Development and application of the incident command tool for drinking water protection

The Incident Command Tool for Drinking Water Protection (ICWater) provides real-time assessments of the travel and dispersion of contaminants in streams and rivers. It is structured around the RiverSpill model which has been enhanced to make use of the 1:100000 scale National Hydrography Dataset Plus, Version 1.0 (NHDPlusV1). NHDPlusV1 is a hydrologically connected river network that contains over 3 million reach segments in the United States. This allows for both downstream and upstream tracing (which serves in forensic analysis). Mean flow and velocity have been calculated by the US Geological Survey (USGS) and Environmental Protection Agency (EPA) for each reach. These mean values are updated by flow from web accessible real-time gauging stations. Example databases available within ICWater include: dams, reservoirs, water supplies, gauges, municipal and industrial dischargers and transportation networks. A contaminant database is also included which identifies biological, chemical and radiological contaminants and their toxicities. Navigating the river network upstream coupled with mass-balance calculations from breakthrough curves allows for backtracking of the contamination to determine the origin and source strength.