BONNEVILLE, Oregon — River traffic on the Columbia River is at a standstill until a broken sill in the lock at Bonneville Dam gets fixed.

Engineers first noticed the problem in early September when water levels wouldn't stay constant. The lock was drained and a crack in a concrete sill was detected. Engineers immediately closed down all river traffic access and addressed the problem.

"Bonneville Navigation Lock is one of the last locks along the Columbia River. With this being closed down, it is essentially an entire stop to the Columbia River and all the commerce on it," said Kerry Solan, spokesperson for the U.S. Army Corps of Engineers.

A closure at the dam is normal. Every five years it's shut down for inspections, and every spring it's closed for maintenance. The damage to the sill, which caused the recent emergency shutdown, is unusual.

This is all taking place as the grain harvest is in full swing. The Columbia River is the number one waterway used to export grain, and Washington and Oregon are among the leading states to produce wheat in the U.S.

"It makes it tough on logistics for sure. It's better that it happened now than right in the middle of harvest, July or August," said Jason Middleton, Pacific Northwest regional manager for the United Grain Corporation.

The sill acts as a seal when the huge doors inside the lock close, keeping the water in. A lock is used to move ships, barges and other boats from one side of the dam to the other. Water in the lock rises and lowers depending on which direction the traffic is headed.

Lock damage
Pat Dooris

The broken sill first had to be demolished before work on the new one could start.

The Army Corps of Engineers says the work should be completed by September 30th.

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