The purpose of this model is to calculate the likelihood of various river discharges as a function of recurrence interval and exceedence probability. This is done by employing a flood frequency analysis in GoldSim. Peak annual flow rates are obtained from a time series of historic daily average flow measurements at a measuring site located in Colorado. This model uses historic records obtained from the USGS National Water Information System (see reference below) for the Williams Fork flow gage near Parshall, Colorado. The first step is to calculate the annual peak flow rates and save these for each year of record. Next, we calculate Log Pearson III distribution parameters in the submodel "SampleData_Statistics". Using the resulting sampled distribution, we run a Monte Carlo simulation to develop the probability distribution curve that we can use to calculate return periods and exceedence probabilities.
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