Sound Transit tunnel bids are cheaper than predicted

Two bidders on a Sound Transit tunneling contract are offering to do the job much cheaper than predicted by the agency's engineers — a potential savings for the University Link line from downtown Seattle to Husky Stadium.

The bids were opened Wednesday. The lowest is $309 million by the Traylor Frontier-Kemper Joint Venture, some $86 million less than the $395 million Sound Transit estimate, said transit spokesman Bruce Gray. The other bid is $360 million, from the JCM U-Link Joint Venture.

The winner will burrow twin tunnels for two miles between the stadium and Capitol Hill, where old buildings are already being demolished at the future station site. This is the fifth and biggest of 11 contracts along the $1.9 billion line, to open by 2016.

A slumping economy has caused contractors to reduce prices on a number of public-works jobs, at the same time technology has improved in the tunneling industry.

"We are pleased with the response of the contracting community as well as the favorable results today," light-rail Director Ahmad Fazel said in a statement. A cautionary note: Five years ago, a nervous-looking Fazel opened a lone bid for the Beacon Hill Tunnel that exceeded the $239 million estimate, at $280 million. Costs rose during construction and are currently at least $303 million, with a few months remaining. The line from Westlake Center to Tukwila is set to open in July.

On a surface segment in Rainier Valley, the agency celebrated a low bid, only to see costs rise back up to the earlier estimate.

Sound Transit has learned from experience, said Gray. For instance, U-Link project was designed with two relatively shallow stations, unlike the 165-foot-deep station in Beacon Hill, where mining led to soil slides and delays.

A separate contract will be signed for the tunnel segment from Capitol Hill to downtown, spreading the cost risk. "We've worked as hard as we can to take out as many surprises as possible," Gray said.

Because of the high chance of cost overruns, Sound Transit earlier dropped its deep station at First Hill, part of the route voters approved in 1996.

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