Project Area
This project will include improvements to Main Street between Lafayette Square and Portland Street, connecting to Mass Ave via the Sidney Street Extension.
Main Street will eventually have separated bike lanes that connect Central Square to Kendall Square, including a mixture of quick-build and full-construction separated bike lanes. The Main Street Safety Improvement Project is one of several planned or in-progress projects that will add to this network, including the City's
Grand Junction Multi-Use Path Project and separated bike lanes being constructed by private developers.
Click here for a larger version of the project area map.
Project Schedule
Note: This schedule is based on the latest information we have and is subject to change.
March 16, 2023: First Community Meeting
- Project introduction
- Discussion of preliminary plans and opportunities for feedback
March 22, 2023: Community Open House
Spring 2023: Second Community Meeting and Second Community Open House
- Draft layouts and opportunities for feedback
Early Summer 2023: Third Community Meeting
- Revised layout
- Installation timeline
Summer 2023: Installation
The Cycling Safety Ordinance
In 2019, the Cambridge City Council passed the Cycling Safety Ordinance. The 2019 Ordinance requires the City to install separated bike lanes when:
In 2020, the Cambridge City Council passed amendments to the ordinance, requiring the installation of about 25 miles of separated bike lanes within the next five to seven years. The ordinance requires that the City install separated bike lanes on:
- All of Massachusetts Avenue
- Garden Street, eastbound from Huron Avenue to Berkeley Street and westbound from Mason Street to Huron Avenue
- Broadway from Quincy Street to Hampshire Street
- Cambridge Street from Oak Street to Second Street
- Hampshire Street from Amory Street to Broadway
- 11.6 miles in other locations from the 2020 Bicycle Network Vision
Learn more:
What drives our street design?
In Cambridge, we take a human-centered approach to street design, engineered to prevent errors as much as possible and lessen the impacts of errors when they do happen.
We design for all ages and abilities. This includes:
- Designing our streets for people who may not have access to a car
- Designing our streets to protect the most vulnerable road users, like cyclists and pedestrians
- Creating safe and accessible facilities, including bike lanes, that can be used by a wide range of people
Our focus is on moving people and goods, not their vehicles
- Biking and riding transit is a more efficient use of limited street space
- We keep access for trucks and local deliveries, but safely.
"Quick Build" Projects versus "Construction" Projects
This is a quick-build project, which means we are not digging into the ground or making changes to the width or shape of the road. Instead, we will make improvements using paint, flex-posts, stencils, new signage, changes to parking regulations, and traffic signal adjustments. Quick-build projects allow us to make changes to our streets more rapidly and to make adjustments even after a design is installed.
A construction project would involve more extensive changes, including moving curbs and/or removing medians. Work becomes more complex any time we dig into the ground, and construction projects usually include work on underground infrastructure such as traffic signal wires and water, drainage, and sewer pipes. When roads are reconstructed as part of the City’s Five-Year Plan for Streets and Sidewalks, roads designated for greater separation in Cambridge’s 2020 Bicycle Network Vision, including existing quick-build bike lanes, are turned into permanent separated bike lanes.
About Separated Bike Lanes
Separated bike lanes provide dedicated spaces for bicycles, physically separated from traffic by a vertical structure like a curb, flex-post, or other barrier. Compared to traditional bike lanes, more people are comfortable biking in bike lanes that are separated from traffic with a barrier or curb. The experience is also much more comfortable than riding in traffic with cars, buses, and trucks.
Separated bike lanes also increase safety for people walking by reducing crossing distances at crosswalks and visually narrowing the roadway width. As we install separated bike lanes, we also look for opportunities to increase visibility at intersections, refresh crosswalk markings, and install appropriate pedestrian crossing signs.
Key Components of Separated Bike Lanes
- Bike lanes create dedicated space for people who are biking.
- Buffers (painted lines on the street) create space between people biking and people driving. They help prevent unintentional collisions that could cause serious harm to the people involved. Depending on the location, there may be a parking lane next to the buffer area. In these instances, drivers can use the buffer area to safely get in and out of the car and to load and unload items.
- Flex posts are placed in the buffer area and serve as a vertical barrier in the buffer area.
- Travel lanes allow space for people to drive down the street, but can be used by anyone.
- Green markings help alert people turning from the travel lane that they should look out for people on bikes. These are generally installed at intersections and across driveways.
- Parking creates space for people to store their vehicles while they are in the area. This part of the street may also be designated as loading zones, which help make it easier for delivery people to do their jobs.
- Daylighting is when the parking lane is pulled back 20 feet to make it easier for people driving down the street and people waiting to cross the street to see each other. These areas are generally marked with lines on the ground. There may also be flex posts.
Mt Auburn St at Holyoke St - Before and After
The images below show Mt Auburn St at Holyoke St before and after separated bike lanes were installed as a part of the Inner Mount Auburn Safety Improvement Project.
Other Streets and Transportation Projects
Looking for information on other streets and transportation projects in the City? Three City departments collaborate on the design, community engagement, installation, and construction for street and transportation improvements: the Community Development Department, Public Works Department, and Traffic, Parking, and Transportation Department.
Through the Main Street Safety Improvement Project, the City will add separated bike lanes to Main Street between Massachusetts Avenue and Portland Street, creating a more-comfortable bike connection between the Port and Central Square. 
