Scarsella Bros. Inc., of Seattle, is the apparent low bidder, with a bid of $17.3 million, for a contract to construct a 1,330-foot-long at-grade tunnel to carry Burlington Northern Santa Fe Railways tracks under the north-south freeway near Hawthorne Road.


The bid, which is one of seven submitted for the work, is $7 million less than the Washington state Department of Transportations estimate of $24.8 million for the cost of the project, which will be part of the long-planned North Spokane Corridor.


The tunnel will carry BNSFs tracks underneath the new freeway, which will cross the tracks between Piper and Hawthorne roads. Just north of there, the freeway will go over Market Street on a bridge thats already under construction.


The work will include constructing the tunnel, building and shaping a long incline that will carry the freeways northbound leg up and over the tunnel, and paving the northbound leg between Piper and where it will cross over Market, says Tom Brasch, assistant project engineer.


The freeway will come back to grade north of Parksmith Road.


The tunnel structure will be built with about 260 precast concrete arch sections, each of which will be 6 feet long. Each arch section will be made from two half-sections, each of which will weigh 21 tons. The sections will be assembled and connected to one another in a structure that will be 28 feet high and 54 feet wide, wide enough for a second track.


DOT regional spokesman Al Gilson says the contract for the work likely will be awarded in the next four weeks. He says he expects the work to be completed sometime in 2009, but the construction schedule wont be determined until the contract is awarded.