The Sierra Nevada region is plagued by drought, and because it’s California’s primary watershed, problems there ripple throughout the state. And the situation is getting worse as the climate warms.

Sediment landslide following high intensity fire.

Typically, mountain snowpack acts as a reservoir. It melts slowly through the summer and seeps into forests, where it’s filtered by a web of tree roots. But when temperatures rise and it rains instead of snows, there’s no reserve to sustain the forested watershed during dry summer months. Jim Branham is Executive Officer of the Sierra Nevada Conservancy.

Branham: “We’re seeing a lot of what otherwise would be healthy larger trees dying . . . even the vegetation that is still living goes through summer with a much lower moisture content than is normal.”

The weakened trees attract bark beetles, and provide fuel for intense fires that release massive amounts of global-warming carbon dioxide into the atmosphere.

But a broad-based coalition of state and federal government agencies, environmental groups, and companies hopes to turn things around. Called the Watershed Improvement Program, their plan to reforest and restore the watershed is designed to make it more resilient to drought, fire, and other climate change impacts.

Reporting credit: ChavoBart Digital Media.
Photo: High-intensity fires can be followed by severe erosion with large amounts of sediments destroying infrastructure, entering nearby waterways, impacting water quality and decreasing storage capacity in downstream reservoirs (source: The State of the Sierra Nevada’s Forests story map).

More Resources
The State of the Sierra Nevada’s Forests
Sierra Nevada Conservancy Watershed Improvement Program
New partnership seeks to restore Sierra forests
Critical Ecosystem In Danger, California’s Primary Water Supply at Risk

Diana Madson contributed regularly to Yale Climate Connections from 2014 to 2021. She enjoys exploring U.S.-based stories about unexpected and innovative solutions to climate change. In addition to her...