Over 50 percent of reported bike crashes that occurred on Commonwealth Avenue in Boston during a four-year stretch involved a bicyclist being hit or coming in contact with a car while riding in the designated bike lane.

There were 100 bike crashes reported on the entirety of one of Boston’s busiest stretches, the stretch of Comm Ave flanked by Boston University, between 2009 and 2012. In the area between Packard’s Corner and West of the BU Bridge alone – an area currently targeted for multi-million dollar reconstruction project – 58 crashes occurred; the top cause of reported crashes involved motorists unknowingly cutting off bikers while making a right turn at an intersection, while the second highest percentage of bike crashes was “dooring” – bikers slamming into recently swung-open car doors.

Paul Schimek, an independent researcher and author of a new bike injuries study, describes how over half of these bike crashes happened: “Cyclists were riding in the bike lane and were “struck by a suddenly opened car door or by a motorist turning right across the bike lane.”

In reported incidents, about 30 percent of bicyclists escaped with only minor or no injuries, and did not require treatment by emergency medical services; moreover, only 26 percent of bikers treated in emergency rooms, Schimek found, citing state Department of Public Health data pertaining to Boston, and even for the more serious cases, where the bicyclist was admitted to a hospital overnight, only 40 percent had been in a collision with a motor vehicle.

While Schimek’s study analyzed – specifically – 100 reported motorist-bicyclists crashes on Boston’s busy Comm Ave over a sample four-year time period, “There are many more bicyclist injuries than those reported to the police,” Schimek concluded in his study, adding that bikers are more likely to get hurt after riding over a pothole, catching an edge on the trolley tracks, simply losing control of their bikes, or running into a pedestrian – crashing into or being hit by a car is not as likely.

All 100 police-reported crashes on Comm Ave that involved bicyclists (Kenmore Square to Brighton Ave):

Subsample of 58 of crashes in planned reconstruction area (Packard’s Corner to BU Bridge):

“Conventional wisdom,” Schimek states in his study, “says that bicyclists are run down from behind, but there was only a single case of a bicyclist struck by an overtaking motorist in daylight, resulting in ‘minor scrapes.'” Only 10 percent of the crashes (listed above) that took place between 2009 and 2012 involved a party being written a citation from Boston police.

Those citations were:

  • Opening a door unsafely (4 citations)
  • Failure to yield when turning right on red (1 citation)
  • Operating under the influence of alcohol (1 citation)
  • Leaving the scene of an accident (1 citation)
  • Operating without a valid Mass. drivers license (3 citations)
  • In an email Sunday night, Schimek, who is currently working on a study of Boston bike injuries, shared his initial report with BostInno. Schimek suggested in his email that his findings could provide added context to a previous August 27 report by BostInno, which focused on a proposed $16 million reconstruction plan for Commonwealth Avenue. As currently envisioned, this plan would narrow sidewalks, widen MBTA tracks – the B Branch of the Green Line – and add three feet of additional space, a “bike lane buffer,” to either side of the street, according to Boston Transportation Department Interim Commissioner James Gillooly.

    In short: Comm Ave bike lanes don’t provide the best protection for bicyclists and motorists still pose a threat to threat to bikers’ safety – but they’re far from the only danger. Schimek’s study (read the full version, below) found that bicyclists themselves in many cases could have prevented crashes from occurring.

     Here’s a rundown of bike crashes/injury findings and safety suggestions from the study:

    • Nearly every reported crash involved at least one party violating traffic laws; citations were given in fewer than 10 percent of cases – one was given to a bicyclist;
    • Schimek suggests targeting traffic enforcement to specific crash types, such as, and especially: improper right turns, unsafe door opening; signal violations; failure to use lights, drunk driving, and harassment of bicyclists;
    • Bike safety awareness should be promoted to help bikers understand various ways of avoiding potentially dangerous traffic scenarios;
    • The public should be made aware of bikers right to use the roadway – outside of the bike lane;
    • An additional 3-to-4-ft. buffer zone should be added to a 4-ft. bike lane and parking lane; and
    • A short, 50-ft. right-turn-only lane should be added at intersections to provide motorists room to merge right prior to turning;
    • A proposed cycle track could have eliminated only a handful of crashes; a change in bicyclist behavior might have helped avoid “almost all of these crashes,” Schimek reports.
    • A buffer from parked cars, not a physical barrier from moving cars, would reduce crashes.

    While widening Comm Ave would provide more space for bicyclists – and motorists – the design of the bike lane is itself flawed; adding a buffer zone would not necessarily protect bikers, who themselves need a refresher course in the rules of the road to make travel safer. Design improvements, he suggests, must be made and public awareness campaigns must continue promote bike safety to reduce crashes and injuries.

    To read Schimek’s full 35-page report, keep scrolling down.

    Comma Ve Report Sept 22 by Nate Boroyan


    Correction: An earlier version of this report said 58 of 100 crashes occurred in bike lanes between Packard’s Corner and the BU bridge. The subsample of 58 crashes occurred in that area, but not in specifically in protected bike lanes. Additionally, Schimek’s study targeted four, not three, years of data. The post has been updated.