In Sierra Club v. Tahoe Regional Planning Agency, the Ninth Circuit affirmed the district court’s summary judgment in favor of the Tahoe Regional Planning Agency (“TRPA”), finding that the TRPA’s final Environmental Impact Statement (“EIS”) for the agency’s Regional Plan Update (“RPU”) sufficiently addressed localized impacts on soil erosion and water quality. The 2012 RPU, among other things, restricted future development to areas that are already developed, and limited the extent of development in those areas. Plaintiffs, Sierra Club and Friends of the West Shore, challenged the RPU’s EIS, principally arguing that the RPU failed to adequately address the localized effects of the runoff created by the plan’s permitted development, and that the RPU improperly assumed that Best Management Practices (“BMPs”) would reduce water quality impacts of concentrated development.