Key Issues

The Sierra Nevada Conservancy works though the Sierra Nevada Watershed Improvement Program (WIP), an initiative that takes a holistic approach to watershed and community resilience, to address some of the most pressing issues facing California.

Fire in the Sierra Nevada

Fire is a natural and essential process in the Sierra Nevada. Wildfires of the past burned mostly low to the ground and fairly slowly. They thinned out brush and smaller trees, leaving the larger trees to thrive with less competition for water and sunlight. The resulting forest structure of individual trees, clumps, and openings made it difficult for fires to burn intensely enough to kill the large healthy trees that dominated the landscape.

Today, many wildfires in the Sierra Nevada are burning larger and more severely. Decades of fire suppression and historic timber harvests have created overcrowded and unhealthy forests that fuel more destructive behavior. Fires like the King Fire, the Rim Fire, and the Butte Fire place California communities at risk and cause significant damage to the resources the Region provides, including water, wildlife habitat, recreational access, and carbon storage. Impacts from large, damaging wildfires in the Sierra are felt across the state as they degrade air quality, jeopardize the state water system, and offset progress towards California’s air quality and climate goals.

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The Sierra Nevada Region plays a critical role in California’s water system. More than 60 percent of California’s developed water supply originates in the Region. Snowpack in the Region is a critical form of water storage, and Sierra forests and meadows play important roles in ensuring water quality and reliability. Further, 75 percent of the fresh water that flows into the Sacramento-San Joaquin Delta comes from the Sierra. The Delta is the hub of the state of California’s water system, providing water to more than 25 million Californians and three million acres of agricultural land. Together, these two regions act as California’s natural water infrastructure, the foundation of a complex system that provides clean, reliable water for the state.

The quantity and quality of water from Sierra Nevada headwaters is threatened by overcrowded forests, degraded meadows, and a changing climate. Historically, Sierra forests and meadows yielded more water, of a higher quality, and later in the summer than they do today. Although changing weather patterns play an important role, less crowded forests consumed less water per acre and allowed a deeper snowpack to develop. Meadows characterized by meandering streams and floodplains acted like sponges, soaking up snowmelt, filtering it, and releasing it slowly—extending runoff into the dry California summer. Today, Sierra forests have grown more dense and many meadow floodplains are channelized. As a result, our Sierra headwaters are less capable of providing these beneficial services to the state water system.

Overcrowded forests also threaten our water supply infrastructure. They are less resilient to drought, beetle infestation, and wildfire. The result is unprecedented tree mortality in the Sierra Nevada—129 million killed by beetles and drought alone since 2010. Forests of dead trees create numerous challenges for water management, from an increase in flooding and landslides to a reduction in water quality and reservoir capacity.

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Greenhouse Gas Emissions Reduction

Mixed conifer forests of the Sierra Nevada play a significant role in regulating the climate. For thousands of years, they have absorbed carbon from the atmosphere and store enormous amounts both above and below ground. Today’s overcrowded forests absorb less carbon and are prone to damaging wildfires that threaten the security of existing carbon stocks. This past decade, large high-severity wildfires transformed our overcrowded forests, at least temporarily, from a net carbon sink to a major carbon source. The full extent of the impact to the climate is an active area of study and recent research indicates that unhealthy forests may pose a greater risk to California’s climate goals than once presumed. The carbon benefits of forest restoration treatments are well known and include a rapid post-treatment increase in sequestration rates, the amount stored, and the proportion held in large fire resilient trees.

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California is home to more diverse species and ecosystems than anywhere in the U.S. and the rich and varied landscapes of the Sierra Nevada Region host a majority of the state’s biodiversity. The Region covers only one quarter of the state’s land area but more than 60 percent of California’s vertebrate species, and 50 percent of its plant species call it home.

California’s State Wildlife Action Plan 2015 Update recognizes the “large array of habitats important for maintaining California’s wildlife diversity and abundance” and the important role the Sierra Nevada Conservancy could play in the “conservation and restoration of habitats for species at risk in the Sierra Nevada.” The California Department of Fish and Wildlife identifies 92 animals living in the Sierra Nevada and its foothills as Species of Greatest Conservation Need including the American Pika, Sierra Nevada Red Fox, and dozens more mammals, birds, reptiles, and amphibians. Across the range, over 200 species of plants found nowhere else in the world are listed as either rare or threatened.

Sierra Nevada biodiversity is at risk from large damaging wildfires. Although there are many threats to biodiversity in the Sierra Nevada, large high-severity wildfire is perhaps the most urgent. In one recent tragic example, the 2014 King Fire burned 97,717 acres in a matter of weeks, including nearly 50,000 acres at such high severity that it scorched the soil and killed nearly all plant life. Shortly thereafter, the Eldorado National Forest, which had been tracking Spotted Owl populations in the area for 23 years, reported the single largest population decline in the study’s history. To make matters worse, because the high-severity burn area was so large, it is unclear when (or if) much of this rich Sierra forest habitat will return.

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Community Resilience & Local Capacity

Rural communities in the Sierra Nevada face a unique set of challenges. Many struggle with economic diversification and job creation as opportunities associated with mining and timber production have declined. Tourism, recreation, and working landscapes remain the foundation of local economies. In this context, we have seen the devastation that a large, damaging wildfire can wreak on the citizens, communities, and natural resources of the Region. Economically, many Sierra Nevada communities are ill equipped to deal with the loss of business, infrastructure, and other major disruptions these events create.

To bring the Sierra Nevada Region to holistic health, local communities must be empowered to address urgent needs, plan for the future, and envision new tools and partnerships. Investments in emerging infrastructure and workforce development programs around sustainable forest management, including a distributed network of biomass energy production facilities co-located with wood products campuses, are particularly promising.

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Biomass Utilization

Restoring our forests to a more resilient, diverse, and fire-safe state requires that we remove significant amounts of biomass from the forest. Forest restoration efforts produce large quantities of downed small-diameter trees, brush and branches that must be removed from the forest for ecological purposes, public safety, and to reduce risk of damaging wildfire. Currently, the majority of the biomass produced by forest restoration projects, and nearly all slash created by commercial timber operations, is piled and burned in the forest. This biomass is a large and mostly untapped resource capable of producing alternative wood products that can offset the cost of restoration projects and fuel bioenergy plants that can produce heat, power, and biofuels, all while reducing greenhouse gas emissions compared to pile burning.

Recent innovations in biomass energy technology provide an opportunity for the environmentally sustainable use of excess forest biomass to create renewable baseload energy for California. Unfortunately, the lack of appropriate wood- and biomass-processing infrastructure remains a significant impediment to forest restoration efforts. Development of additional forest bioenergy power generation in the Sierra Nevada Region, co-located with innovative wood products campuses, would help increase the pace and scale of forest restoration activities while also creating jobs and opportunities for community economic development.

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Additional Information

More detailed information can be found in the following documents: