ITD highlights complexity of U.S. 95 bypass

PONDERAY - The complexity of constructing the U.S. Highway 95 bypass on the buoyant land mass that is Sandpoint was underscored during an Idaho Transportation Department presentation on Thursday.

"Sandpoint floats. There's nothing under Sandpoint," Ken Sorensen, ITD's resident engineer, told members of the Ponderay Economic Development Corp.

As a result, settlement will be a force to contend with when the proposed Sand Creek Byway's eight main structures, and the nine miles of pile to hold them up, are installed.

Sorensen said test piles near the north end of the Long Bridge had to be driven 160 feet before they stopped settling on their own.

To lessen the amount of time needed for the various structures to settle, Sorensen said fills and the 65 retaining walls scattered among 20 locations will be pre-loaded and allowed to sit for months. More than 2,460 feet of wick drains will be installed to hasten the settlement process, according to Sorensen.

The soil-consolidating wick drains increase settlement rates.

The bypass project will be divided into fourths, although Sorensen was unable to say how construction of the individual segments will be sequenced. Parsons RCI, the Washington state company awarded the project's $98 million construction contract, is slated to meet with ITD behind closed doors in the coming weeks to go over how construction timing and traffic will be handled.

Parsons will submit its construction plan to ITD for approval, according to Barbara Babic, ITD's Panhandle spokeswoman. During construction, weekly public meetings will be held to advise people what construction is in store for the week ahead. A Web site is also being planned.

Regardless of the construction plan, Sorensen said there will be traffic bottlenecks and delays at the north end of the Long Bridge and in the vicinity of the U.S. 95/Highway 200 junction.

Much of the project's construction timing will be dictated by regulatory windows established to protect wildlife and environmental resources.

"There's not a day on this job without one restriction or another," said Sorensen.

The transportation department also operates under a consent decree prohibiting construction during winter months, but Sorensen said ITD will seek permission to work then because of the fluctuating level of Lake Pend Oreille.

Sorensen said the entire bypass is either being built adjacent to or in water, and that the construction will be high-profile.

"It's going to be built in a fishbowl. A lot of people are going to be watching us," he said.