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Riparian and wet meadow ecosystems are a critical ecological and human resource throughout the Great Basin.� Understanding the controls on surface and subsurface water is an essential component in evaluating the resilience of stream and groundwater dependent ecosystems and determining effective management strategies. Our prior research on 56 riparian wet meadows in central Nevada indicates that meadows occur in groundwater discharge zones with high groundwater tables.� These types of areas occur where geologic conditions have created significant sediment deposits that include fine-grained materials, for example, areas upstream of side-valley alluvial fans.� Wet meadows require high groundwater tables and can form independently of streams, but they are threatened by stream erosion.� Stream incision lowers groundwater tables and new stream channels can cut through stratigraphic units essential to supporting high-water tables.� The degree of loss of wet meadows due to incision is controlled by site characteristics such as the direction of groundwater flow, stratigraphic complexity, and the interaction of stream and groundwater.� Because different types of wet meadow vegetation have different groundwater depth requirements, patterns of vegetation can be used effectively and efficiently to provide a preliminary assessment of the controls on meadow location and sensitivity to stream incision.� At larger, watershed scale, similar variables can be used to understand the distribution and hydrologic function of riparian and meadow ecosystems.� The presence of perennial streams and wide valleys with significant sediment accumulations generally correlate with basins with meadows and wide riparian zones.� Alternatively, basins with low permeability bedrock and little sediment accumulation tend to lack meadows and have streams that can produce high-magnitude floods.� The ability to characterize the hydrologic setting and controls on meadow ecosystems are fundamental to our ability to develop a framework to support effective watershed management.