Severe shutdown ahead for Seattle light rail due to sinking tracks

Of all the obstacles Sound Transit could encounter since breaking ground for light rail in 2003, sinking tracks were the furthest from anyone’s mind.

Yet two decades later, the rails are sagging next to Stadium Station, where repair crews will block the trains this weekend, followed by a week of slowdowns. This major maintenance, along with platform tile replacement at Othello and Rainier Beach stations later this month, will disrupt service to 80,000 daily travelers.

The most severe shutdown comes Saturday and Sunday where the tracks are sinking 3 inches as they cross Royal Brougham Way South, between Stadium and International District/Chinatown Stations. (Pedestrian walkways will remain open.)

While track work blocks that spot, Sound Transit will bundle this closure with seven other repair jobs downtown to close a total five stations all weekend.

Buses starting at Sodo and Capitol Hill stations will shuttle people to the temporarily closed Stadium, International District/Chinatown, Pioneer Square, University Street, and Westlake stations.

After that, trains will alternate on a single track seven days, Aug. 14-20, across Royal Brougham Way, slowing the entire 24-mile line from Northgate to Angle Lake. Trains in both directions will arrive 15 minutes apart, rather than the usual 10 minutes. Riders must change trains at Pioneer Square Station, to go between the north and south sides of the city.

The Pioneer Square switcheroo will be similar to early May, when trains detoured around a punctured ceiling section at Westlake Station. But arrivals won’t be synchronized this time, so some people might wait a minute, while others wait 12-plus minutes after taking an escalator climb and mezzanine walk between boarding platforms at Pioneer Square.

Another service disruption goes from Aug. 21 through Sept. 17, when contractors replace prematurely broken tiles at Othello and Rainier Beach stations, which opened in 2009. Trains will single-track in that area, as the whole 1 Line operates at 12 minutes between trains. The yellow platform tiles were replaced last year at Columbia City Station.

Suraj Shetty, executive director of operations, said there are seven tasks scheduled downtown this weekend. These include inspecting high-voltage power equipment, building track ties near International District/Chinatown Station for the overdue 2025 Bellevue-Seattle extension, and replacement of aging rails inside the downtown transit tunnel.

In addition to train disruptions, Royal Brougham Way South will close to motor vehicles between Fourth and Sixth Avenues South, from Wednesday night until early Aug. 23, to allow for site preparation and for new concrete to cure. Sidewalks will remain open.

Ordered slowdowns

The $750,000 repair will include leveling the tracks, replacement of concrete panels beneath and alongside the rails, and adding fill sediment below the surface.

For several months, Shetty said, train speeds in this location have been limited to 10 mph, and 5 mph on rainy days, to prevent further damage.

Shetty said his theory is that the weak fill soil, deposited on Sodo tideflats during early 20th century hill regrades and debris disposal, succumbed over many years.

A similar soil risk convinced the Washington State Department of Transportation to build a Highway 99 overpass with light Geofoam filler, and portions still sank 2 inches in 2018.

From the Stadium Station entrance, the tracks appear bowed downward, in both directions. A makeshift patch of asphalt covers an abrupt edge where the road lane meets damaged concrete in the trackway.

If rails are sagging, that indicates some risk of a future abrupt drop or failure unless crews restore them to level, Shetty said. Over the long run, trips through standing water can damage wheel assemblies, he said. And when trains brake on a slick, wet track, the sliding motion causes flat spots on the steel wheels, he said.

There are no good months to block the trackway, but the job must be done during the dry season, while concrete can cure efficiently, said spokesperson John Gallagher. This weekend was chosen, instead of earlier weeks that conflicted with Seafair, Major League Baseball All-Star Week, and packed Taylor Swift concerts, he said. Nonetheless, this weekend’s shutdown will conflict with two Mariners baseball games. August is usually one of the three busiest months.

On July 22 and 23 — when crowds of Swifties coincided with sold out Mariners-Blue Jays baseball games, the Bite of Seattle and Capitol Hill Block Party — light rail “blew the roof off” its previous record 101,000 boardings, said Gallagher, who expects to announce verified counts this week.

Passengers can sign up for text or email messages about service disruptions and reopenings at bit.ly/STrideralerts.