Search βΈ Agenda item attachment
A communication transmitted from Louis A. DePasquale, City Manager, relative to Awaiting Report Item Number 19-103, regarding a report 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:
December 11, 2019
Subject: Awaiting Report 19-103 β 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:
β’
Warrant 1 β β
Met β Eight Hour Vehicular Volume
o The traffic volumes show this warrant to be met for a total of 8 hours of
the day.
β’
Warrant 2 β β
Metβ Four Hour Vehicular Volume
o The traffic volumes show this warrant to be met for a total of 6 hours of
the day.
β’
Warrant 3 β β Not Met β Peak Hour Vehicular Volume
o Not applicable at this location
β’
Warrant 4 β β Not Met β Pedestrian Volume
o Pedestrian volume crossing Mass Ave does not meet the minimum
threshold of 107 pedestrians per hour during any time period.
β’
Warrant 5 β β Not Met β School Crossing
o Not applicable β nearest school is not proximate
β’
Warrant 6 β β Not Met β Coordinated Signal System
o Not applicable at this location
β’
Warrant 7 β β Not Met β 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.
β’
Warrant 8 β β Not Met β Roadway Network
o Not applicable at this location
β’
Warrant 9 β β Not Met β Intersection Near a Railroad Crossing
o Not applicable at this location
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.