AGENDA

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• Welcome and Introductory Remarks (15 min) - Ken Carlson (Co-Founder, BU Bridge Safety Alliance)
• Outline of Recommended Improvements (15 min) - Peter Furth, (Co-Founder, BU Bridge Safety

Alliance; Professor of Civil Engineering, Northeastern Univ.)

• Stakeholder Perspectives (10 min)
• Pedestrians - Brendan Kearney (Executive Director, WalkMassachusetts)
• BU students - Jerry Zhou (President of BU Urbanists; BU Undergrad)
• Bicyclists - Galen Mook (Executive Director of MassBike)
• Progress and Plans from Agencies/Municipalities (30 min)
• Department of Conservation and Recreation - Jason Santos (Director of Transportation, Design

and Engineering) and AJ Tourigny (Ombudsman)

• Boston Transportation Department - John Monacelli (Principal Transportation Engineer)
• Mass. Department of Transportation - Benjamin Muller (District Planner)
• Questions (20 min)

Hybrid Zoom Meeting Protocol/Recording

• This is a hybrid Zoom meeting. Welcome, online guests and presenters!
• This meeting is being recorded.
• Two of our speakers are participating virtually.
• Please use the chat function on Zoom for virtual questions.
• Please hold your questions until after the presentations if you are in person.
• Crystal Huff is our Zoom moderator. They will be available via the chat function if you need help online.

A Moment of Silence for Road Traffic Victims This Year

World Day of Remembrance - Nov 17

Start: Cambridge Common

Goals for Today’s Meeting

• Share BU Bridge Safety Alliance’s recommendations for improving safety on the corridor.

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• Hear from state agencies and City of Boston about ongoing and planned safety improvements.

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• We want to hear from members of the public about their questions and concerns.

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• Encourage members of the public to stay engaged

(e.g. sign up for email updates - see clipboard signup or

email kencarlson8@gmail.com).

Thank you to:

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• Members of the Alliance

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• Colleagues at DCR, MassDOT, City of Boston

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• Everyone for showing up today

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• Boston University

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• Members of the Press

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• Elected officials

Boston University Bridge Safety Alliance

• Ken Carlson - Regional safe streets advocate
• Chris Cassa - Mem Drive Alliance, Cambridge Bike Safety
• Peter Cheung - Boston Cyclists Union
• Charlie Dennison - Livable Streets Alliance
• Dorothy Fennel - Transportation Planner
• Peter Furth - Northeastern University
• Crystal Huff - Mutual Aid Medford/Somerville
• Janie Katz-Cristy - Memorial Drive Alliance
• Scott Kilcoyne - Cambridge Bicycle Committee
• David Kroop - Bicycling Brookline

• Carl Larson - Boston University
• Steve Miller - Livable Streets Alliance
• Galen Mook - MassBike
• Ari Ofsevit - Memorial Drive Alliance
• Nathan Phillips - Boston University
• Dave Read - LMA Cyclists Network
• Jeff Rosenblum - Livable Streets Alliance
• Petru Sofio - Northeastern University
• Randy Stern - Cambridge Bicycle Committee, Cambridge Bike Safety
• Jerry Zhou - Boston University undergrad

Formed in Jan 2023 to address road safety issues on the BU Bridge corridor

Boston University Bridge Safety Alliance

• Ken Carlson - Regional safe streets advocate
• Chris Cassa - Mem Drive Alliance, Cambridge Bike Safety
• Peter Cheung - Boston Cyclists Union
• Charlie Dennison - Livable Streets Alliance
• Dorothy Fennel - Transportation Planner
• Peter Furth - Northeastern University
• Crystal Huff - Mutual Aid Medford/Somerville
• Janie Katz-Cristy - Memorial Drive Alliance
• Scott Kilcoyne - Cambridge Bicycle Committee
• David Kroop - Bicycling Brookline

• Carl Larson - Boston University
• Steve Miller - Livable Streets Alliance
• Galen Mook - MassBike
• Ari Ofsevit - Memorial Drive Alliance
• Nathan Phillips - Boston University
• Dave Read - LMA Cyclists Network
• Jeff Rosenblum - Livable Streets Alliance
• Petru Sofio - Northeastern University
• Randy Stern - Cambridge Bicycle Committee, Cambridge Bike Safety
• Jerry Zhou - Boston University undergrad

Formed in Jan 2023 to focus on improving traffic safety on the BU Bridge corridor

