An advocacy group called the Center for Environmental Science, Accuracy and Reliability has filed a legal action in Federal Court against the National Park Service and the Department of Interior over the operations of Hetch-Hetchy Reservoir. The reservoir is located inside Yosemite National Park and is the main water supply for the city of San Francisco. The group contends that water stored and pumped from Hetch-Hetchy violates the Endangered Species Act and negatively impacts the Bay Delta ecosystem. The same group has taken legal action against federal agencies in the past to protest the listing and protection of endangered species. Hetch-Hetchy reservoir has been the focal point of controversy since its construction a hundred years ago, because the water stored there inundated a treasured scenic valley in Yosemite. Vic Bedoian reports from Fresno.