In a sediment trap, what should the bottom elevation of the upstream check dam be set to?

Setting the bottom elevation of the upstream check dam to the same elevation as the top of the downstream dam is essential for effective sediment trapping. This configuration allows sediment-laden water to flow into the trap while ensuring that any sediment that does settle can remain within the trap area and not be washed over the dam into the downstream area.

By having the upstream dam set at the same elevation as the downstream dam, it creates a stable environment for the sediment to accumulate without the risk of being eroded or displaced by water flow. This design helps to enhance the sediment control function, preventing further environmental degradation due to sediment runoff.

This ensures that the sediment trap operates efficiently, maximizing its effectiveness in capturing sediments from stormwater runoff before they can enter larger water bodies, thereby contributing to better water quality and reduced erosion downstream.