Memorandum
Date September 20, 2012
TO Boston Region Metropolitan Planning Organization
FROM Karl H. Quackenbush
CTPS Executive Director
RE Work Program for: Safety and Operations Analyses at Selected Intersections—FFY 2013
Review and approval
That the Boston Region Metropolitan Planning Organization vote to approve the work program for Safety and Operations Analyses at Selected Intersections—FFY 2013, in the form of the draft dated September 20, 2012.
Planning Studies
13246
Boston Region Metropolitan Planning Organization
Principal: Efi Pagitsas
Manager: Chen-Yuan Wang
MPO 3C Planning Contract #69965
MPO §5303 Contract #70172
This is MPO work and will be carried out in conformance with the priorities established by the MPO.
This study builds on recommendations generated by the MPO’s Congestion Management Process (CMP) to address safety and congestion problems at intersections in the MPO region. Five similar studies in previous funding years have been completed or are underway and have received favorable responses from municipal administrators and directors of departments of public works. Municipalities in the region are receptive to this type of study, as it gives them potential low-cost solutions or a head start on conceptual design for intersections in need of attention for safety improvements and congestion mitigation.
Intersections dictate the quality of flow along an arterial, and therefore when improvements are made to their operations and safety, the safe processing capacity of that arterial can increase as a result. This can prevent the addition of traffic lanes from becoming necessary, result in fewer vehicle-miles of travel, reduce the use of neighborhood streets as “cut-throughs,” and enhance the reliability of any transit vehicles traversing the intersection. Most importantly, when intersections are managed and operated efficiently, safety improves as well.
The selected locations will be up to four individual intersections or sets of intersections that serve multiple transportation modes, including buses, bicyclists, and pedestrians.
The selection will be made from 20 potential locations of which intersections to analyze for safety and operations improvements.1 The potential locations will be identified based on a review of the MPO’s crash database and the CMP’s travel time and delay information. Intersections anywhere in the MPO region will be eligible to be selected for study. The improvement recommendations will be intended to enhance the intersections’ operations for all transportation modes, including transit, bicycling, and walking, and to enhance the safety of drivers, bicyclists, and pedestrians. The selected intersections may or may not call for improvements requiring right-of-way acquisition. Locations will be selected only if they are not currently under study by MPO staff or by others, or under design. One important basis for the selection will be input to the MPO staff from MassDOT and municipal officials, and the officials’ interest in project implementation. Other criteria are described below, under Task 1.
This study will identify improvements that address operational and safety problems at up to four intersections in the Boston Region MPO area.
This task will initially identify approximately 20 bottleneck locations throughout the region that have low levels of service and high vehicle crash levels. Staff will generate this list of intersections by employing a variety of strategies:
Up to four intersections will be selected for consideration from the initial 20, based on criteria in the following categories:
The potential locations will first be screened according to safety measures, including their Equivalent Property Damage Only (EPDO) crash-severity ratings, their numbers of crashes involving pedestrians or bicyclists, and their intersection crash rates. The locations will also be examined based on the need for improvements (safety needs, delays in processing of buses, intersection delays, queue length), ease of implementation (possibility of increasing capacity through signal retiming or upgrading; availability of right-of-way for minor geometry modifications), political support from the stakeholders, and cost considerations. Locations potentially requiring major geometry redesigns, such as grade separation or adding one or more travel lanes on an arterial, will not be selected. However, both short- and long-term improvements will be considered for the selected intersections. Finally, with regard to the third criterion bulleted above, staff will discuss with communities their level of interest in following up with implementation of the eventual recommendations. This is in addition to having solicited communities’ input during the selection of the 20 candidate locations.
A table listing up to 20 potential locations throughout the region, with four intersections selected for detailed study and the basis for their selection2
Once the four locations have been selected, staff will collect detailed data pertaining to each location. This will involve visiting each site and inventorying all relevant geometric, land use, and signal features. Data will include:
Summaries of count, signal, queue, and geometric data, as well as land use and jurisdictional information, for the selected locations
Staff will evaluate each intersection using various types of analysis. First, the crash data for each intersection will be analyzed with regard to crash type and severity and whether bicycles or pedestrians were involved in the crashes. Crash diagrams will also be constructed for the intersections with a crash rate exceeding the MassDOT Highway District average. Second, capacity analyses will be performed in order to determine the operational level of service at each intersection. Particular attention will be given to the evaluation of existing pedestrian signal phases, if any, or the need for them. Third, field observations will yield a full understanding of safety levels and of the operations of vehicles, including trucks, bicycles, and pedestrians at each location. One application of these observations will be in evaluating each location in terms of the “complete street” design concepts.
