HR: 1340h
AN: H33D-1621    [Abstracts]
TI: Determining Seasonal Recharge to the Treasure Valley, ID using Dissolved Noble Gas Data
AU: * Thoma, M J
EM: michaelthoma@mail.boisestate.edu
AF: Department of Geosciences Boise State University, 1910 University Dr., Boise, ID 83725, United States
AU: McNamara, J P
EM: jmcnamara@mail.boisestate.edu
AF: Department of Geosciences Boise State University, 1910 University Dr., Boise, ID 83725, United States
AB: Recent municipal development and urban sprawl has placed strong stresses on regional groundwater systems, especially in western United States basin areas. Understanding of groundwater systems and fluxes is important for assessing the need for future water conservation practices. Quantifying these fluxes, however, has often been done by conceptual modeling or chemical mixing data, which supplies recharge origin, but not a well defined location. The use of noble gas concentrations to determine infiltration temperature and, comparing with the local lapse rate, elevation, has become very useful in these types of problems. Sampling of basin wells along with mountain front springs was done to determine the recharge source to the Treasure Valley Aquifer. Results have shown a distinct separation between mountain block infiltration and basin floor infiltration, evident in the spatial distribution of recharge temperature within the basin wells. This data confirmed previous work showing that a substantial portion of recharge to the northeast part of the Treasure Valley is the result of mountain block recharge and further delineates the spatial extent of influence by mountain block recharge into the basin. This data also highlights the importance of seasonally biased recharge both within the mountain block (spring snow melt) and at the basin floor (summer irrigation).
DE: 1832 Groundwater transport
DE: 1876 Water budgets
SC: Hydrology [H]
MN: 2007 Fall Meeting