Why Is The Delta So Important?

The Sacramento-San Joaquin Delta is an important economic and environmental resource that benefits virtually all of California. The Delta provides agricultural and municipal water supplies for two-thirds of the state’s population and is a unique ecosystem that provides crucial habitat for important species. It is also an attractive destination for urban, environmental and recreational uses.

The Delta has experienced declines in ecosystem health over many years, but several years ago the decline became dramatic with a sharp drop in populations of delta smelt and several other fish species, and the rise of invasive species, including clams and predatory fish that change the ecosystem’s delicate food web.

The decline in fish population also coincided with the federal government mandating that California become more reliant on the Delta as the main source of water for Southern California and the Central Valley. In 2003, the federal Department of the Interior and its Bureau of Reclamation cut California’s exports from the Colorado River by half, ensuring sufficient water supplies were available for further downstream users like Las Vegas, Arizona and Mexico during drought conditions.

Both additional drought years and precipitous species decline created a crisis that put into question the ability of the state’s current water system to continue historic levels of water diversions to users in the south part of the state and fostered an urgency to define causes and create solutions to the Delta’s problems.