The Sierra Nevada and southern Cascade is a resource-rich region that supplies many benefits to its own communities and to urban residents downstream. It is the state's principal watershed, supplying up to two-thirds of California's developed water supply for urban areas. Its forests and agricultural lands store enough carbon to offset the annual CO2 emissions of 108 coal-fired power plants. It supplies up to half of California's annual timber yield and up to 15% of the state's power needs. Additionally, it is home to 60% of California's animal species and almost half of its plant species.

These critical ecosystem services are all at risk. In 2015, the Sierra's snowpack was at a 500 year low. Considering that the runoff from Sierra snowpack provides 60% of California's developed water supply, this significant decrease in water supply will have significant impacts on downstream users.

Frequent and severe wildfires have led to many communities experiencing hazardous air quality conditions and have imposed great costs upon Californians. The 2013 Rim Fire in Stanislaus National Forest and Yosemite National Park was the largest wildfire ever recorded in the Sierra, and the third largest in state history, burning over a quarter of a million acres. The 2014 King Fire in El Dorado County burned over 90,000 acres of land, with firefighting costs topping $5 million per day.

The following are impacts that the region is anticipated to continue experiencing:

  • Prolonged "extreme" drought conditions
  • Increased intensity and frequency of wildfires
  • Reduced snowpack 
  • Warmer temperatures
  • Flooding