Derailment Shuts Down Muni Metro Service in Twin Peaks Tunnel

Riders hustle from an inbound shuttle bus to Castro Station. Photo: Michael Rhodes

A train derailment in the Twin Peaks Tunnel disrupted Muni Metro service between Castro Station and West Portal Station today, extending into the evening commute. The middle section of the second car of an outbound L-Taraval train came about a foot off the track in the tunnel at about 7:35 a.m., according to MTA spokesperson Judson True.

No injuries were reported, but the tunnel shutdown heavily disrupted morning commute service as riders packed onto shuttle buses between the affected stations. More than 20 buses were shuttling between West Portal and Van Ness Station. Inbound service at Castro Station was also briefly disrupted as Muni crews dealt with a crossover issue, but was restored by 9:10 a.m.

This afternoon, Muni officials announced the tracks had been inspected and deemed safe, but that they would have to do a test run before service could resume, and it would not be in time for the afternoon commute. Service in the Market Street tunnel is also slower than usual as a result.

The Twin Peaks Tunnel was extensively rehabbed between January 2006 and early 2008. A derailment in a similar location in 2006 took most of the day to clear out, and caused damage to overheard wires in the tunnel.

MTA spokesperson Judson True and a Muni supervisor discuss the derailment.

At 9:30 a.m., the derailed vehicle was still in the tunnel, though its passengers had exited the tunnel aboard a separate train. An Automatic Train Control System communications loop was damaged in the derailment, said True, and the MTA was working to repair it and remove the train. An estimate of any damage to the train was not yet available.

The MTA has notified the California Public Utilities Commission (CPUC), which oversees safety on the state's light rail systems, of the derailment. The MTA was reviewing the incident this morning, and is the designated investigative agency for Muni, but the CPUC could also investigate if they choose to.

In a separate incident this morning, a J-Church light rail vehicle collided with an automobile at Church and Jersey Streets, and train service was replaced with bus shuttles between the crash site and Balboa Park Station for about an hour. Today's interruptions, as well as yesterday's unscheduled extension of track work on the N-Judah, leaves the T-Third as the only Muni Metro line not to have an unplanned service disruption this week.

Update, 5:23 p.m:

As the evening commute begins, Muni Metro service between Castro and West Portal Stations is still delayed. True said staff are now hoping for a late evening re-opening of the Twin Peaks tunnel, likely not in time for any part of the evening peak crowd.

Crews were still working to re-rail the train, though the ATCS communications loop had been repaired, clearing the way for automated train control in the tunnel when service resumes. Once the train is re-railed, crews will run a test train to determine if the tunnel is safe for service.

MTA inspectors were inspecting the tracks as of 2:45 p.m., and determined them to be safe for service. As the investigation and repair work continues, Muni riders are encountering a chaotic commute in many parts of the system, and service is still not at full speed in the Market Street Tunnel.

True said MTA staff members are mobilizing to assist riders during the service outage. During the morning commute, a lone Muni employee was directing passengers at Castro Station, as MTA staffed scrambled to react to the derailment.

Update, 6:29 p.m.:

The L-Taraval train has been re-railed and moved out of the tunnel, but still no estimate for when service will resume between Castro and West Portal Stations. Test runs and track inspections are in progress, and True said the MTA is still investigating what caused the derailment.

The derailment is the first in the tunnel since August 2006.

Update, 7:44 p.m.

Service has been restored between Castro and West Portal Stations, True reports. Bus shuttles will continue to provide supplemental service between those stations "until the Muni Metro system resumes its normal schedule."

The investigation continues, and still no word on what caused the derailment.

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