Coupling of Atmospheric Deposition, Surface Runoff, and River Transport Models for Drinking Water Protection and Homeland Security

Surface runoff of contaminants has been included as a source term in the Incident Command Tool for Drinking Water Protection (ICWater). This allows for modeling of chemical/biological/radiological contamination resulting from atmospheric deposition or direct application to the watershed. ICWater is a network-based toxic spill model that calculates time-of-travel and concentration of contaminants based on real-time stream flow data. The work described in this paper couples ICWater with: (1) a methodology for determining surface runoff of contaminants and (2) the Hazard Prediction and Assessment Capability (HPAC) model which calculates atmospheric deposition. The coupled models are operationally functional for all of the U.S. The Geospatial Stream Flow Model (GeoSFM) is being coupled with HPAC for application to areas outside the U.S. where ICWater does not apply.