Two tunnels soon to become one as Brightwater mining wraps up

Millions of dollars saved; contractor is recycling surplus tunnel segments

”Hiring a new contractor appears to be working out, as the new contractor is finishing more than a month early and below the established budget,” said Department of Natural Resources and Parks Director Christie True.

In February 2010, King County Executive Dow Constantine declared an emergency to hire a new contractor to keep Brightwater tunneling mining on an acceptable schedule and within budget. That spring, the County hired joint venture contractor Jay Dee Coluccio, or JDC, to complete construction on the remaining 1.9-mile segment of the four-mile BT-3 tunnel, which is being built as part of the Brightwater Treatment System project.

JDC will now prepare its tunnel boring machine, nicknamed “Elizabeth,” to make the final connection between the two tunnel segments in September. Workers are currently inside the tunnel to dismantle the remaining pieces of an idled tunnel boring machine nicknamed “Rainier.” The final step involves constructing a concrete plug that will enable “Elizabeth” to bore forward to join the tunnels.

King County originally contracted with Vinci, Parsons and Frontier-Kemper (VPFK) to build the BT-3 tunnel, but in mid-2009, the contractor’s “Rainier” machine was damaged and required time-consuming repair. Executive Constantine determined that completing the tunnel with this machine would likely result in unacceptable project delays, and made a decision to hire JDC, which had completed the adjoining four-mile tunnel and already had a machine, “Elizabeth,” in place.

Since VPFK was unwilling to complete mining of this tunnel as originally contracted, litigation is currently in process to recover all costs to King County to complete the tunnel and cover expenses from the delays.

Because “Elizabeth” was built to mine a 13-foot-diameter tunnel, the tunnel liners manufactured for “Rainier” to build a 14.4-foot-diameter tunnel that were ordered and paid for by the original contractor had to be surplused, and new tunnel segments were ordered.

While the County made it a priority to find other uses for the liners, no safe or appropriate alternative could be found.

“We looked for other projects where the liners might be reused,” said True. “We consulted with tunnel design engineers, contractors and machine manufacturers with worldwide experience. No one knew of any project where tunnel segments were successfully transferred from one project to another.

“We even looked for creative uses, such as for play structures in parks, but the concrete contains steel fibers that could cause injuries if the segments were to become chipped or damaged,” she said. “Fortunately, they can be recycled into material for roadbeds.”

JDC is scheduled to complete the tunnel connection work in September. VPFK remains under contract to complete the final tunnel liner.

The treatment plant will begin operating this summer. The public is invited to a grand opening celebration of the Brightwater Treatment System project on Sept. 24, 2011.

The Brightwater tunnel and outfall system is expected to begin transporting treated wastewater from the treatment plant to Puget Sound in August 2012.

The $1.8 billion Brightwater project is currently within 3.3 percent of its original baseline budget established in 2004, when accounting for 5 percent inflation.

According to the most recent cost trend report issued in January, the $964 million Brightwater conveyance tunnel is actually $141 million under the baseline budget established in 2004.

Note to editors and reporters: Visit the WTD Newsroom, a portal to information for the news media about the Wastewater Treatment Division, King County Department of Natural Resources and Parks: http://www.kingcounty.gov/environment/wtd/Newsroom.aspx

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People enjoy clean water and a healthy environment because of King County's wastewater treatment program. The county’s Wastewater Treatment Division protects public health, the environment and the economy by serving 17 cities, 17 local sewer districts and more than 1.5 million residents in King, Snohomish and Pierce counties. Formerly called Metro, the regional clean-water agency now operated by King County has been preventing water pollution for nearly 50 years.

Related information

Brightwater Project

King County Wastewater Treatment