It’s possible the logjam that built up against the footbridge over the Cedar River to Riverview Park started when logs chained together got stuck on the bridge supports.

Todd Black with the City of Renton Community Services Department, who arranged for the demolition company to remove the logjam, made the observation Thursday morning.

Logs chained together also were a major factor in a massive logjam under the Williams Avenue Bridge in the near-record January 2009 flooding. Those logs came from a King County installation upriver used to create fish habitat.

Black said debris has built up against the footbridge in the past but not to this degree.

Advocates for safety on the Cedar River have maintained that the logs used for such habitat or for bank stabilization are a potential risk.

Rhine Demolition of Tacoma was hired under a $20,000 contract with the City of Renton to remove the logjam. Just before noon, an excavator equipped with an 85-foot boom had pulled most of the largest logs to shore.

At the end of the boom is a rotating pincher. The excavator’s operator grabbed small logs with the pincher to push and prod the debris away from the bridge supports. They then floated downriver

A dump truck was to haul away the initial pile of large logs. Among the logs remaining was one that spanned the river – more than 100 feet long. The idea was to try to break it in half.

A crowd with cameras gathered at Riverview Park to watch the work. Renton will bring in a structural engineer to inspect the supports of what’s described as a sturdy footbridge before it reopens.

The park is still accessible from the Cedar River Trail.