Theory and Practice for Safety and Stability of Check Dams

Apart from artificial factors (design standards, engineering quality, etc.), the safety and stability of the check darns in operation for building farmland is mainly affected by such three factors as: the water and sediment discharge capacity of the darns, the water and sediment retention capacity of the dams, and the water - sediment regime of the watershed. For the check darns with only two major components, not only are their water and sediment discharge capacity limited, but also the floods of identical discharge have less water depth, and their discharge capacity decreases greatly for the flood of the same frequency with constant sedimentation. When water - sediment regime in a watershed is invariable, the reservoir storage formed by the check dam will decrease at a fixed rate, i.e. linearly, due to sedimentation, while flood control capacity of the dam lowers nonlinearly with sustaining operation and reduction of storage. Slope protection can reduce water and sediment inflow significantly so that check dams have a safe operating condition, maintaining long - term stability.