HEC-HMS 4.2.1 Model for Rapidan River Watershed, VA

HEC-HMS 4.2.1 can be used to accurately route stream flow through a selected watershed. A model of the Rapidan River Watershed, VA was calibrated using a precipitation event occurring on April 2nd, 2005 at 15:00PM. The baseflow method chosen was the recession method and Muskingum routing was used as a routing method. Optimization trials were used once the model closely resembled the observed precipitation event. Model accuracy was determined by the Nash-Sutcliffe model efficiency coefficient and Peak Volume of discharge, before testing the model with additional precipitation events of similar size and seasonal occurrence. Peak discharge volume was unable to match the observed data for additional storms. The model was able to predict the time of peak discharge with accuracy, all three storm peaks reported within 15 minutes of observed data. Since this model was able to accurately predict the time of the peak discharge, it is still possible to use this model for temporal flow routing through the Rapidan River Watershed. It would not be accurate to use this model to quantify the amount of discharge occurring during a precipitation event.

HEC-HMS 4.2.1版本能够精确地模拟选定流域的径流路径。以弗吉尼亚州 Rapidan 河流域为模型，采用2005年4月2日15:00发生的降水事件进行校准。选用的基流方法为退水法，而水力路由则采用 Muskingum 方法。模型与观测降水事件高度相似后，进行了优化试验。模型的准确性通过纳什-萨特克利夫效率系数和峰值流量确定，在测试模型与相似规模和季节性发生的额外降水事件之前。对于额外风暴，峰值流量无法与观测数据匹配。模型能够准确预测峰值流量的时间，三次风暴峰值均报告在观测数据15分钟之内。鉴于该模型能够准确预测峰值流出的时间，仍有使用该模型进行 Rapidan 河流域时空径流路径模拟的可能性。然而，使用此模型来量化降水事件中发生的流量量级则并不准确。