Chesapeake Bay Program Watershed Model Scenario Output Database

The model divides the 64,000 square mile Chesapeake Bay drainage basin into 87 model segments. Each segment contains information generated by a hydrologic submodel, a nonpoint source submodel, and a river submodel.

The hydrologic submodel uses rainfall, evaporation, and meteorological data to calculate runoff and subsurface flow for all the basin land uses including forest, agricultural lands, and urban lands. The surface and sub surface flows ultimately drive the nonpoint source submodel, which simulates soil erosion and the pollutant loads from the land to the rivers. The river submodel simulates flow and associated pollutant loads from the land through the lakes, rivers, and reservoirs to the Bay.