NMFS Biological Opinion
A Biological Opinion (BO) was issued by the National Marine Fisheries Service (NMFS) in September of 2000 for the U.S. Bureau of Reclamation's (Reclamation) operation and maintenance of Bradbury Dam (the Cachuma Project) on the Santa Ynez River in Santa Barbara County, California. NMFS is the agency that oversees protection of Southern California steelhead (Oncorhynchus mykiss). The BO addresses the effects of the proposed Cachuma Project operations on steelhead and its designated critical habitat in accordance with Section 7 of the Endangered Species Act of 1973.
The BO covers the proposed changes to Cachuma Project operations to improve habitat conditions downstream of Bradbury Dam for the steelhead, while maintaining current water deliveries. NMFS concluded that the new Cachuma Project operations are not likely to jeopardize the continued existence of the Southern California steelhead, and if carried forward many years into the future, is likely to appreciably increase the likelihood of survival and recovery of the species. The Cachuma Project provides water to over 210,000 people in Santa Barbara County and over 38,000 acres of cropland along the South Coast and in the Santa Ynez Valley.
Reclamation and the Cachuma Project Water Agencies have developed the proposed revisions to the Project operations since 1993. In that year, the Santa Ynez River Technical Advisory Committee (SYRTAC) was created to conduct studies of fish and aquatic habitat. The SYRTAC was ultimately tasked with the development of a Fish Management Plan for the lower Santa Ynez River. A concensus-based process was employed to develop the suite of proposed changes to project operations that are covered in the Biological Opinion.
The new operations in the BO focused on two major areas: (1) flow-related enhancement, and (2) tributary enhancement measures. Flow-related enhancement includes releases to maintain habitat for steelhead and releases to provide additional opportunities for steelhead to migrate into the system to spawn. Water for these releases is provided from "surcharging" Lake Cachuma in spill years and the year following a spill, or from Project yield in years when the reservoir does not spill. Additional actions are included for several tributaries downstream of Bradbury Dam. These actions include improving fish passage at existing impediments, purchasing conservation easements to protect good habitat, and planting trees along streambanks, among others.
Many of the proposed operations are being implemented based on an adaptive management strategy. This strategy allows managers to take advantage of new opportunities, evaluate current actions, and make changes as necessary to benefit steelhead. A long-term monitoring program is also required.
A complete description of proposed actions and the effects of the actions is outlined in the Biological Opinion.