What if buses reported every blocked bike lane?

The Massachusetts Bay Transportation Authority (MBTA) starts using cameras on its SL4 and SL5 buses on October 1, 2026 to automatically give tickets to people parked in bus lanes and bus stops, under a January 2025 state law. But bus-mounted cameras do not need a bus lane to see a blocked bike lane!

Volunteers for the Bike Bureau have reported 4,904 people parked in bike lanes across Greater Boston from June 1 through September 26, 2026, of which 3,640 fall along a regular MBTA bus route. That means nearly three-quarters of reported bike-lane blockages already occur on streets regularly traveled by MBTA buses—putting thousands of violations within reach of the same camera technology.

Which shared bus/bike lanes are blocked the most?

Many of the bus lanes to be enforced also allow bicycles, we charted them alongside Bike Bureau reports. The map contains 293 reported obstructions and 36 corridors. Click a corridor to inspect it; orange dots are reports of blocked bus lanes and white dots are stops. We can see exactly where the new camera program has the greatest opportunity to keep space clear for both buses and bikes.

How the maps were made

The first map uses the MBTA’s published GTFS route shapes, excluding temporary rail-replacement shuttles. We matched the June–September reports to the nearest regular bus-route alignment within 25 meters. That distance is a practical approximation of “the same road”; intersections, parallel streets, GPS error, and route changes can produce imperfect matches.

The second map uses bus-lane geometry and stops from OpenStreetMap. We included ways tagged as shared busways for bicycles and on-street bus-lane corridors, then split same-named streets into separate corridors wherever their lanes are more than 1.2 km apart (so Washington Street in the South End, Jamaica Plain, and Somerville are listed separately). Thin lines connect the bus-lane pieces of a corridor along the MBTA route that runs through the gaps; only the thick segments are actual shared lanes, and corridor lengths count only those. Bike Bureau reports were matched within 30 meters. Stop totals are based on OpenStreetMap points near each corridor. Both maps are snapshots, not complete inventories of every obstruction.

References

1. Loud Bicycle. “Bike Bureau.”
2. Loud Bicycle. “Bike Bureau: Download Data.”
3. Lansey, J. “Reporting Cars in Bike Lanes: A History of Citizen Enforcement.” BikeResearch, 2026.
4. OpenStreetMap contributors. “OpenStreetMap.”
5. Massachusetts Bay Transportation Authority. “GTFS Static.”
6. Massachusetts Bay Transportation Authority. “MBTA Bus Stop and Bus Lane Automated Camera Enforcement Program Begins October 1, 2026.” September 24, 2026.
7. MilNeil, C. “Smile, Gov. Healey Signs Two Camera Enforcement Bills for Buses.” Streetsblog Massachusetts, January 10, 2025.