Advertising

The Seattle Times Company

NWjobs | NWautos | NWhomes | NWsource | Free Classifieds | seattletimes.com

Local News


Our network sites seattletimes.com | Advanced

Go to the politics section for more local and national politics coverage.

Politics Northwest

The Seattle Times political team explores national, state and local politics.

January 31, 2011 at 3:22 PM

Comments (0)     E-mail E-mail article      Print Print      Share Share

Tunnel update: It's becoming less risky, says City Council consultant

Posted by Mike Lindblom


The winning construction bidders for the Highway 99 tunnel offered protections for the public beyond what the state required, according to John Newby, the City Council's consultant about the project's financial risks.

Newby gave his viewpoint in an update Monday, along with this presentation.

However, the financing side still contains gaps: the Port of Seattle hasn't explained where it will get the $300 million it pledged, nor has the state decided how to raise $400 million in tolls. The tunnel accounts for $2 billion of the overall $3.1 billion highway corridor project to replace the Alaskan Way Viaduct, which has survived nearly 10 years since the Nisqually earthquake.

The state Department of Transportation signed a $1.4 billion contract Jan. 6 with Seattle Tunnel Partners (STP), a consortium led by Dragados of Spain and Tutor-Perini of California. Newby said one encouraging feature is the plan to insert vertical walls of concrete piles, as well as shallow horizontal beams, to stabilize the tunnel route near the sports stadiums and old Viaduct, forming a sort of "box" just before a giant boring machine drills the 57.4-foot-diameter hole. Another positive, Newby said, is that STP is preparing to deal with weaker soil and higher ground water pressures than what the state's geotechnical report found.

Mike O'Brien, the council's only tunnel opponent, asked why citizens should rely on DOT assurances in light of the Highway 18 widening project, where a state auditor's report found "a gross waste of public funds" as costs nearly doubled. Ron Paananen, Highway 99 administrator, said the Highway 18 project through slopes and wetlands, in the mid-2000s, was "from an environmental point of view, a much bigger project than this one," and DOT has learned from mistakes there.

Newby took comfort that when Sound Transit's Beacon Hill light-rail tunnel caused several voids, those required only $4 million to fill, while DOT has $100 million to tackle unexpected tunnel problems.

An obvious question is, wouldn't the costs be far worse if soil gaps form under a downtown filled with towers?

"It might be more complicated," he said after the council session. But he said the risk is offset because DOT and its contractors will keep better track of removed soil, and blanket the route with instruments to spot any ground sinkage or gaps early. The technologies include lasers to measure soil as the cylindrical tunnel machine expels it via conveyor belt. It's a priority, given what's happened on Beacon Hill, and the sensitivity of [downtown] structures," he said.

Another angle that came up Monday was the contractors' $500 million insurance policy, required by DOT. The figure could be viewed as both a safeguard and an indicator of the high stakes. O'Brien didn't get an answer from officials when he asked which crisis scenario might trigger a $500 million loss.

Overall, Newby said, the remaining tunnel contingency -- the $100 million plus $60 million in allowances for soil settlement and emergency repairs underground at the face of the tunnel machine, are near the top end of the range for such projects, and adequate here.

Meanwhile, the anti-tunnel Initiative 101 campaign plans to file 28,000 petition signatures Tuesday morning at the city clerk's office, said I-101 supporter Christopher Brown. A total 20,629 valid signatures are needed to qualify for a possible May vote. The measure seeks to prohibit use of city right-of-way for tunnel construction.

Another campaign just underway, I-102, calls for extra financial oversight, and is aimed at putting pressure on pro-tunnel incumbents this November. "One way or another, our voice will be heard. You better start listening," spokesman Drew Paxton, a local Sierra Club activist, told the council.

Mayor Mike McGinn, who has criticized the tunnel's potential for cost overruns and carbon pollution, is expected to comment Tuesday.

Just before Newby's review, union members in hardhats filled most of the council chamber as business and labor officials made pro-tunnel comments. "For those who say we can never get things done ... your steady and adult leadership culminating in this ordinance demonstrates that we can," said Tayloe Washburn, former Greater Seattle Chamber of Commerce chairman. The council is scheduled to approve utility and land-use agreements with DOT next Monday, as design proceeds toward a possible August groundbreaking.

E-mail E-mail article      Print Print      Share Share

News where, when and how you want it

Email Icon

Comments
No comments have been posted to this article.