Hydropower generation within the Sierra Nevada, California involving more than 115 powerhouses, 421 jurisdictional dams, and 2,561 diversion dams (UCD Watershed Center FERC Database), creates the most significant bioregional impact on the health of Sierran aquatic ecosystems. The periodic relicensing of hydropower facilities regulated by the Federal Energy Regulatory Commission (FERC) is the only formal opportunity to reduce these impacts through new license conditions and settlement agreements that better reflect the range of modern societal goals. However, licensing efforts typically do not recognize the broader watershed and bioregional impacts of project operations, choosing instead to focus on river and stream reaches immediately adjacent to hydropower facilities. In addition, the FERC relicensing process tends to prescribe a narrow, inflexible range of operations for facilities, even in the face of considerable uncertainty about the future impacts of operations. This issue is particularly acute in the Sierra Nevada, where significant, well-documented changes in hydrologic conditions will impact hydropower operations and, in turn, aquatic ecosystems.
To date, stakeholders, agencies and utilities lack the necessary technical, legal and policy tools to support bioregional management that reduces the ecological impacts of hydropower operations, while adapting to uncertainty and change. We are developing an integrated program to address these issues in high elevation (above 1,000 ft.) dams of the west slope Sierra Nevada.
This report details the efforts of the UC Davis Center for Watershed Sciences (CWS) in the first year of a multi-year program to explore the development of new approaches to FERC licensing of hydropower facilities in the Sierra Nevada, California.
With support from the Resources Legacy Fund Foundation's Preserving Wild California initiative, the programme has focused on three broad issues:
- First, what are the legal and institutional barriers to changes to the FERC licensing process which could potentially improve the overall environmental performance of licensed facilities and allow them to adequately respond to scientific uncertainties and changes in conditions imposed by regional climate change?
- Second, how will climate change impact watershed hydrology and downstream aquatic and riparian ecosystem quality and where in the Sierran bioregion will these impacts be greatest?
- Finally, what operational tools can be used to manage FERC facilities in a truly adaptive context to mitigate the potential effects of climate change while minimising the impacts on hydropower generation?
