Nearly a quarter of California’s fresh water supply flows through the Sacramento-San Joaquin Delta, an area comprised of tidal marshland and reclaimed land in the form of approx. 60 islands surrounded by 1700 km of levees. Maintaining the integrity of the Delta levee system is critical to protecting the state’s primary water supply and the overall economic and environmental health of the region. Land subsidence within the Delta poses a serious challenge to maintaining the delicate ecosystem and integrity of the water supply. Land subsidence behind the levees increases the stress from the water in the channels and can lead to levee failure or cause water seepage. The focus of this study is to determine the cumulative subsidence and subsidence rates and investigate subsidence along levees across the Sacramento-San Joaquin Delta.
We use data from NASA’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), collected at 40-day average interval from July 2009 through the current day. UAVSAR is an L-band SAR designed for differential interferometry (InSAR) and has sufficient resolution (~7 m product ground resolution) to resolve the levees from the surrounding area. The results of this project will be of value to both risk management associated with maintaining the levees in the area and to long-term plans for providing a more reliable water supply for California.
Research mentor: Dr. Cathleen E. Jones, NASA Jet Propulsion Laboratory
Community mentor: Joel Dudas, California Department of Water Resources