Boston University Bridge Safety Alliance

• Ken Carlson - Regional safe streets advocate
• Chris Cassa - Mem Drive Alliance, Cambridge Bike Safety
• Peter Cheung - Boston Cyclists Union
• Charlie Dennison - Livable Streets Alliance
• Dorothy Fennel - Transportation Planner
• Peter Furth - Northeastern University
• Crystal Huff - Mutual Aid Medford/Somerville
• Janie Katz-Cristy - Memorial Drive Alliance
• Scott Kilcoyne - Cambridge Bicycle Committee
• David Kroop - Bicycling Brookline

• Carl Larson - Boston University
• Steve Miller - Livable Streets Alliance
• Galen Mook - MassBike
• Ari Ofsevit - Memorial Drive Alliance
• Nathan Phillips - Boston University
• Dave Read - LMA Cyclists Network
• Jeff Rosenblum - Livable Streets Alliance
• Petru Sofio - Northeastern University
• Randy Stern - Cambridge Bicycle Committee, Cambridge Bike Safety
• Jerry Zhou - Boston University undergrad

Formed in Jan 2023 to focus on improving traffic safety on the BU Bridge corridor

BU Bridge Traffic Corridor

The bridge is narrow.

10’ travel lanes

5’ bike lane

5’ bike lane

9’ sidewalk

9’ sidewalk

10’ travel lanes

10’ travel lanes

Both ends have complex traffic conditions.

-------------------- 40 feet ----------------------

BU Bridge Traffic Corridor

It’s busy.

It’s multi-jurisdictional.

• DCR owns Memorial Drive, river paths and rotary
• MassDOT owns bridge and Comm Ave intersection
• City of Boston operates traffic signals @ Comm Ave
• MBTA operates bus service over the bridge
• City of Cambridge owns streets approaching bridge
• Town of Brookline owns streets to south of bridge

• Cars: 40,000/day
• Bikes: 2000/day
• Pedestrians: 1000’s/day
• Buses: Two MBTA routes; shuttle bus routes
• Many more people: traverse travel corridors parallel to bridge

BU Bridge Safety Alliance - Our Approach

• Brought together impressive group of advocates.
• Goal: Identify traffic safety improvements with primary focus on vulnerable road users.
• Operated within following constraints:

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• Spent first year developing/honing recommendations.
• Spent past year socializing improvements, gaining feedback and pushing for implementation

• Propose no change to number of travel lanes.
• Maintain if not improve vehicle throughput.
• Focus on quick build, low-cost improvements.

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Shared Recommendations with:

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• DCR
• MassDOT
• Boston Transportation Dept.
• MBTA
• Cambridge Traffic/Transportation
• Brookline Dept. of Transportation
• Boston University
• Charles River Conservancy

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• MassBike
• Memorial Drive Alliance
• Boston Cyclists Union
• Cambridge Bike Safety
• Livable Streets Alliance
• Walk Massachusetts
• Bicycling Brookline
• Cambridgeport Neighbors Assn.

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• Circulated a petition (>850 signatures to date)
• Held public meeting in Sept 2023
• Meeting with you all this evening

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Worked Closely with:

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DCR

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• Multiple meetings over past year (Senator Brownsberger helped initiate 1st mtg).
• Worked iteratively on plans to widen Paul Dudley White bike path.
• Already implemented some of our recommendations.

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BTD

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• Multiple meetings over past year.
• Focused on signal timing optimization.

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Make the BU Bridge Better for All Users�

Make it safer for bikes.

Make it safer and more convenient for pedestrians.

Reduce congestion, because that will:

- Decrease delay for buses.

- Decrease gridlock that traps Cambridgeport residents.

- Reduce crashes, particularly

in the rotary.

Students who helped with traffic signal & crash analysis:

• Petru Sofio
• Evan Wotton
• Fatemeh Tabatabaei
• Annie Etchells

What’s Wrong?

A. Pedestrian & Bike Safety

• Lack of protected bike lane
• Heavy right turn conflicts:
• Peds crossing Comm Ave
• Bikes crossing Mem Drive on-ramp

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Mouth of the BU Bridge at Mem Drive On-ramp

What’s Wrong?

B. Massive Congestion Makes Buses Slow and Unreliable, Traps Cambridgeport Residents

• Average southbound bus delay ≅ 7 minutes (pm peak, entering Boston)
• Bus delay often exceeds 13 minutes (90th percentile delay)
• Impacts Routes 47, CT 2, LMA buses
• Backups often paralyze Cambridgeport streets

What’s Wrong?

C. Too Many Crashes and Injuries

87 crashes reported between 2018-2022

• 15 bike crashes
• 2 pedestrian crashes
• Several 3- and 4-car crashes on the bridge, symptomatic of excessive congestion
• 2 autos crashed into Green Line trains in 2022
• At least 32 persons injured
• 55 crashes in the rotary

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See Crash Data Folder for more details.

