Applied Math Seminar: Hydrogeological Modeling of the Pullman-Moscow Basin Basalt Aquifer System, WA and ID
3:10 PM, Webster B8
Abstract: Ground-water management in the bi-state Pullman-Moscow area is facing an impending problem of continuous, steady decline in water levels in the basaltic Palouse Basin Aquifer system (PBA). The ultimate goal of this study was to develop an improved basin-scale ground-water flow model as a management tool. Major wells within the study domain were digitized and included in the hydrogeology GIS database. Long-term ground-water hydrographs were developed and the relationships between ground-water level, annual precipitation and pumpage were evaluated. Structural maps for the two basalt aquifers were constructed, and potentiometric surface contour maps for different times were created. Previous ground-water models for this region have assumed simplified, "layer-cake" type of basalt system, and uniform aquifer hydraulic properties. The comprehensive hydrogeological information compiled and analyzed in this study suggested that the PBA system is largely governed by highly complex geological structures and spatially varying recharge and discharge mechanisms, aquifer geometric configurations and hydraulic properties. This information is crucial for developing the new model suitable for ground-water resource management in the basin.