USGS Submissions

Flood protection in south Louisiana is largely dependent on earthen levees, and following Hurricane Katrina no infrastructure has received more scrutiny than the State's levee system. The USGS is working with local levee districts to map and monitor non-Federal levees using airborne and terrestrial lidar surveys.

Using USDA statistics and MODIS satellite data, USGS scientists have developed a consistent methodology to rapidly assess irrigation change across the conterminous United States.  MODIS Irrigated Agriculture Data for the U.S. maps were created for 2002 and 2007.  The 2002 and 2007 maps have estimated accuracy of 86 percent and 91 percent, respectively, based on assessments completed for central California, Snake River basin, and Central Plains. The overall change in irrigated area from 2002 to 2007 was +3 percent, but changes showed definite regional patterns.

Groundwater basins in California are used as local reservoirs to supplement water supplies. Water managers need information on the relationship between water extraction and land subsidence. Two studies are being conducted in the San Joaquin Valley to provide important information to manage and minimize the impacts of land subsidence to water-conveyance infrastructure, including the California Aqueduct.

Erosion of riverbanks along the Missouri River is a continuing concern of many of the Tribes within South Dakota. Changing reservoir levels combined with precipitation, wind, and ice result in conditions where substantial shoreline erosion may occur within a single season. The Lower Brule Sioux Tribe’s Environmental Protection Office, in cooperation with the USGS, is using ground-based Light Detection and Ranging (lidar) to obtain precise land-surface elevation data to accurately model the erosion. Initial lidar data were collected at two locations during February and March 2011.