At the morning rush hour, one would be easily forgiven if one were to look at Mount Auburn Street in Cambridge approaching Mount Auburn Hospital and see a whole lot of people sitting in cars.
Yet, according to a recent throughput analysis, the majority (56%) of people wading through that rush hour traffic are packed on the buses coming from Watertown (#71) and Waverley (#73). These two bus routes are, according to another recent study, the two most crowded routes in the MBTA system.
The MBTA’s recent call to create more dedicated bus lanes reflects this fundamental reality: In many congested road segments, a large share of the people are hidden away in buses, many of them standing. They are much less comfortable and less able to tolerate stop-and-start delays than people in their own private cars. Where the data prove high bus ridership, it is common sense to shift road resources towards the buses.
The recent traffic analysis on Mount Auburn Street was done as part of a large design study of that road segment. The big ideas coming from that study are: (1) to realign the intersection of Fresh Pond and Mount Auburn to reduce the dead space in the middle which takes seconds from every light cycle to clear; (2) to create a dedicated bus lane in the segments where traffic currently queues up; (3) to give buses priority to move forward and out through the intersections in that stretch.
The result will be savings of 2.4 minutes per trip for the buses and a loss of about 44 seconds for cars. All together, people — bus riders and drivers — will on average save 140 seconds per trip. That is a big win.
Transit signal priority is the more general idea of making sure that traffic gets a green light when a bus is waiting (possibly including cars if the lanes is not dedicated). The MBTA is making good progress on TSP as I wrote recently. If we can combine the intersection improvements on Mount Auburn with transit signal priority at other points along the 71/73 corridors, then we knock enough time off the round trips that we can get a meaningful increase in total capacity. Shorter round trips means more round trips and smoother flow means less bus bunching. So, the service could noticeably improve.
If we can get service to improve, that may attract more riders, in turn taking cars off the congested corridor, improving travel times for everyone. We should hope and work to create a virtuous cycle of transit service improvement.
Although the crowding on the 71 and the 73 stands out, there are many other heavily-used routes that need similar attention in Allston and Brighton and Watertown.
In every case, fragmentation of responsibility and concerns makes it harder to identify the opportunities and to get projects moving. For example, in the Mount Auburn case, some of the roads are controlled by the state’s Department of Conservation and Recreation, some by the Cambridge and, at the project edges, segments are controlled by Watertown and Belmont. Proposed traffic flow changes would require investments by the MBTA to move the overhead electric lines that power the trolleys. The state’s Department of Transportation is a necessary funding partner. Several different neighborhood organizations have strong views on parts of the project that touch their space.
That is the continuing challenge for state and local leaders at all levels — to build and sustain the partnerships necessary to make real improvement happen.
A recent Watertown Tab story about bus lanes reflects progress on a component of the project discussed above. Cambridge is working with DCR to coordinate the necessary road striping (owned by Cambridge, mostly) and signal changes (owned by DCR mostly). At a recent DCR meeting about the overall project, this aspect was not fully discussed because Cambridge is leading it. However, it is part of the same design vision (same design consultant).