- Branches, logs, crop residue, sediment, and rocks can accumulate in spillway outlets.
- Reduced discharge capacity will cause the reservoir to rise and possibly overtop the dam. Prolonged overtopping can cause dam failure.
- Trees, hay bales, fences, and farm equipment are all common obstructions to flow in auxiliary spillways.
- Fence lines in auxiliary spillways can catch debris and become a major obstruction to flow.
- Obstructions reduce auxiliary spillway capacity and cause scouring and erosion to develop.
- Inspect spillways after large flood events.
- Remove debris in or around spillway outlets.
- Use extreme caution when attempting to remove accumulated debris during periods of high flow.
- Keep your distance when removing debris so that you don’t become trapped in flowing water when the flow increases after you remove the debris.
- Do not allow trees to grow in the auxiliary spillway. Remove trees and other brush annually. Treat the stumps of deciduous trees with herbicide to prevent regrowth.
- Do not store equipment or materials in the auxiliary spillway.
- Relocate fence lines so they do not pass through the auxiliary spillway.