A communication transmitted from Louis A. DePasquale, City Manager, relative to Awaiting Report Item Number 18-138, regarding speed limits and traffic calming measures

C I T Y O F C A M B R I D G E Community Development Department IRAM FAROOQ Assistant City Manager for Community Development SANDRA CLARKE Deputy Director Chief of Administration KHALIL MOGASSABI Deputy Director Chief of Planning 344 Broadway Cambridge, MA 02139 Voice: [phone removed] Fax: [phone removed] TTY: [phone removed] www.cambridgema.gov TO: Louis A. DePasquale, City Manager FROM: Iram Farooq, Assistant City Manager for Community Development Awaiting Report Item #18-138 regarding speed limits and traffic calming measures DATE: April 24, 2019 With respect to the above-referenced Awaiting Report we submit the following: Improving safety for all modes of transportation, including pedestrians, is a cornerstone of the city’s Vision Zero commitment. There are many tools for improving the pedestrian environment in Cambridge. The specific tools used at any location in the city depend on the issues at that location, context, and resources available. These include enforcement, education and various engineering methods including traffic calming, curb realignments, signs, pavement markings, and possible devices such as speed read out signs. TRAFFIC CALMING The traffic calming program in Cambridge has been a primary method for many years to reduce vehicle speeds by creating physical changes to the roadway, improving both safety and comfort of cyclists, pedestrians, motorists and nearby residents using City streets. Potential traffic calming projects are identified through a combination of residents’ requests, Council recommendations, and staff observations of speed issues. Projects are completed in conjunction with other roadway work scheduled in the City’s five-year streets and sidewalk plan. Designs are developed through a focused community process where residents can express traffic safety concerns and provide input pertaining to the neighborhood-related trade-offs of various speed control tools available. The traffic calming tools regularly used by the City include: Raised Intersection - Raised intersections make street crossing safer, easier, and more accessible by raising the intersection to the level of the sidewalk and slowing the speed of vehicles at intersections, where many conflicts occur with pedestrians, cyclists, and other drivers. Modified Raised Side-street Crossing – Crosswalks are raised to sidewalk level on side streets off major roads. These crossings are designed to make it safer for pedestrians to cross the street, to slow the speed of vehicles, and to make crossing with wheelchairs and strollers easier. Crosswalk – Clearly delineated crosswalks create a designated pedestrian crossing area, and alert drivers to look for crossing pedestrians. Curb Extension - Curb extensions visually and physically narrow the roadway, creating safer and shorter crossings for pedestrians, improving visibility for pedestrians and drivers, preventing illegal parking at corners, and slowing the

Page 2 of 2 speed of turning vehicles. Curb extensions also enhance the appearance of the street by increasing the available space for street furniture, benches, plantings, and street trees. Chicane - Chicanes are created by widening sidewalks or by alternating parking from one side of the street to the other. Chicanes slow the speed of vehicles by breaking up straightaways and improve the appearance of the street by providing areas for increasing landscaping. Travel Lane Narrowing – Narrowing the vehicle travel lane slows traffic by making it uncomfortable for drivers to travel at high speeds. This can be accomplished through construction, such as expanding the sidewalk, or through pavements markings, such as bicycle lanes or buffers. Rectangular Rapid Flash Beacon (RRFB) – RRFBs are pedestrian-actuated signals that supplement warning signs at unsignalized intersections or mid-block crosswalks. They can be activated by pedestrians manually by a push button or passively by a pedestrian detection system. RRFBs enhance safety at unsignalized intersections and mid-block pedestrian crossings by increasing driver awareness of potential pedestrian conflicts. Intersection Realignment - Realigned intersections are changes to intersection approaches and curb alignments, often converting "straight-through" movements into turning movements or “tightening” corners to slow vehicle turning speeds. Intersection realignments are useful for redesigning dangerous or confusing intersections, increasing pedestrian safety and for creating additional open space and plazas. Crossing Island/Median - Crossing islands make it safer for pedestrians to cross the street by allowing them to cross one direction of traffic at a time and reducing exposure time in the roadway or intersection. They also help slow the speed of vehicles by breaking up straightaways. Crossing islands are generally applied at locations where speeds and volumes make crossings prohibitive, or where three or more lanes of traffic make pedestrians feel exposed or unsafe in the intersection. Roundabout - A roundabout is a large island located where an arterial street intersects one or more crossing roads. It may replace a traffic signal. Vehicles are deflected from their path and must slow down as they turn into the circle but generally do not have to stop. Speed Read-out Signs – The effectiveness of these signs, which give feedback to drivers on their actual speed, is being reviewed and may be used in the future. Traffic Calming Project Measurements With the implementation of traffic calming projects, we have been able to lower the 85th percentile speed (the speed at or below which 85% of the drivers travel) on many streets. In some instances, a modified use of traffic calming tools has been focused on improving pedestrian safety. Project results are listed below:

