Report: 39 bus mostly on time

August 10, 2007

John Ruch

The MBTA’s Route 39 bus service recently ran on schedule about 90 percent of the time, according to an unscientific survey conducted by local residents.

The longest recorded wait for a bus was 28 minutes, and plenty of “bunching”—two or more buses traveling together—was observed.

But about 64 percent of buses ran strictly on time. Of buses that ran technically late, the vast majority were late by five minutes or less. The MBTA still counts that as on time as part of what spokesperson Joe Pesaturo called “a transit industry standard.”

“Of course, we’re always aiming for 100 percent of the trips to be less than five minutes late,” Pesaturo said in an e-mail to the Gazette.

The survey was conducted by two residents who wish to remain anonymous, but are not involved in the controversy about whether trolleys or buses are better for the corridor. One of the residents is a regular 39 rider.

The 39 bus is technically a replacement service for the Arborway trolley between Heath Street and Forest Hills, which the MBTA “temporarily” suspended in 1985. It parallels the Green Line’s E Branch for much of its route.

The residents said they conducted the survey out of curiosity amid many word-of-mouth complaints that the bus runs late. Route 39 service was the target of complaints in recent articles of the commuter-oriented newspaper BostonNOW.

The residents sat and observed buses, timing the gaps between their appearances, over several days at a location in central Jamaica Plain, and one day at the Museum of Fine Arts. The survey was conducted in May and earlier this month, covering periods of at least one hour on each day of the week. Weekday observations were conducted at varying times of day to include both rush hour and off-hours.

The residents provided raw, hand-written data to the Gazette. The Gazette then compiled and analyzed the data. The Gazette was aware the survey was being conducted, but did not participate or advise the residents.

The count covered 58 “observed” buses. That does not necessarily include the first observed bus, because it usually was unclear if that bus was on time or not. On the other hand, the count includes some unseen buses: if a bus had not appeared on schedule by the time the resident observers quit for the day, the Gazette counted that as a late bus.

The survey is not scientific and only reflects what riders experienced on those particular days and times. Major qualifications are that the survey was conducted when there was no snow to slow traffic and when much of Boston’s college student population was gone. Also, part of the survey was conducted when Boston Public Schools were out of session and not generating traffic.

Pesaturo did not respond to a Gazette request for official service statistics to compare with the resident observations.

Unsurprisingly, the survey showed weekday service slower at the tail end of morning rush hour and best in the noontime slot. Several times, buses appeared well under the scheduled waiting time.

The worst service day observed was Sun., July 15. Outbound (toward Forest Hills) buses ran in bunches, in one case resulting in a 28-minute wait when the official schedule calls for service “every 11 minutes or less.”

“The reported 17-minute delay is somewhat surprising,” Pesaturo said, “but that could be due to any number of factors, including unusual traffic conditions (perhaps special-event-related or an accident), a possible mechanical problem with a bus, etc.”

Inbound (toward Back Bay) Sunday service was much better, as would be expected from observations made close to Forest Hills. However, when the observers quit for the day, a bus had not appeared for 21 minutes, making the next one at least 10 minutes late.

Bus bunching was observed in virtually every session. The MBTA generally attributes bunching to one bus getting slowed by traffic or passenger boarding issues, and the next bus catching up.

“Occasional ‘bunching’ is virtually unavoidable because there are so many buses on the route during rush hour that a very slight delay on one can result in the following bus catching up,” Pesaturo said.

However, the survey noted bunching on two different weekdays occurring inbound, less than a mile from Forest Hills. That might suggest some sort of problem with buses leaving on time rather than traffic issues.

An example of inbound bunching occurred on Wed., May 30, around the 9-10 a.m. slot, when buses are supposed to run “every six minutes or less.” In one case, a bus finally arrived after an 11-minute wait, followed by another only two minutes behind it.

Bunching is something of an invisible problem in the survey, because the second bus, at least, will always count as “on time” because it arrives so quickly. But the irregularity of the service during bunching remains an inconvenience.

The MBTA does not publish specific arrival/departure times for every stop on the route because buses could never be that precise. The schedule is specific only for the ends of the route and the Heath Street Green Line transfer point. The Gazette judged “on time” based on the general number of minutes between the official arrival/departure times at the end of the lines.