Proposal for Safer Construction in Rivers

Common Risks in Northwest Rivers

Large Woody Debris (LWD) installation on the Cedar River east of Renton.

Rivers everywhere contain naturally occurring hazards that require river users to possess skill and knowledge to avoid, and the judgment to know when the risk is too great.

However, man-made obstacles are increasingly being built in rivers and streams for many purposes. They may be designed to facilitate fish habitat, capture of hatchery stock, irrigation, or for purposes such as highway or bridge structures. These obstacles may be constructed without warning, with little or no clear signage or notice to local residents or river users, and with inadequate thought to the effect on river users.

Unlike naturally occurring hazards, man-made structures can be constructed such that they may survive in high velocity, turbulent, or constricted parts of the river where naturally occurring debris might not. When man-made obstacles containing sharp projections and sieve-like features are constructed in technically challenging unnatural portions of the stream bed, or in areas used by inexperienced people, the hazard to river users can be extreme.

Safety Guidelines

The River Safety Council has developed clear information about these structures and a recommended process for minimizing and mitigating the hazards they create.

LWDSafetyGuidelines.pdf