The City of Renton has asked King County to pay for the cost of removing a logjam late last week against the footbridge over the Cedar River to Riverview Park.

The city hired a contractor under a $20,000 contract to pull some logs from the river and let other logs and debris float freely down the Cedar River.

The work was done Thursday; the bridge was reopened Monday after an inspection showed it had suffered no damage, other than some scratches.

In removing the logs, the city discovered some were chained together, a sign they likely came from a King County project upriver at Cedar Rapids designed to stabilize a levee and provide fish habitat.

On Monday, the city sent a letter to county officials asking that the county pay for the logjam removal. The city also provided three other sites where chained logs have been found and asked that those be removed, said Ron Straka, the city’s surface water utility supervisor.

Clint Loper, a supervising engineer for King County Rivers, said Tuesday the county was considering Renton’s request for payment. He said it’s “highly probable” the logs against the footbridge originated at Cedar Rapids.

County maintenance crews Tuesday found the logs on Renton’s list and cut the chains, said Loper, although he said he only receive two locations from Renton. The logs remained in the river, as required by the state fisheries department, he said.

“They are being very responsive,” Straka said. Renton also asked that crews look for other county logs, too.

Chained logs were also one of the causes of a logjam that built up against the Williams Avenue Bridge in downtown Renton during the near-record flooding of January 2009. The county paid to remove that logjam, once it was determined the logs came from the Cedar Rapids project.

The logs were installed at Cedar Rapids in 2008, anchored by large rocks. Some also were anchored to trees, Loper said. During the 2009 flood, the logs “moved away” from the project site, Loper said.

“They turned out to not be as stable as they should have been,” he said. Logs were removed in 2009, he said.

Now the county is anchoring such logs to deep pilings, he said, which can withstand the river’s force, unlike large rocks. The logs will remain chained.