Dedicating Asphalt to Bus Lanes

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).

Published by Will Brownsberger

Will Brownsberger is State Senator from the Second Suffolk and Middlesex District.

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  1. Bus lanes area smart idea as well as smart lights that communicate with the buses. As far as other areas. I have been trying to promote a Gondola system that would go from the South Boston Waterfront to near North Station.

    There are many ways to improve transportation, and dedicated Bus lanes are one of them.

    I also believe that one option for the Pike improvement at Allston would be to bury the Roads, and the Rail tracks at that stretch, thus connecting the neighborhoods to the Esplanade.

    1. No one is talking about a bus lane on the Belmont/Trapelo Corridor in Belmont. We’ve just gone through a major redesign and committed all the asphalt in ways that are hard to change.

  2. I agree with the open-minded approach that you are describing and agree that the goal should be to improve travel times (and experiences) for the greatest number of commuters whether in buses or cars. Clearly, improving bus travel will benefit the larger number of commuters so it is reasonable to give priority to this transit mode. More buses and less cars could also improve the experiences for the people still using cars.

    In the long run, it is likely that the number of commuters will continue to increase and the only practical way to support reasonable commute times and experiences will be to make more and greater improvements in mass transportation.

    I am glad to see that we are looking at the options that you describe and hope that further improvements will be made to attract more bus riders along these routes.

  3. Thank you very much for any work you do to bring dedicated bus lanes in segments where that improves matters. Buses in the MBTA system get way too much negative comment when the main problem (now that the creakiest of the old fleet seems mostly out of service) is really from too many drivers in single occupancy vehicles. Since no one’s mentioned global warming yet, let me, for inspiration, link to an interview with Kevin Anderson from this year’s COP:

    It’s simply too late in the game to piddle around. Electric cars won’t come soon enough. Those of us who can need to leave our cars in the driveway and not buy new ones.

  4. Speaking as one who has both driven through and stood on a bus driving through the Fresh Pond/Mount Auburn intersection during rush hour, I can attest that standing on crowded bus is much harder to do. Reducing time for buses to traverse this stretch of road would be a mercy.

  5. My main concern would be for residents and businesses along the route to have a strong voice in the decision process. In Cambridge they jammed through these poorly thought out bike lanes that have been disastrous for local businesses, and make parking, including for people with disabilities, virtually impossible.

  6. 1. I commute primarily by car.
    2. I, however, agree with dedicating lanes to buses and with TSP. Buses should have priorities over cars.
    3. I disagree with the bike lanes comment – as a driver, I am so very happy to have the bikes separated from me – like modern European cities have had for decades. Yes, there is less parking and I have taken my bike to more places for local shopping as a result.

  7. Thank You Senator Brownsberger,
    Managing increasing traffic congestion and making our systems as efficient as possible would reduce carbon emissions and make life easier for commuters. I look forward to a similar analysis of the routes in Allston Brighton. Not withstanding the complexity of the problem and coordinating a unified response across agencies and municipalities this is very important and necessary work.

  8. There would often be two to five fewer people standing on a crowded bus, in my case, #’s 65, 66, 57, and 86, if the instructions on how to lower the wheelchair seating area fold up seats were displayed clearly. Very few of us passengers know how to fold down the seats and fewer can find the instructions. It’s a minor inconvenience and won’t help the flow of traffic.

  9. This is a difficult problem and I applaud the effort to find ways to address it. Sounds good to me.
    Thanks, Mary

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