Crash Map: Large yellow circles are crashes with 3+ parties. While map includes crashes on grade-separated roads (Mass Pike, Storrow Dr, Mem Dr overpass), they have been filtered out of the crash analysis.

Our Proposal: Low-Cost, Quick-Build,

Responsive to All These Issues

• Bike safety
• Protected bike lanes
• Signal separation at the Comm. Ave. and Mem Drive intersections
• Wider Mem Drive path
• Safety improvements to the Cambridge-side rotary

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• Pedestrian safety and service
• Signal separation, removing the conflict with right turn traffic at Comm Ave*
• Single pass crossings across Comm Ave*
• Synchronized pedestrian crossings for walking along Mem Drive

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• Relieve southbound congestion
• Increase southbound capacity (signal timing adjustments)

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* Championed by Boston Transportation Department

Peter

Safer for Bikes, #1: Protected Bike Lanes on the Bridge

Current

No separation from traffic.

Proposed

Flexpost-separated bike lanes for full length of the bridge.

Harvard St at Coolidge Corner (Brookline)

Museum of Science Bridge (MassDOT)

Flexposts are placed within the bike lane, so there is no change in travel lane width (10 ft).

Safer for Bikes, #2: Signal Separation Leaving the Bridge

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Distinct phases for bikes and right turns, at both Comm Ave and Mem Drive.

bike

car

Current

Bikes and turning cars get green at the same time.

15 sec

30 sec

car

bike

ped

Proposed

Distinct phases for bikes leaving the bridge and for right turns.

45 sec

Mem Drive intersection

Right turn volumes at both intersections demand signal separation.

Similarly at Comm Ave intersection (shown later)

Safer for Bikes (and Peds), #3: A Full-Width, Shared Use Path on Mem Drive

Current

Bikes headed west (down the ramp) have to use a narrow sidewalk.

Proposed

Shift the curb and convert bike lane space into bike path space.

Safer for Bikes, #4: Multiple Additional Fixes in the Rotary

• Protected bike lanes all around.
• Dual STOP signs instead of YIELD at bottom of Mem Drive down ramp.
• Only 1 circulating lane northbound and southbound.

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Pedestrian Safety & Convenience, Part 1: Signal Separation and Single Pass Crossing for Crossing Comm Ave

Current

Across western leg: After a 4-second head start, peds compete with heavy right-turning traffic

Across eastern leg: Peds heading south get only enough time to cross halfway.

Proposed

Middle 34 s

Peds, bikes, and thru traffic.

Final 25 seconds:

turning vehicles and thru traffic.

First 12 seconds:

turning vehicles and thru traffic.

Bike lane moved to the edge; middle lane converted to a right turn lane.

Comm Ave Intersection Video

Showing safety improvements and a 20% increase in southbound capacity

BUBridge at Comm Ave - Our Timing Plan_edited.mp4

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Another plan with same safety improvements but little or no increase in southbound capacity

BUBridge at Comm Ave - Timing Plan with Long RT red.mp4

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Ped Safety & Convenience, Part 2: Synchronize crossings so that pedestrians don’t have to wait twice; eliminate pushbuttons

• At mouth of the bridge, Cambridge side
• Coordinate signals within a 72-second cycle.
• “Trapezoid coordination” – one half-crossing’s phase starts sooner and ends later than the other in either direction; most people have enough time to cross in a single pass.

Also, Pedestrian Safety, Part 3 & 4: Wider Mem Drive path and fixes to the rotary.

26 seconds

16 seconds

West crossing

East crossing

time

Cambridge Side Intersection Video

https://youtu.be/YJr0JnyRxGo (YouTube link)

Reducing Southbound Congestion - It Takes Two

* Limiting bottleneck

Potential Timeline for Improvements

Stakeholder Perspectives

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• Pedestrians - Brendan Kearney (Executive Director, WalkMassachusetts)

• BU students - Jerry Zhou (President of BU Urbanists; BU Undergrad)

• Bicyclists - Galen Mook (Executive Director of MassBike)

Progress and Plans from

Agencies and Municipalities

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• Department of Conservation and Recreation - Jason Santos (Director of Transportation,

Design and Engineering) and AJ Tourigny (Ombudsman)

• Boston Transportation Department - John Monacelli (Principal Transportation Engineer)
• Mass. Department of Transportation - Benjamin Muller (District Planner)

Questions,

Answers,

and

Discussion

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