Since its inception, NHI has represented environmental interests in multiple forums to protect and restore the living elements of the San Francisco Bay Delta water system. The delta formed by the confluence of the two great river systems of California’s Central Valley – the Sacramento and the San Joaquin – is one of the defining environmental assets of the San Francisco Bay Area and of the nation. Through this labyrinth of diked channels pass all of the salmon runs that spawn in the headwaters as well as a considerable assemblage of native fishes and invertebrates.
The delta is also the hub of the world’s largest water delivery system. Water from the eleven regulated tributaries of the Central Valley flows into the delta and back out through the world's largest water export pumps, capable of diverting 15,000 cubic feet per second, which is equivalent to the flow of a large river. These pumps are connected via canals to 16 million urban water users in Southern California and to a $14 billion per-year irrigated agriculture industry in the Central Valley, the most productive farmland in the world.
However, these massive alterations have scrambled the hydrodynamics in the delta. The system has also been tragically compromised over the past century and a half by progressive land transformations. Altogether, over ninety-five percent of its tidal wetlands have been diked, filled, and converted into farmland.
NHI has worked on many fronts to sustain the delta as a living system, including:
- Acted as a leading environmental advocate through eight years of administrative trials leading to the current water quality control plan that limits water exports from the delta to protect its fish and wildlife;
- Successfully petitioned for listing of endangered fish species under the Endangered Species Act;
- Negotiated the “delta accords” that produced the CalFed Bay Delta Program;
- Staffed and infused the CalFed program with some of its core concepts including the Environmental Water Account, conjunctive management of surface and groundwater, and restoration as a way to reduce seismic risk, through the promulgation of the Environmentally Optimal Alternative: A Response to the CalFed Bay Delta Program;
- Negotiated the Vernalis Adaptive Management Program, a water quality compliance alternative for that part of the system, with the San Joaquin water districts, the U.S, Bureau of Reclamation, and other federal and state agencies; and
- Negotiated a Habitat Conservation Plan and Natural Communities Conservation Plan for the Bay Delta with water exporters and the fish and wildlife agencies.
