Summary

The goal of this study was to identify whether the development of an open area in the CRS watershed increased runoff, and if so, how much. Using available watershed data and computer program HEC-HMS, the analyst was able to answer the questions. As shown in the HEC-HMS Results at Arden Way for 0.01 AEP Event table, the development does increase the peak runoff and total volume of runoff. If the development is to be permitted, some water control features must be included to reduce the peak for the 0.01 AEP storm from 1,003 cfs to 941 cfs. There are many options available for reducing the flood peak and flood damage. Some of these options and how they are modeled using HEC-HMS are discussed in the Flood-Loss Reduction Studies.