HR: 1340h
AN: H13D-1539    [Abstracts]
TI: Impact of Near-Stream Ground Water Pumping on Streambed Fluxes
AU: * Su, G
EM: graces@calstarcement.com
AF: CalStar Cement, 6851 Mowry Ave, Newark, CA 94560, United States
AU: Constantz, J
EM: jconstan@usgs.gov
AF: U.S. Geological Survey, 345 Middlefield Ave, Menlo Park, CA 94025, United States
AU: Jasperse, J
EM: jay@scwa.ca.gov
AF: Sonoma County Water Agency, 404 Aviation Boulevard, Santa Rosa, CA 95403, United States
AU: Seymour, D
EM: dseymour@scwa.ca.gov
AF: Sonoma County Water Agency, 404 Aviation Boulevard, Santa Rosa, CA 95403, United States
AB: A three-dimensional, multi-phase flow model of the Russian River Bank Filtration Facility near Forestville, California was developed to investigate the impact of ground water pumping from two horizontal collector wells on the streambed fluxes and the stream-water travel times to the collector wells. Simulations were conducted at different aquifer to streambed permeability ratios. When the streambed was modeled as a homogeneous layer and the aquifer beneath was saturated, the simulations showed that the streambed velocities increased across the channel, with the largest velocities on the east bank near the collector wells. At aquifer to streambed permeability ratios ranging between 10 to 325, an unsaturated region developed below the streambed near the collector wells, which had an impact on streambed velocities. Lower velocities were observed in regions where the aquifer was desaturated below the streambed compared to the cases where the aquifer was saturated. When the total volumetric streambed fluxes were calculated at different aquifer to streambed ratios, the simulations indicated that in some cases, the streambed fluxes increased as the streambed permeability decreased. However, the stream-water residence times increased and the fraction of stream-water that reached that the wells decreased as the streambed permeability decreased, indicating that a higher streambed flux did not necessarily correlate to greater recharge of stream water around the wells.
DE: 1830 Groundwater/surface water interaction
DE: 1847 Modeling
DE: 1880 Water management (6334)
SC: Hydrology [H]
MN: 2007 Fall Meeting