,8.

10 TABLE Route Southbound Counts June 9, 00 :00 6:00 PM Start *** Average Weighted :00 5:00 PM 5:00 6:00 PM TOTAL :00 6:00 PM, ,660 7,8.0, ,8 7,00.9 8,8, ,078,8.0

11 TABLE I-90/Mass. Turnpike Eastbound Counts June, 00 7:00 9:00 AM Start *** Average Weighted 7:00 8:00 AM 8:00 9:00 AM TOTAL 7:00 9:00 AM, ,0 5,99.8, ,76,98.9 8, ,08 0,9.9

12 TABLE 5 I-95 Northbound Counts June, 00 :00 6:00 PM Start *** Average Weighted :00 5:00 PM 5:00 6:00 PM TOTAL :00 6:00 PM, ,87 6,0.6, ,089 5,68. 9, ,76,79.

13 TABLE 6 I-9 Northbound Counts July 7, 00 :00 6:00 PM Start *** Average Weighted :00 5:00 PM 5:00 6:00 PM TOTAL :00 6:00 PM 5, ,98 8,08.5 5, ,5 7,98. 0,70, ,8 5,96.

14 TABLE 7 I-9 Southbound Counts June 9, 00 7:00 9:00 AM Start *** Average Weighted 7:00-8:00 AM 8:00-9:00 AM TOTAL 7:00-9:00 AM 6, ,5 7,0.0, ,06 5,65. 0, ,60,858.

15 TABLE 8 Summary of Results from Summer 00 Freeway Counts Location Direction of Traffic Date of Data Collection of Data Collection Number of Lanes Average Weighted Percent of with Person Percent of with Route Northbound Tuesday, June 5, 00 7:00 9:00 AM (including breakdown) 5,965 7,79. 88% 0% Route Northbound Wednesday, July 7, 00 7:00 9:00 AM 9,,8. 8% % Route Southbound Tuesday, June 9, 00 :00 6:00 PM,078,8.0 80% 7% I-90/Mass. Turnpike Eastbound Wednesday, June, 00 7:00 9:00 AM 9,08 0,9.9 88% % I-95 Northbound Tuesday, June, 00 :00 6:00 PM 0,76,79. 9% 8% I-9 Northbound Wednesday, July 7, 00 :00 6:00 PM,8 5,96. 8% % I-9 Southbound Tuesday, June 9, 00 7:00 9:00 AM,60,858. 9% 6%

16 Appendix I-9 Southeast Expressway Northbound General-Purpose and HOV Lane Counts November 6, 00 Lane Type *** 6:00 7:00 AM HOV, ,6,6.6 General 5, ,506 6,6. All 5,6,55 7 6,7 9,78.9 7:00 8:00 AM HOV 5, ,96, General, ,80,96. All,, ,676 8,00. 8:00 9:00 AM HOV ,00,65.6 General, ,6, All,87, ,56 7,58.7 9:00 0:00 AM HOV ,.66 General, , 6,06. All,970, ,78 8,59. 6:00 0:00 AM HOV, ,68,68.6 General 8,56, ,77,966. All 8,596, ,0,.8

17 Appendix I-9 Southbound General-Purpose and HOV Lane Counts November 7, 00 Lane Type *** 6:00 7:00 AM HOV ,7. General, ,957,80.8 All, ,70 5,. 7:00 8:00 AM HOV ,0.6 General, ,797,99.07 All, ,57 5,05. 8:00 9:00 AM HOV ,005.5 General, ,56,78.0 All, ,,789. 9:00 0:00 AM HOV ,6.00 General, ,87,.5 All, ,66 5, :00 0:00 AM HOV 58, ,06 8,.6 General 0, ,5,570. All,0, ,59 0,7.5

MEMORANDUM. for HOV Monitoring on I-93 North and the Southeast Expressway, Boston Region MPO, November, 2011.

MEMORANDUM. for HOV Monitoring on I-93 North and the Southeast Expressway, Boston Region MPO, November, 2011. MEMORANDUM Date: January 12, 2012 To: Congestion Management Process Files From: Seth Asante, Ryan Hicks, and Efi Pagitsas MPO Staff Re: Historical Trends: Travel Times and Vehicle Occupancy Levels for