We discuss a recent paper which evaluated the hydrologic changes resulting from a pond-and-plug meadow restoration project in the Sierra Nevada Mountains of California. In the study, measurements of streamflow into and out of the meadow suggested late-summer baseflow increased as much as five-fold when compared with prerestoration conditions. However, the volume of streamflow attributed to the restored meadow (49,000-96,000 m 3 over four months) would require that 2.5-4.8 m of saturated meadow soils drain during summer months. The groundwater data from this meadow record only 0.45 m of change over this timeframe, which is less than might be expected from plant use alone (0.75 m), suggesting this restored meadow may be acting as a water sink throughout summer rather than a source.
An investigation of the presence of enteric disease producing bacteria in a high quality mountain stream in Colorado yielded 11 isolants of members of the genus Salmonella and 51 isolants of organisms belonging to the Arizona group. An improved method for the recovery of these organisms from high quality water was developed and used successfully in the study. The presence of these potentially pathogenic bacteria, which appeared to be the result of contamination by wild or domestic animals, may be a potential hazard to public health.
In the Discussion, Nash et al. (2019) estimate the seasonal change in groundwater volume for a portion of the restored Sierra Nevada Meadow that we evaluated (Hunt et al. 2018) and use this estimate as an upper bound on the possible contribution to flow that is attributable to restoration. The authors conclude that raising the channel bed elevation and reconnecting the meadow floodplain most likely reduced summer streamflow. In contrast, we report at least a fivefold increase in baseflow from the meadow in the years following restoration. In addition, we observed that, after restoration, the previously intermittent stream below the meadow flowed continuously throughout the summer months, despite record drought conditions, and in 2015, the lowest snowpack on record. We suggest that the groundwater budget presented in the Discussion may not adequately represent conditions within the meadow because the authors extrapolate from 5 near‐channel groundwater wells across 62 ha of meadow and assume an area of influence that is approximately one‐sixth of the meadow area. We conclude that the conversion of an intermittent stream to perennial flow during drought conditions is a stronger check on our gauge data than the groundwater budget presented in the Discussion.
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