The Manager's report back on potential for a traffic signal at the intersection of Massachusetts Avenue at Garfield Street

Page1 of 2 MEMORANDUM To: Louis A. DePasquale, City Manager From: Joseph E. Barr, Director Date: Subject: Awaiting Report 19-103 – Potential for a traffic signal at the intersection of

Massachusetts Avenue at Garfield Street

This memo is in response to Order 33 from the July 30, 2019 City Council Meeting (Awaiting Report 19-103) to report on pedestrian safety concerns for pedestrians crossing Massachusetts Avenue at Garfield Street. The existing intersection provides a crosswalk across the side street approach and a crosswalk across Massachusetts Avenue on the south side of the intersection. Vehicle traffic at the intersection is controlled by a STOP sign on the Garfield Street approach.

The crosswalk across Mass Ave is supplemented by a flashing pedestrian beacon, with flashing lights located on both sides of the roadway as well as on the median. The beacon is pushbutton activated to warn drivers of pedestrians crossing the roadway. While the Garfield Street crosswalk is not controlled by a signal, signalized crossing opportunities are provided 400 feet to the north at Linnaean Street and 700 feet to the south at Wendell/Shepard Streets.

If traffic signal control were to be provided at this crosswalk, it would be through a full traffic signal controlling all approaches to the intersection. Installation of a

Pedestrian Hybrid Beacon (HAWK Signal)

Page 2 of 2 at this location would likely cause confusion for drivers approaching from Garfield Street, who would not be provided with signal indications and may be confused as to whether they may proceed. Installation of a new traffic signal is guided by a warrant analysis per criteria set forth in the federal Manual on Uniform Traffic Control Devices, 2009 Edition. There are 9 warrants based on a combination of safety criteria and the volume of roadway users. Our warrant analysis showed the following results for the Garfield Street intersection:

Warrant 1 – ✅ Met – Eight Hour Vehicular Volume

o The traffic volumes show this warrant to be met for a total of 8 hours of the day.

Warrant 2 – ✅ Met– Four Hour Vehicular Volume

o The traffic volumes show this warrant to be met for a total of 6 hours of the day.

Warrant 3 – ❌ Not Met – Peak Hour Vehicular Volume

Warrant 4 – ❌ Not Met – Pedestrian Volume

o Pedestrian volume crossing Mass Ave does not meet the minimum threshold of 107 pedestrians per hour during any time period.

Warrant 5 – ❌ Not Met – School Crossing

o Not applicable – nearest school is not proximate

Warrant 6 – ❌ Not Met – Coordinated Signal System

Warrant 7 – ❌ Not Met – Crash Experience

o This warrant requires five or more reported crashes, of types susceptible to correction with a traffic signal, within a 12 month period. Crash data from Cambridge police show an average of three crashes per year at the intersection.

Warrant 8 – ❌ Not Met – Roadway Network

Warrant 9 – ❌ Not Met – Intersection Near a Railroad Crossing

The analysis indicates that the installation of a traffic signal would be warranted based on the volume of vehicles at the intersection. Careful consideration must be given to the potential changes to traffic patterns in the adjacent neighborhood that may result from installation of a new signal. Improvement to the access to Mass Ave from Garfield Street would likely attract a significant number of diverted vehicle trips from other adjacent roadways. Based on other recent projects in Cambridge, we expect that the cost for construction of a new traffic signal would be approximately $250,000 to $300,000, and would thus require an appropriation of capital funds.