Summaries giving each of the selected locations’ incidence and types of crashes, its operational level of service, and an overall assessment of how safe or unsafe it is and how well or how poorly traffic is processed through it
Based on the evaluation performed in Task 3, staff will develop potential improvement alternatives with a preliminary estimation of construction costs. Staff will contact MassDOT Office of Transportation Planning and Highway Division District Office staff and local officials in each community involved in order to discuss the intersection summaries, receive input on the analysis and findings, and discuss potential improvements, including potential actions to promote implementation. The combined comments of local and state officials will steer the development of all final improvement recommendations.
A summary of discussions and other interactions with MassDOT Highway Division District Office staff and local officials with respect to the preliminary findings
Based on the evaluation performed in Task 3 and on the feedback given by local and MassDOT Highway Division officials, staff will consider the complete-street design concepts and recommend short- and long-term measures to improve operations and safety levels at the selected locations. Recommendations will include improvements for transit, specifically buses that may pass through the intersection; these could include curb extensions, bus stop relocations, and transit signal priority options. The cost of the measures will be estimated and the jurisdictional entity or entities responsible for implementation identified.
A summary of recommended operations and safety improvements for the selected locations
Staff will document all study tasks in a technical memorandum. Each of the communities involved will also receive a technical memorandum providing the analysis and recommendations pertaining to its particular location or locations.
Technical memoranda summarizing the study of each intersection or intersection set, including documentation of the correspondence with municipal officials
It is estimated that this project will be completed 12 months after the notice to proceed is received. The proposed schedule, by task, is shown in Exhibit 1.
The total cost of this project is estimated to be $67,658. The total cost includes the cost of 24.3 person-weeks of staff time, overhead at the rate of 96.58 percent, and travel. A detailed breakdown of estimated costs is presented in Exhibit 2.
KQ/EP/CW/cw
1 The number of locations selected for study will depend on the complexity of the analysis required by the selected locations. That is, if one or more of the intersections that are given the highest priority for inclusion in the study require particularly time-consuming analysis, the number of locations studied may be fewer than four.
2 The table will include information explaining why the locations were chosen using safety concerns, potential for improvement, and municipal interest in implementation as criteria. Staff will make a presentation to the MPO on the selection process and results and seek its approval on the intersections staff recommends studying in detail.
Task |
Month | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | |
1.
Select Locations |
From month 1 to 2.
Month 2, deliverable A, A table of the selected locations with information on basis for selection.
| |||||||||||
2.
Perform Field Reconnaissance and Collect Data |
From month 2 to 2.5.
From month 6 to 9.
Month 9, deliverable B, Summaries of intersection data and information.
| |||||||||||
3.
Evaluate Selected Locations |
From month 7 to 10.
Month 10, deliverable C, Summaries of crash characteristics, level of service, safety assessment, and traffic flow.
| |||||||||||
4.
Develop Alternatives and Receive Input |
From month 8 to 11.
Month 11, deliverable D, Summary of discussions and interactions with communities and MassDOT Highway Division Districts.
| |||||||||||
5.
Recommend Improvements |
From month 10 to 12.
Month 12, deliverable E, Summary of recommended operations and safety improvements.
| |||||||||||
6.
Document Findings and Recommendations |
From month 1 to 13.
Month 13, deliverable F, Final technical memoranda.
|
Task |
Person-Weeks | Direct Salary |
Overhead (96.58%) |
Total Cost |
|||||
---|---|---|---|---|---|---|---|---|---|
M-1 | P-5 | P-2 | SP-3 | Temp | Total | ||||
1.
Select Locations |
0.5 | 2.0 | 0.0 | 0.0 | 0.0 | 2.5 | $4,202 | $4,059 | $8,261 |
2.
Perform Field Reconnaissance and Collect Data |
0.0 | 1.5 | 1.6 | 2.0 | 3.0 | 8.1 | $6,944 | $6,706 | $13,650 |
3.
Evaluate Selected Locations |
0.0 | 2.2 | 0.0 | 0.0 | 0.0 | 2.2 | $3,691 | $3,565 | $7,256 |
4.
Develop Alternatives and Receive Input |
0.5 | 4.0 | 0.0 | 0.0 | 0.0 | 4.5 | $7,558 | $7,299 | $14,857 |
5.
Recommend Improvements |
1.0 | 1.5 | 0.0 | 0.0 | 0.0 | 2.5 | $4,211 | $4,067 | $8,278 |
6.
Document Findings and Recommendations |
2.0 | 2.5 | 0.0 | 0.0 | 0.0 | 4.5 | $7,583 | $7,323 | $14,906 |
Total |
4.0 | 13.7 | 1.6 | 2.0 | 3.0 | 24.3 | $34,189 | $33,019 | $67,208 |