But in Taiwan, where gravel extraction and the blocking of sand flow by reservoirs upstream have created a shortage of sand along the coast leading to a loss of coastline, the only solution is to have "cultivated beaches" where people would replace as much sand as the waves carry away.
而波浪吃掉多少沙，就補回多少沙的「人工養灘法」，對於因為河川上游採沙與水庫攔沙造成海岸沙源不足、導致海岸流失的台灣，也是治本的方法。