What function does an anti-seep collar serve in a principal spillway?

An anti-seep collar serves an essential function in a principal spillway by preventing water from traveling along the barrel pipe. This collar is typically installed around the pipe and is designed to restrict the flow of water that might seep through the soil surrounding the spillway. When water seeps along the pipe, it can erode the soil around it, which may lead to instability or even failure of the dam. By blocking this flow, the anti-seep collar helps to maintain the integrity of the structure, ensuring that water is properly directed through the spillway and reducing the risk of erosion and potential dam failure. This function is particularly critical in maintaining the overall safety and reliability of a dam, highlighting the importance of proper design and installation of components like the anti-seep collar in stormwater management systems.