Measurements of streambed permeability from two restored reaches of the lower Merced River, California

Field measurements of saturated hydraulic conductivity were used to characterize the streambed permeability for two reaches of the lower Merced River in California's Central Valley to support research intended to evaluate the extent to which large-scale restoration projects provided improved salmon spawning habitat. A related goal of this study was to improve our understanding of the geomorphic factors influencing spawning site selection by salmon. Saturated hydraulic conductivity, denoted by K, was measured with a backpack permeameter and modified Mark VI groundwater standpipe using the constant head method of Terhune [1958]. For each reach, permeameter measurements were collected at ten sites spanning a single pool-riffle transition.