Coarse and Fine Sediment Management to Achieve the Restoration Goal for the San Joaquin River

Spring-run and fall-run Chinook salmon were extirpated from the San Joaquin River in the late 1940’s.  Achieving the Restoration Goal of re-establishing naturally producing, self-sustaining populations will require adequate quantity and quality of spawning habitat in the reach immediately downstream of Friant Dam. The San Joaquin River has higher sand storage and lower gradient than its similar-scaled tributaries downstream (Merced, Tuolumne, and Stanislaus rivers), and poor gravel quality may be one of many challenges in achieving the Restoration Goal. Initial gravel quality information has been collected,  temperature modeling and experimental flow releases are being conducted to evaluate temporal and spatial extent of suitable spawning and egg incubation, a sand storage evaluation is underway, and bedload transport rates have been collected during January 2011 flood control releases. This information will be considered with anticipated future Restoration Flow releases and flood control releases to develop fine sediment and coarse sediment (including spawning gravel) management strategies for the reach immediately downstream of Friant Dam. The overall objective of sediment management strategies is increasing fry and juvenile Chinook salmon production to help achieve the Restoration Goal. This presentation will summarize information collected to date, present analyses that inform potential sediment management strategies, and will discuss tradeoffs of potential sediment management strategies.