Corridor and Network Development

SENSITIVITY ANALYSIS

Any transport demand forecast includes a degree of uncertainty. The best way to address this uncertainty is to develop BRT demand forecasts under different scenarios—both high-growth, transit-supportive scenarios, and low-growth, less transit-supportive scenarios. It would be helpful to deconstruct the individual components of the BRT demand under each scenario, showing the contribution of baseline transit ridership, mode shift from private vehicles, ridership from transit to new destinations, and landuse changes.

The BRT Standard defines a BRT corridor as “a section of road or contiguous roads served by a bus route or multiple bus routes with a minimum length of 3 kilometers (1.9 miles) that has dedicated bus lanes.” (See Appendix B: What is BRT? for more discussion about the building blocks of BRT.)

The proposed Everett‒Boston BRT corridor benefits from significant political support from the mayor of Everett. In this case, demand analysis (see previous section) is not informing corridor selection or prioritization; it will help inform whether the Everett‒Boston corridor is suitable for BRT, will provide adequate benefits to transit passengers, and will help induce transit-oriented development. Other steps in the development of the BRT corridor and network include analyzing transit speed and delays and optimizing the length of the corridor.

TRANSIT SPEED AND DELAY ANALYSIS

BRT corridor infrastructure offers the most benefit where existing bus operating speeds are very low. The slower the buses, the greater potential benefits BRT can deliver. Therefore, it’s worthwhile examining existing bus speeds in the Broadway and Rutherford corridors and understanding the common sources of delay and how the BRT might address those.

For the existing buses and the proposed BRT between Everett and downtown Boston, compare the time spent in each of the following states:

Free travel Dwell time (stopping and starting) Dwell time (boarding and alighting) Signal minimum delay Additional signal delay from traffic General traffic congestion

A BRT corridor’s dedicated lanes help reduce delays from traffic congestion. Median-aligned lanes reduce delays from turning vehicles. Off-board fare