HEC-1套裝程式應用之便利在於僅需將輸入之數據,依照規定編排之方式,卽可從事運算而得需要之結果;然就數據輸入而論,美國之水文觀測記錄甚久,且經觀測人員隨時計算整理繪製圖表,再經由美國農林部(負責美國河流上游之集水區)及地質調查所(負責河流中下游之流域)分別編排整理,印製年報每年100册(美國共50州,每州河流之上游一册,中下游一册),內容廣泛而遇密;如使用HEC-1程式時之暴雨歷線、洪水流量歷線、降雨延時曲線、面積雨量曲線及標準降雨分配曲線等,均可直接或間接依據上述圖表、歷線或曲線轉換爲對應之數據,輸入程式,卽可求得所需之結果,使用便捷。反觀本省之水文記錄及水資源委員會出版之水文年報,對於HEC-1而言均不可直接應用,而必需加以整理與轉換,故對程式之內容結構須有相當程度之了解與分析,否則實難套用此程式而獲便捷之效。依據HEC-1使用手册可以歸納其功能有以下八項:一、河溪網流模式(stream network model)。二、降雨逕流模擬(rainfall runoff simulation)。三、水文參數推定(parameter calibration)。四、複計畫複洪水流量分析(multiplan-multiflood analysis)。五、水壩安全分析(dam safety analysis)。六、雨量~面積關係計算(precipitation depth-area relationship)。七、洪水災害分析(flood damage analysis)。八、防災系統最佳化研究(flood control system optimization)。依據上述目的之不同,可自HEC-1程式中删减若干不必要之程式,以減少佔用電腦中之記憶容量,簡化繁複之計算。針對目前本省水文觀測記錄現況,作者將HEC-1程式修正與簡化,概括上述HEC-1之前四項及第六項,而此程式則具備有以下五項功能:一、集水區降雨逕流歷線演算。二、合成單位歷線(而HEC-1程式則係應用Clark法之合成單位歷線)。三、洪水流量演算(採用下述五種方法)。四、水文參數計算(包括入滲曲線、合成單位歷線、退水曲線以及河道演算參數等項)。五、複站洪水流量分析。第五項之複站洪水流量分析過程卽包括上述之一項至四項,同時對此一新程式之功能與應用,作一比較之研究與檢討;圖(1)卽爲複站洪水流量分析程式設計之流程圖。
The HEC programs package have been developed by Hydrologic Engineering Center of US Army Corps of Engineers, to support the advantage about hydrologic routing, parameter estimation and optimal design. For more generally and applicatively to HEC-1 program in Taiwan, the new program for simplification and modification of HEC-1 is submitted. This new program supplies these work about rainfall-runoff simulation, synthetic unit hydrograph estimation, flood routing, hydrologic parameter estimation and multiple station flood analysis. Into rainfall-runoff simulation, this new program involving φ-index average infiltration method is comparied with infiltrative curve method of HEC-1 program in example running. For flood routing, there are four methods HEC-1 involved, which are Muskingum method, S-S method, modified Puls method and multiple storage method. In addition to these four methods, the working-value method is introduced. For example running, flood-design informations of Housationic basin are taken into count, these results are plotted as flood hydrographs by CALCOMP plotter.