See more from this Division: Topical Sessions
See more from this Session: Advances in Surface Water–Groundwater Interactions: Investigations of Rivers, Lakes, and Wetlands
Abstract:
Seepage meter measurements show that larger, more central reservoirs generally act as groundwater discharge zones, with seepage losses to groundwater occurring only in regions close to the dam. Smaller hillslope reservoirs generally act as zones of focused infiltration throughout, with few areas of groundwater discharge. Isotopic analyses show that water taken from both wells and boreholes downstream of reservoirs is enriched in heavier isotopes while samples taken at points upgradient of reservoirs have the same signature as rainwater. These results indicate that hillslope reservoirs act as zones of focused recharge and thus could affect downgradient groundwater quality. A numerical model of groundwater flow, calibrated using observed water levels and transmissivity estimates, provides further constraints on the magnitude of reservoir/groundwater exchange.
See more from this Division: Topical Sessions
See more from this Session: Advances in Surface Water–Groundwater Interactions: Investigations of Rivers, Lakes, and Wetlands