More trouble for transit tunnel

A day after thousands of commuters were delayed by a Downtown Seattle Transit Tunnel closure, engineers were trying to pinpoint why the tunnel and light-rail control system failed.

Their task shows how difficult it is to operate the city's unique transitway, where trains and buses mix.

A stream of "garbage data" poured into the Link light-rail control center in Sodo on Thursday, but a supervisor was able to manage the system using a control panel inside the tunnel. However, that supervisor then discovered the emergency phones in the tunnel didn't work, Link light-rail Director Ahmad Fazel said Friday.

The phone failure alone was enough to shut the city's transit spine during the busy evening commute to comply with fire and safety regulations.

It was the third major closure, all attributed to electronics, since the tunnel was renovated in 2007 to prepare for the $2.6 billion rail line last year.

Just before 5:15 p.m. Thursday, security guards shooed people from the underground stations and closed the steel-mesh gates. From there, riders found their normal buses on surface streets, took shuttles to meet their southbound Link trains at Stadium Station or gave up and hailed cabs.

The tunnel reopened early Friday, after engineers worked through the night to alter the electronic switches, so information could flow around the problem equipment, said Fazel. Work was planned early Saturday morning to restart the failed computers and switches.

Thursday's breakdown affected not just the tunnel but the entire 16-mile light-rail corridor. However, trains kept running beyond Stadium Station, using the still-functioning signals.

The tunnel is more sensitive because of ventilation fans, train and bus signals, fire alarms and other electric components — 5,000 in all. Sound Transit agreed to stringent safety rules with federal and city agencies to get permission to mix trains with buses.

Spreading the word

About 55,000 bus riders use the tunnel each weekday, along with most of the 24,000 riders taking trains, which run between Westlake Center and Seattle-Tacoma International Airport.

When the closure hit Thursday evening, some riders wandered around looking for information, although the overall customer-service response seemed quicker than last week, when a collision between a pickup and a train caused a three-hour Link shutdown in Rainier Valley.

Special shuttle buses for light-rail passengers hit the streets within 35 minutes. The fast response was a bright spot because it's tough to gather drivers and vehicles during rush hour, said Kevin Desmond, Metro general manager.

Signs at the stations explain where to catch buses in case of a closure — but there was no sign explaining where to catch the light-rail shuttle in the Chinatown International District.

The agencies published online rider alerts and sent Twitter messages, a plan Metro adopted since the ice storm of December 2008, when it left bus riders standing in the dark. An early alert incorrectly said the whole Link line was shut down, but was updated later. News media and blogs fed mobile-phone users, but many passengers lack such information pipelines. Live updates were given to riders by individual train operators and through the Stadium Station intercom Thursday.

Thursday's incident revives the question of whether government should send more personnel to greet the public when systems break down.

At Stadium Station, private Securitas guards pointed lost riders toward their bus or train platforms. That duty is part of their contract and ought to suffice, said transit managers.

Metro does send staff to transit stops around the county to steer people through major route changes. But during a sudden incident, "It's kind of challenging to draw people together at the drop of a hat," said Metro spokeswoman Rochelle Ogershok.

Nonetheless, such a "street team" is now being considered, said Sound Transit spokesman Bruce Gray.

Last week, the agencies hired a new customer-service employee to supply real-time messages from the control center to trains, buses and stations.

Making comparisons

Failures happen on Vancouver, B.C.'s automated SkyTrain, including one this week that required downtown trains to detour by sharing a single track. In October 2008, a communications shutdown in one train forced 17 trains to stop during the morning commute. But normally the closures happen on small segments, said spokesman Drew Snider.

"Stuff happens," he said. "It's not uncommon; we have workarounds, where we don't miss a lot of the system."

A signal failure caused tunneled segments of the San Francisco Muni network to close for three hours Sunday.

"The system we have here is much more reliable than the subway system I experienced in New York," said Desmond, who previously worked there.

Jarrett Walker, a consultant and author of the blog Human Transit, said the three Seattle incidents should be studied to see if there is a common element. On the other hand, "It may just turn out to be dumb luck."

"I think it's courageous that they're trying to use the tunnel so intensively, that so many people can benefit from it," he said.

Eventually, buses will be removed from the tunnel, after Link reaches Capitol Hill and Husky Stadium in 2016, and more trains go downtown. The tunnel signals can then be simplified and fire-suppression sprinklers removed, Fazel said.

Mike Lindblom: 206-515-5631 or mlindblom@seattletimes.com