Concepts and cost estimates the city has been reviewing to rebuild the Northern Avenue bridge:
Rehab as a raised/stationary bridge: two lanes for cars in each direction, plus one lane in each direction for pedestrians and cyclists. This option involves the most preservation.
Build a new stationary bridge with two sidewalks and two lanes for cars.
Rehab as a moveable or stationary bridge to carry cars and pedestrians.
Rehab as a moveable bridge with a multipurpose lane that can carry vehicles and bikes, with sidewalks for pedestrians.
(Source: City of Boston)