The U.S. Army Corps of Engineers awarded a $505,000 contract to a registered small business from Wilsonville to complete several repairs to the downstream miter gate at McNary Dam.
The contract, awarded Sept. 28 to Marine Industrial Construction, LLC, involves repairs to the gudgeons (top hinge of each gate leaf), consisting of line-boring gudgeon pin bores and replacement of gudgeon pins to ensure equal loading on each gudgeon assembly. The contractor will replace bottom seal assemblies and deteriorated timber fenders on each miter gate leaf, and bumpers on the navigation lock walls adjacent to the downstream miter gate.
The lock went into service in 1953. Some of the gate components being replaced are more than 60 years old – past the end of their anticipated service life. The downstream miter gate leafs are 106 feet tall, opening and closing like a set of French doors. The lock chamber is 86 feet wide by 675 feet long with a normal operating lift of about 75 feet.
In May 2015, Corps planners announced the Columbia/Snake rivers inland navigation system will close for major rehab projects Dec. 12, 2016, through March 20, 2017. The 14-week-long closure will affect all Corps navigation locks on the Columbia and Snake rivers, with critical, major repairs, routine maintenance and improvements scheduled to occur. Ice Harbor’s lock gate machinery replacement is planned to coincide with other work to occur during the 2016-2017 extended navigation lock outage.
