SCS-CN Hydrologic Modeling of the Great Dismal Swamp with HEC-HMS




Larson, Timothy R

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The simulation of surface runoff at the Great Dismal Swamp National Wildlife Refuge, located in southeast Virginia and northeast North Carolina, is modeled on a digital elevation model (DEM) with 2 meter post spacing. An application of the Soil Conservation Service Curve Number (SCS-CN) hydrological model as implemented through the Hydrologic Engineering Center’s Hydrologic Modeling System (HEC-HMS) is used to predict how the basin might respond to rainfall events, including measures of the quantity of surface runoff, detention, and peak runoff. Validation of the model is conducted by comparing results to streamgage readings at the swamp. Accuracy is greatly limited by an unknown configuration of water control structures at the swamp and programmed outflow through a lock and dam system. But a detailed configuration of streams and watershed units is achieved.



SCS CN, Great Dismal Swamp, Runoff, HEC_HMS