确定防洪堤设计水位的方法探讨

Probing into the method for determination of the design water level of flood embankment

应采用各种洪水年型都包得住的水位作为防洪设计水位才是安全的，否则就会出现水位达到了历年最高，可流量还远未达到；或流量达到了设计频率而相应水位达不到设计值；筑堤洪水归槽，水位壅高，防洪水位还要加上壅高值。因此，河道上的防洪水位确定是很复杂的。由年最大水深计算频率求设计水位和由年最大流量频率值求设计水位，但都要采用外包线上限值；为此，提出４ 种计算筑堤后洪水归槽水位壅高的方法。

The determinating of flood proofing design water level of river is very complex.It's safety only that the design water level must include various flood year patterns.The authors suggest four calculating methods for flood returning channel and water level rising after constructing embankment.