可能最大洪水不一定必须大于万年一遇洪水

本文就可能最大洪水（ＰＭＦ）是否必须大于万年一遇的洪水（ＲＴＦ）作了全面的分析。从抽象的概念出发，ＰＭＦ大于ＲＴＦ无可非议，但是限于当前的水文资料条件和水文科学水平，ＰＭＦ和ＲＴＦ的估值中包含有很大的误差．因此就实际的估值而言，二者孰大孰小难以定论。硬性规定ＰＭＦ必须大于ＲＴＦ并不恰当。

Must Probable Maximun Flood be Larger Than the Design Flood With Recurrence Interval of the Thousand Years

The comprehinsive analysis in the relstionship between probable maximum flood (PMF) and the design flood with, recurrence interval of ten thousand years (RTF) has been performed in this peper. From the point of view of PMF and RTF concepts the former should be undoubtedly larger than the latter. The estimators of PMF and RTF have gross errors due to the limit of hydrological data and deficiency of hydrological science. Therefore, the estimator of PMF are not definitely larger than that of RTF. In the standard of design flood the stipulation that PMF must be larger than RTF would not be appropriate because only their estimators are encountered in hydrological computation.