Water Quality Management

Bear reservoir on the Eldorado surrounded by trees and showing wooded hillsides. A streaming river flows down from a snow-capped mountain. Close-up view of water falling over rocks in a stream. View of Emerald Bay surrounded by snow on trees and moutains, near the Lake Tahoe Basin. Waterfall cascading down from the mountain top through a lush green forest.

The National Forests of the Pacific Southwest Region will play a crucial role in providing California's water in the years to come.

California, with its Mediterranean climate, large population, and extensive agriculture, depends heavily on management of its water resources. All major metropolitan areas rely on water imported from distant watersheds, primarily on National Forest System lands. The State's water system is currently under stress owing to increased demand, drought, restrictions on pumping, and limited funding available for infrastructure. In the future, the effects of climate change are likely to further stress California's water system.

Stewardship of water has been a key part of the Forest Service mission for over 100 years.

The Organic Act of 1897 that created the original forest reserves established two purposes for the reserves: a sustainable supply of timber, and "favorable conditions of water flow."

The Transfer Act of 1905 that created the Forest Service as an agency within the U.S. Department of Agriculture charged the new Service with ensuring that water from the forests would be available to downstream users.

Importance of National Forests in California Water Supply

National forests in California comprise about 20 percent of the area of the state, but owing to their location in mountainous headwaters, they provide almost half of the State's surface water. Annual national forest water yields range from 0.1 million acre-feet (maf) in the arid southern California forests to 5 maf in the rainy northwest. One acre-foot is roughly the amount of water needed to provide the annual domestic needs of two typical families.

Water Quality on National Forests

Several recent independent studies have shown that in general, waters on the National Forests of California are of high quality and provide beneficial uses. However, many activities on National Forest System lands have potential to affect water quality, and the Region is working with the state water-quality regulatory agency to improve its water quality management program. Many streams on National Forest System lands have been listed as impaired by the Environmental Protection Agency, and the Region and National Forests are working with the appropriate Regional Water Quality Control Boards to implement Total Maximum Daily Loads to control non-point source pollution.

California currently has only two designated Outstanding National Resource Waters: Lake Tahoe and Mono Lake. Both lakes are primarily within National Forest boundaries, and both are listed as impaired.