Use materials that are clean, nonerodible, and nontoxic. To prevent erosion and under-cutting of the inlet end of the culvert, provide a headwall. Keep culverts clear and free of debris so water can pass unimpeded at all times. Culvert failure is caused by blockage with debris as often as by the culvert's capacity being exceeded. For this reason, avoid leaving excess amounts of woody debris in stream channels where it can float downstream and lodge in culverts.
Maintenance is especially important in areas where beavers are present.
Undersized culverts can become plugged with sediment A culvert not installed at the existing stream gradient can degrade the stream channel. Install riprap to prevent erosion at the inlet to a culvert pipe. The streambed has a firm rock or coarse gravel bottom, and the approaches are low and stable enough to support traffic. Traffic is limited to low volumes of light vehicles. Water depth is less than 3 feet.