The San Francisco Bay Delta Estuary encompasses the deltas of the Sacramento and San Joaquin Rivers as well as the eastern margins of San Francisco Bay. Although the area has been extensively modified over the past 150 years, it remains biologically diverse while functioning as a central element in California’s water supply system. The Delta system is subject to several forces of change, including seismicity, land subsidence, sea level rise, and changes in flow magnitudes as well as such societal changes as increased urbanization, population growth, growing water demands, and changing agricultural practices. These changes threaten the integrity of the Delta and its capacity to function both as an important link in the state’s water supply system and as habitat for many species, some of which are threatened and endangered. In anticipation of the need to manage and respond to changes that have already and are likely to beset the Delta, a variety of planning activities have been undertaken. One such activity entails the development of a Bay Delta Conservation Plan (BDCP) by a consortium of federal, state, and local government agencies, environmental organizations, water supply entities, and other interested parties as a habitat conservation plan (see Appendix B). The BDCP covers 11 fish, 6 mammal, 12 bird, 2 reptile, 3 amphibian, 8 invertebrate, and 21 plant species (see Appendix C).
The present volume is the report of a panel appointed by the National Research Council at the request of the U.S. Secretaries of Interior and Commerce to review a working draft of the BDCP, dated November 18, 2010.3 Specifically, the panel was charged with providing a short report assessing the adequacy of the use of science and adaptive management in the draft BDCP (see Appendix A). The panel met on December 8 and 10, 2010 in San Francisco, California. On the first day the panel heard presentations from the various authors and sponsors of the draft BDCP and commentary from interested stakeholders. The panel spent the remainder of the meeting time as well as the intervening weeks examining, evaluating, and analyzing the draft BDCP. In the course of this review, the panel delved into supporting documents such as the Delta Risk Management Strategy and other relevant documents. This report refers to and comments on those documents in the context of the BDCP; however, this report is not a review of those documents.
The use of science has been emphasized in recent legislation, and science is
3 BDCP (Bay Delta Conservation Plan Steering Committee). 2010. Bay Delta Conservation Plan Working Draft. November 18. Available online at: http://www.resources.ca.gov/bdcp/. Last accessed April 26, 2011.
undoubtedly essential to the development of Delta plans generally. But science is only a starting point in the development of an integrated watershed-based plan, and it must be broadly applied. Moreover, science by itself cannot generate solutions to the myriad problems of the Delta that will satisfy the interests of all parties. Water scarcity in California is very real and science is not necessarily the sole solution to California’s water problems. There is simply not enough water to serve all desired uses. The situation surrounding the Delta is a symptom of scarcity. The effective management of scarcity requires not only the best science and technology, but also consideration of public and private values, usually through political processes, to arrive at plans of action which are scientifically sound but also incorporate and reflect the mix of differing societal values.
This review contains a background section describing the geography, hydrology, and history of the Delta and more detailed explications of the points noted above. Then the discussion is organized according to: (1) critical gaps in the scope of the draft BDCP, (2) the use of science in the draft BDCP (3) adaptive management in the BDCP, and, (4) the fragmentation of management that appears to characterize the effort.