Mowat Construction Company: Projects

I-5, 2nd Street Bridge Replacement

I-5, 2nd Street Bridge Replacement

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This overpass in downtown Mount Vernon had the lowest overhead clearance of any bridge on Interstate 5 between Mexico and Canada.  The two-lane structure was built in 1929 and had just 14 feet, 5 inches of clearance.  The new three-lane structure is 675 feet in length and has 18 feet, 7 inches of clearance over both north and southbound I-5, as well as crossing a set of railroad tracks and SR 536, a major state highway.   Comprised of two post tensioned cast-in-place box girder sections and one un-tensioned box girder center section the bridge was extremely difficult because it was on a significant angle to I-5.  Mowat utilized a 150 ton crane to service the bridge construction, eliminating the need for access with I-5 lane closures.  A major cost reduction incentive proposal eliminated a soil nail wall, and changed the bridge foundation from spread footings to drilled shafts.

Customer Quote: “Throughout the contract, Mowat worked with local businesses, the City of Mt. Vernon and the General Public to accommodate them with as little impact to them as possible.  They attended all Public Meetings and gave input and changed their schedule and/or method of doing work to accommodate the local community.”

“All the on site team players continually maintained safe work ethics.”

--Dave Chrisman, WSDOT Project Engineer