Purpose and Objectives

The purpose of this project is to provide a scientific foundation for management of the SVRP aquifer. The study will culminate in the development of a numerical ground-water model that Washington and Idaho can use to cooperatively manage the SVRP aquifer and adjacent rivers and lakes.

Specific objectives include the following:

1. Aquifer Characterization - Delineate the extent and thickness of the SVRP aquifer, determine aquifer boundary conditions, and document the spatial distribution of aquifer hydraulic properties.
2. Hydrologic Data Collection - Measure ground-water levels and streamflows, and quantify recharge rates to the aquifer from precipitation and evapotranspiration losses.
3. Water Use - Quantify the spatial and temporal distribution of aquifer and river withdrawals for municipal, commercial, industrial, domestic, and irrigation usage.
4. Water Quality - Define current ground and surface water quality characteristics.
5. Ground-Water Surface-Water Interactions - Delineate gaining and losing reaches of the Spokane and Little Spokane Rivers, and quantify the seasonal exchange of ground and surface water. Quantify losses from lakes that are in hydraulic connection with the aquifer.
6. Numerical Model - Construct a numerical model representing the current understanding of aquifer flow characteristics. Calibrate the model to steady-state and transient hydraulic conditions on the basis of current and historical data using automated parameter estimation methods that enable quantification of parameter uncertainty.
7. Model Application - Use the numerical model to (a) analyze aquifer inflows and outflows, (b) analyze alternative flow characteristic conceptualizations, (c) simulate responses to unit aquifer withdrawals, (d) simulate aggregate effects of future increased aquifer withdrawals, and (e) evaluate selected aquifer management scenarios.
8. Public Involvement - Convey information about regional water resources and knowledge gained from the study to federal, state and local decision-makers, the professional community, and the general public through published reports and public meetings.

Estimated Total Project Cost $3,500,000