A broken levee near the San Joaquim-Sacramento River delta flooded nearly 12,000 acres of farmland in Central California on June 3, 2004. According to news reports, about 300 people were evacuated from the flood region.
An intricate series of levees and canals channel the fresh water from melting snow in the Sierra Nevada Mountains to the farmland in California’s Central Valley. A break on one levy can affect the distribution of water to others. In this case, up to one million acres of farmland may receive less water during June, the typical peak irrigation month. Additionally, the change in the water level could draw salty water from the San Francisco Bay into the freshwater delta, threatening to contaminate the drinking water of many of California’s cities.
The levee that broke is about 20 miles (32 kilometers) west of Stockton, and the breach allowed water from the Middle River to create a vast lake, visible in imagery taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on June 5. A false-color MODIS image taken on June 2 shows the water network before the levee broke. In both scenes, tan and bright green squares are agricultural fields.
The high-resolution images provided above are at MODIS’ maximum resolution. Both the June 5 and June 2 images are available in additional resolutions.
Dark brown squares mark fields that would ordinarily support irrigated crops in California’s Central Valley in this vegetation image. In 2009, a lack of water meant that the crops were not growing well or the fields lay fallow.
For more than 100 years, groups in the western United States have fought over water. During the 1880s, sheep ranchers and cattle ranchers argued over drinking water for their livestock on the high plains. In 1913, the city of Los Angeles began to draw water away from small agricultural communities in Owen Valley, leaving a dusty dry lake bed. In the late 1950s, construction of the Glen Canyon Dam catalyzed the American environmental movement. Today, farmers are fighting fishermen, environmentalists, and Native American tribes over the water in the Upper Klamath River Basin. The Landsat 7 satellite, launched by NASA and operated by the U.S. Geological Survey, documented an extreme drought in the area along the California/Oregon border in the spring of 2001.