When buses on 16th Street in DC are not moving, almost half the time they’re waiting at a traffic signal. Most of the rest of the time, they’re sitting at a bus stop, waiting for people to get on and off. Those are some findings from an ongoing study to speed up bus service on 16th Street.

16th Street buses bunching. Photo by Kishan Putta.

The S1, S2, S4, and S9 lines, which run along 16th Street, collectively carry about 20,000 people a day, over half of the total people using the street. The District Department of Transportation (DDOT) is studying the corridor in intense detail to identify the best ways to make the buses work as smoothly and speedily as they can.

DDOT planners have gathered detailed data on the buses from WMATA’s transponders, from actual human checks in March and June, and more. In August, they presented findings about where the delays come along the section in the study, starting north of Columbia Heights and down to H Street NW.

Buses are bunching up on the line a lot. Bunching happens during morning and evening peak times, in the middle of the day, and in the “early night,” from 7-11 pm. During rush hours, they are bunching even before they get to Arkansas Avenue heading south.

Buses are also taking longer to actually run the route than the printed schedule estimates. That makes bunching worse (and also frustrates riders who look at the schedules or use tools like Google Maps to plan trips.) Buses heading south in the morning are getting more delayed than evening buses going north.

Actually, the northbound buses are slower from 7-11 pm than during actual rush hour. This is likely because 16th Street does not allow parking during rush, but when parking starts, buses have to pull in and out of traffic at every stop. When there’s no parking, they just stop in the curb lane which is also the driving lane, and it’s drivers who have to merge to get around the bus instead of vice versa.

Image from DDOT.

DDOT planners generated this chart of what buses are doing. “Bus in motion,” 53% of the time, is when the bus is — as you’d expect — moving; it does include times it’s in some amount of traffic, but the biggest delays come from the almost half the time it’s not moving.

Of that time, the vast majority is either waiting at traffic signals (which also covers many times the road is traffic-choked, since then the buses will not be able to get through the lights), and the time the bus is waiting for people to get on and off.

Because so many people ride the S buses, the buses are crowded. That makes getting on and off even slower, since people have to wait for others to move out of the way.

The S9 express bus, in addition to making fewer stops, also has “low-floor” buses that involve fewer steps; this saves time as well. A transit industry reference manual says that on average, low-floor buses save about ½ second per rider. This, of course, can really add up.

Besides these larger findings, the planners looked at every spot along the route to find trouble spots. That includes bus stops where a lot of people generally get on and off (meaning the bus waits a long time), intersections that take a long time to get through, pairs of stops that are very close together, areas with heavy traffic, places the bus stop is really short (meaning buses have to wait to get in if there are more than one arriving), and more.

Here is a detailed diagram of all the potential trouble spots:

Click for the large version (PDF).

Next, the DDOT team will develop three specific scenarios and run them through traffic modeling to try to estimate what would do the most to reduce delays. That could include long bus lanes and short “queue jump” lanes, moving bus stops, programming signals to stay green longer when a bus is arriving, changing parking restrictions, letting people pay outside the bus, removing some bus stops, changing service patterns, or many other possibilities.

The team hopes to present these options in October and make recommendations by the end of the year.

David Alpert is Founder and President of Greater Greater Washington and Executive Director of DC Sustainable Transportation (DCST). He worked as a Product Manager for Google for six years and has lived in the Boston, San Francisco, and New York metro areas in addition to Washington, DC. He lives with his wife and two children in Dupont Circle. Unless otherwise noted, opinions in his GGWash posts are his and not the official views of GGWash or DCST.