Project Year 85% Speed Before (mph) 85% Speed After (mph) 85% Speed Change (mph) Traffic Calming Tools Used Cambridge Street 2017 31 25 -6 Narrowed travel lane (added separated bicycle lanes) Scott & Irving Streets 2015 30 28 -2 Raised intersection, crosswalks, narrowed travel lane, curb extensions Western Avenue 2014 32 24 -8 Narrowed travel lanes (added grade-separated bicycle lane), crosswalks, curb extensions Waterhouse Street 2013 28 (EB) 29 (WB) 22 (EB) 21 (WB) -6 (EB) -8 (WB) Curb extensions, raised intersection (removed traffic signal), narrowed travel lanes (added sidewalk) Lowell Street 2012 29 25 -4 Chicanes, crosswalks Brookline Street 2010 29 25 -4 Raised intersection, narrowed travel lane (widened sidewalk), curb extensions Blanchard Road 2010 38 (NB) 40 (SB) 33 (NB) 33 (SB) -5 (NB) -7 (SB) Raised intersection, narrowed travel lanes (added bicycle lanes) Brattle Street 2010 31 30 -1 Curb extensions, chicanes, crossing islands Upland Road 2008 33 (EB) 32 (WB) 29 (EB) 27 (WB) -4 (EB) -5 (WB) Chicanes, crosswalks, curb extensions Windsor Street 2007 29 (NB) 28 (SB) 24 (NB) 24 (SB) -5 (NB) -4 (SB) Raised intersection, curb extensions, crosswalks Concord Avenue 2002 37 (EB) 35 (WB) 32 (EB) 32 (WB) -5 (EB) -3 (WB) Crossing islands, curb extensions, rumble strips, crosswalks Holworthy Street 2002 31 30 -1 Raised intersection, curb extensions, crosswalks, bicycle lane, median reconstruction w/pedestrian crossing island on Fountain Terrace Rindge Avenue 2001 33 (EB) 34 (WB) 27 (EB) 29 (WB) -6 (EB) -5 (WB) Raised intersections, curb extensions, chicane, crosswalks, narrowed travel lanes Columbia Street 2000 31 27 -4 Chicanes, curb extensions, raised crosswalk, raised intersection, crosswalks Granite Street 1998 28 24 -4 Raised intersection, raised crosswalk, curb extensions, crosswalks, replaced signal at Pearl St with all-way stop Berkshire and York Streets 1997 30 24 -6 curb extensions, raised crosswalk, raised intersections, chicane, crosswalks, relocation of fence openings around Donnelly Field to line up with pedestrian crossings

Page 2 of 2 SPEED LIMIT In August 2016, state law changes allowed municipalities to adopt lower speed limits: Cambridge adopted a city-wide 25mph speed limit in December, 2016 and announced the creation of 20mph safety zones in February 2018. Prior to recent installation of the 20 mph Safer Squares Safety Zones, speed data was collected and we will be collecting post-implementation data for the squares later this spring to illustrate the impact that posting the zones has had on reducing speeds. In addition, this spring we will collect a representational citywide sample of pre-implementation speeds on the much larger number of streets where the speed limit will be lowered to 20 MPH, as requested by Council, with plans to later collect post implementation speeds for comparison. While multiple city departments collect speed data at specific locations in response to concerns about localized speeding issues or as part of enforcement activities, a comprehensive study of the adherence to the new citywide 25 mph has not been undertaken due to scope and cost using the standard speed measurement tools available. However, we are exploring and expect next year to have access to new data sources and tools to monitor traffic speeds across larger numbers of streets and longer time periods to better understand traffic speeds.