Corps awards $10.5 million contract for Chittenden Locks filling gates, expect extended large chamber closures

Published Sept. 12, 2018

SEATTLE – A contract to replace the original large lock chamber’s 100-year-old filling culvert gates at the Hiram M. Chittenden Locks in Ballard was awarded by U.S. Army Corps of Engineers officials September 10, 2018.

Ferndale, Washington, headquartered IMCO received the contract award for their $10.5 million bid. The project will replace the original valves, called Stoney Gate Valves, designed and originally used during the Panama Canal construction.

President Theodore Roosevelt initially appointed seasoned railroad builders to lead the canal construction project along the Panamanian Isthmus in 1904. However, in April of 1907, he transferred supervision to a group of U.S. Army Corps of Engineers officers and civilians. In 1910, about the time Seattle Corps of Engineers received funding to build the Chittenden Locks, installation of the Stoney Gate Valves began in Panama. The same system made its way into Seattle’s project. The Panama Canals gate valves were replaced several years ago.

“The valves have been well maintained over the last 100 years,” said Operations Project Manager Jon Hofstra. “Although, it’s time. They’re past the life expectance of this type of equipment and the salt-water environment has taken its toll as well.”

This is a major component of the Locks and to replace those means lengthy outages, according to Hofstra.

“Beginning in 2019 we’ll start the first of four 45-day outages to replace the gates,” said Hofstra. “We know this will affect our commercial users quite a bit, but in the long run it means a more reliable lock system and less chance of an extended outage.”

The current extended outage schedule is:

2019 –   October 12 through November 30

2020 –   February 12 through April 2

              October 12 through November 30

2021 –   February 12 through April 2

The regular annual lock maintenance closure is expected to return in fall 2021, currently set for November 9 through 24. This year the large chamber will also see seven days of additional closure time beginning October 29 and ending November 21. During this additional time a contractor will replace the large lock center gate bushings and gudgeon pin. These components support the weight of the gates, allowing the heavy gates to rotate open and closed during normal gate operations.

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Bill Dowell

Release no. 18-060