Friday, September 26, 2008

Bus bunching

One of the major factors contributed to today's collision on Santa Clara Street is bus bunching, which is when a number of buses travel in a pack because of some late buses. Hours after the collision today, bus bunching continued on the line 22 in both directions throughout the afternoon.

Even though service on the Santa Clara Street east of downtown has a combined frequency of 6 minutes (lines 22 and 23), it is often unachievable because of bus bunching, especially on line 22. Bus bunching forces passengers to wait longer for a late and crowded bus, and makes the next bus that comes minutes after underutilized. Buses could end up leapfrogging each other.

Observations made after the collision:

While on a westbound 22 bus, it goes past a 22 bus (a non-articulated bus) just before downtown San Jose.

On the same bus at Santa Clara and 1st, the bus is about to pass another 22 bus stopped right in front.

The collision occurred at this location at Santa Clara and 23rd. Just a few minutes after this picture was taken, a pedestrian got hit on a crosswalk at Santa Clara and 24th by a turning car. This area is not particularly safe for pedestrians.

For the past 8 years, with all the wrong priorities, VTA has yet to implement a system that provides real-time bus arrival predictions. Such systems are already in use by Muni in San Francisco and AC Transit's BRT lines in the East Bay. Real time arrival predictions are valuable for riders in areas where service is less reliable or on lines that don't operate on a strict timetable (like the 522).

1 comment:

Thomas said...

The system that MUNI and some AC Transit uses is called "NextBus", which uses GPS. This was tested on the MUNI 22, the most unreliable line in the system, with promising results. I think the reason MUNI has it and not VTA or SamTrans is because the South Bay is more car-centric.