Problem: Road/stream crossings that are poorly designed or outdated can contribute tons of sand to a stream channel, especially with rain and snowmelt. Typical problems at road crossings include:

• Undersized culverts
• Steep approaches on dirt roads
• Old bridges and culverts that are breaking down
• Steep embankments that are not vegetated well
• Excessive foot traffic at crossings to access streams
• The culvert or bridge is the “low spot”, thus causing runoff to pool and flow directly into the stream

Culverts:
Culverts are commonly undersized to handle stream flows, and can cause big pools to form as a result.

Open Bottom Arch or Box Culvert:
Wider, longer, bottomless arch and box culverts are an ideal way to accommodate stream flows, especially during high water events.

Multiple Culverts:
Multiple culverts are not ideal as some of them can get easily blocked with branches and debris.

Bridges:
Bridges are the proper structure for crossings on larger rivers and streams.

Steep Dirt Approaches:
Steep approaches on dirt roads constantly dump sand into rivers with rain and snow melt.

Pavement and Curbing:
Pavement and curbing is the ideal way to prevent erosion of the actual roadbed into the stream.

Spillways:
Spillways with rock at the end of curbing allows runoff to filter into nearby low areas.

Check Dams:
Check dams are a series of rock piles placed in vegetated ditches that slows runoff and filters out sediment .

Run Off:
Our transportation system can be a major source of sediment to our creeks and rivers.