Seasonal O variations in precipitation, soil water, snowmelt, spring flow and stream baseflow were analyzed to characterize seasonal dynamics of groundwater recharge in three central Pennsylvania catchments. The catchments represented three common landscape types: Valley and Ridge-shale (Mahantango Creek), Valley and Ridge-carbonate (Buffalo Run), and Appalachian Plateau-sandstone (Benner Run)....

This paper presents a methodology for the design and optimization of artificial recharge-pumping systems (ARPS). The objective of ARPS is to provide a maximum abstraction rate through artificial recharge, while meeting two operational constraints: (a) the influences of the system operation on groundwater levels should be no more than 25 mm in the vicinity of the system; and (b) the travel time ...

The El Niño-Southern Oscillation (ENSO) is an interannual phenomenon involved the tropical Pacific Ocean-atmosphere interactions. The oscillatory nature of ENSO requires both positive and negative ocean-atmosphere feedbacks. The positive feedback is dated back to Bjerknes' hypothesis in the 1960s, and different negative feedbacks have been proposed since the 1980s associated with the delayed os...

The reuse of treated wastewater for groundwater recharge is an effective way to provide advanced treatment and water storage. Contaminants such as human drugs have been identified as a potential problem for use of this water. Gilbert, Arizona maintains a 28.3-ha facility designed to recharge 15,150 m d through recharge basins constructed on native soil. The facility averages an infiltration rat...

Hydrologic analyses are commonly based on a single conceptual model. Yet hydrologic environments are open and complex, rendering them prone to multiple interpretations and conceptualizations. Considering conceptual model uncertainty is a critical process for the assessment of hydrologic uncertainty. This study assesses recharge and geologic model uncertainty for the Climax Mine area of the Neva...

The Northern Guam Lens Aquifer (NGLA) presents unique challenges to modelers due to the complex hydrologic properties of its thick karst vadose zone. To meet these challenges, we developed VADOCHARGE, an analogue model based on the US Army Corps of Engineers’ Streamflow Synthesis and Reservoir Regulation (SSARR) model, to produce the effect of attenuated and lagged recharge through the vadose z...

The agriculturally productive San Joaquin Valley faces two severe hydrologic issues: persistent groundwater overdraft and flooding risks. Capturing flood flows for groundwater recharge could help address both of these issues, yet flood flow frequency, duration, and magnitude vary greatly as upstream reservoir releases are affected by snowpack, precipitation type, reservoir volume, and flood ris...

Water scarcity contributes to the poverty of around one-third of the world's people. Despite many benefits, tree planting in dry regions is often discouraged by concerns that trees reduce water availability. Yet relevant studies from the tropics are scarce, and the impacts of intermediate tree cover remain unexplored. We developed and tested an optimum tree cover theory in which groundwater rec...

Implementation of aquifer storage recovery (ASR) for water resource management in Florida is impeded by arsenic mobilization. Arsenic, released by pyrite oxidation during the recharge phase, sometimes results in groundwater concentrations that exceed the 10 µg/L criterion defined in the Safe Drinking Water Act. ASR was proposed as a major storage component for the Comprehensive Everglades Resto...