Debris Rack and Deflectors

What – A debris rack is a structure placed across a stream channel to collect debris before it reaches a culvert entrance.  A debris deflector is a structure (usually V-shaped with apex pointed upstream) placed at the culvert inlet to route the major portion of debris away from the culvert entrance.

Purpose – Designed to protect culverts from catastrophic failure by catching floatable debris that otherwise would likely plug culverts and cause stream diversion.  By protecting culverts from failing, these structures protect transportation infrastructure, public safety, and downstream resource values.

Effectiveness – No quantitative data exists on the effectiveness of debris structures.  However, anecdotal information indicates they can be effective with proper implementation and maintenance.  Problems can occur if the design structure is too small for the stormflows and associated debris.

Where

• Culverts at risk of plugging with debris.
• Where downstream infrastructure, public safety, or other resources are at risk.

Cost – $100–4000 depending on material.  Log racks built with onsite burned logs are economically efficient.  Structures constructed with heavy rail or steel range from $3000 to $30,000 or more depending on the size and materials required.  Additional factors include:

• Site location and access
• Materials required for implementation
• Number of structures

How to Link – See USDA BAER Catalog page 134 (PDF page 142).