The image on the left shows the general location of the Twitchell Island insets. The two insets on the right show Twitchell Island, with the inset in the upper right corner showing a final seep detection product highlighting probable seepage areas along the levee. Image Credit: DEVELOP
Mentors/Advisers (affiliation): Cathleen Jones and Ben Holt (Jet Propulsion Laboratory/California Institute of Technology)
Team Location: Jet Propulsion Laboratory, Pasadena, California
Abstract: The Sacramento-San Joaquin Delta is home to California’s most threatened levee system. Around two-thirds of the state’s water supply and nearly all of the Central Valley’s agricultural water comes from the Delta. This levee system plays a vital role in keeping a large majority of California’s freshwater supply intact. For this study, we partnered with the California Department of Water Resources (CA-DWR), as they are tasked with the important role of maintaining a large portion of the Sacramento-San Joaquin Delta levee system. Differential interferometric synthetic aperture RADAR (DInSAR) products derived from NASA’s Uninhabited Aerial Vehicle – Synthetic Aperture RADAR (UAVSAR) were used to map areas of increased soil moisture content (levee seeps) along the Sacramento-San Joaquin Delta levee system. Previous DEVELOP JPL research performed in the spring and fall of 2012 have shown that methodologies using UAVSAR derived polarimetric data could accurately detect seep locations within different levee systems. This project extended work from the fall of 2012 to include DInSAR products derived from three years of data collected near monthly over the study area. Various processing techniques were applied to the DInSAR data to create a workflow that automatically pulls out the seep locations from within the study area. Currently, the CA-DWR does not have the means to locate these seeps without the use of vast in-situ surveys. Identifying the locations of these levee seeps helps the CA-DWR determine the overall health of the levees throughout the Delta in order to better make decisions on where to allocate resources for crucial levee repairs.