Statewide Water Supply Planning: Addressing Future Uncertainties with Flexible Watershed Assessments

The Oklahoma Water Resources Board (OWRB) has initiated a major update of the Oklahoma Comprehensive Water Plan (OCWP) through a unique federal/state partnership with the United States Army Corps of Engineers (USACE). Scheduled for completion in 2012, the OCWP is assessing the physical and legal availability of Oklahoma's surface and groundwater resources, all in the context of water quality and infrastructure constraints, to meet the state's needs through 2060. The forecasted demands are being compared to physically and legally available supplies using the Oklahoma H₂O tool, a first-of-its-kind analysis tool that interactively assesses the potential for future water shortages on both a statewide and watershed level. Using a customized Microsoft Access interface, together with geographic information systems (GIS), the Oklahoma H₂O tool provides unprecedented analysis power in evaluating potential future "what-if" scenarios and potential solutions for meeting the state's water needs for the next 50 years. It has been used to quickly test alternative solutions brought forth through the OCWP's public input process and serves as the foundation for regional supply assessments and basin-level water plans. By adopting a continuous planning process, Oklahoma is adaptively managing its water resources on a basin-by-basin level. This process provides for careful consideration of anticipated future conditions while mitigating against the uncertainties in supply and demand that climate change, land use practices, and other future influences will bring.