Interactive Geospatial Analysis Tool for Estimating Watershed-Scale Consumptive Use: Potomac River Basin Case Study

Abstract

Human water use around the globe continues to increase while available water supplies are threatened by contamination, climate change, and aging infrastructure. Effective management of water resources is essential to ensure that water is available when and where it is needed. A necessary first step is quantifying the amount of water needed and making this information readily available to decision-makers. Specifically, information is needed on both the total amount of water withdrawn and the portion of that water which is not returned to the source, at a spatial and temporal scale that will support management decisions. Quantifying this water loss (i.e., consumptive use) is important for gauging impacts to downstream water users and to maintaining functioning ecosystems. This effort can be challenging in large basins where water use data may be collected in various formats by numerous agencies utilizing different metrics. The objective of this chapter is to present a case study model developed for the Potomac River Basin in the United States. The model consists of a basin-wide analysis and mapping tool that incorporates monthly water use data from multiple political jurisdictions, estimates consumptive water use, displays raw and summary information in an interactive geospatial format, and shares information with stakeholders via an interactive web-based mapping tool. The developed tool is expected to assist in long-term local, state, and basin-wide comprehensive water resources planning; real-time drought management; and a better understanding of human impacts on water resources.