The battle over Hetch Hetchy Valley continues today between those who wish to retain the dam and reservoir, and those who wish to drain the reservoir and return Hetch Hetchy Valley to its former state.
Those in favor of dam removal have pointed out that many actions by San Francisco since 1913 have been in violation of the Raker Act, which explicitly stated that power and water from Hetch Hetchy could not be sold to private interests.
Hydroelectric power generated from the Hetch Hetchy project is largely sold to Bay Area customers through a private power company, Pacific Gas & Electric (PG&E).
San Francisco was able to accomplish this in 1925 by claiming it had run out of funds to extend the Hetch Hetchy transmission line all the way to the city.
The terminus of the incomplete line was "conveniently located next to a PG&E substation", which connected to PG&E's private line which in turn bridged the gap to San Francisco.
The city justified this as a temporary measure, but no attempt to follow through with completing the municipal grid was ever made.
Peter Byrne of SF Weekly has stated that "the plain language of the Raker Act itself and experts who are familiar with the act (and have no stake in city politics) all agree: The city of San Francisco is not in violation of the Raker Act."
Harold L. Ickes, Secretary of the Interior in the late 1930s, said there was a violation of the Raker Act, but he and the city reached an agreement in 1945.
In 2015, Restore Hetch Hetchy filed a complaint arguing that the construction of the dam had violated a provision in the constitution of California about water use, but the lawsuit was rejected by an appeals court and later the California State Supreme Court.

Preservation groups including the Sierra Club and Restore Hetch Hetchy state that draining Hetch Hetchy would open the valley back up to recreation, a right that should be provided to the American people because the reservoir is within the legal boundaries of a national park.
They acknowledge that a concerted effort would have to be made to control the introduction of wildlife and tourism back into the valley in order to prevent destabilization of the ecosystem, and that it might be decades or even centuries before the valley could be returned to natural conditions.

In 1987, the idea of razing the O'Shaughnessy Dam gained an adherent in Don Hodel, then Secretary of the Department of the Interior under President Ronald Reagan.
Hodel called for a study of the effect of tearing down the dam.
The National Park Service concluded that two years after draining the valley, grasses would cover most of its floor and within 10 years, clumps of cone-bearing trees and some oaks would take root.
Within 50 years, vegetative cover would be complete except for exposed rocky areas.
In this unmanaged scenario, where nature is left to take hold in the valley, eventually a forest would grow, rather than the meadow being restored.
However, the same NPS study also finds that with intensive management, an outcome in which "the entire valley would appear much as it did before construction of the reservoir" is feasible.

The dam would not have to be completely removed; rather, it would only be necessary to cut a hole through the base in order to drain the water and restore natural flows of the Tuolumne River.
Most of the dam would remain in place, both to avoid the enormous costs of demolition and removal, and to serve as a monument for the workers who built it.
The water storage provided at Hetch Hetchy could be transferred into Lake Don Pedro lower on the Tuolumne River by raising the New Don Pedro Dam 30 ft (9.1 m).
Water could be diverted into the Kirkwood and Moccasin Powerhouses using lower-impact diversion dams, providing power generation on a seasonal basis, and the enlarged height at Don Pedro would also increase power generation there.
Furthermore, the removal of O'Shaughnessy Dam would not require costly sediment control measures, as would be typical on most dam removal projects, because of the high quality of the Tuolumne River water – in the firs
The battle over Hetch Hetchy Valley continues today between those who wish to retain the dam and reservoir, and those who wish to drain the reservoir and return Hetch Hetchy Valley to its former state. Those in favor of dam removal have pointed out that many actions by San Francisco since 1913 have been in violation of the Raker Act, which explicitly stated that power and water from Hetch Hetchy could not be sold to private interests. Hydroelectric power generated from the Hetch Hetchy project is largely sold to Bay Area customers through a private power company, Pacific Gas & Electric (PG&E). San Francisco was able to accomplish this in 1925 by claiming it had run out of funds to extend the Hetch Hetchy transmission line all the way to the city. The terminus of the incomplete line was "conveniently located next to a PG&E substation", which connected to PG&E's private line which in turn bridged the gap to San Francisco. The city justified this as a temporary measure, but no attempt to follow through with completing the municipal grid was ever made. Peter Byrne of SF Weekly has stated that "the plain language of the Raker Act itself and experts who are familiar with the act (and have no stake in city politics) all agree: The city of San Francisco is not in violation of the Raker Act." Harold L. Ickes, Secretary of the Interior in the late 1930s, said there was a violation of the Raker Act, but he and the city reached an agreement in 1945. In 2015, Restore Hetch Hetchy filed a complaint arguing that the construction of the dam had violated a provision in the constitution of California about water use, but the lawsuit was rejected by an appeals court and later the California State Supreme Court.
Preservation groups including the Sierra Club and Restore Hetch Hetchy state that draining Hetch Hetchy would open the valley back up to recreation, a right that should be provided to the American people because the reservoir is within the legal boundaries of a national park. They acknowledge that a concerted effort would have to be made to control the introduction of wildlife and tourism back into the valley in order to prevent destabilization of the ecosystem, and that it might be decades or even centuries before the valley could be returned to natural conditions.
In 1987, the idea of razing the O'Shaughnessy Dam gained an adherent in Don Hodel, then Secretary of the Department of the Interior under President Ronald Reagan. Hodel called for a study of the effect of tearing down the dam. The National Park Service concluded that two years after draining the valley, grasses would cover most of its floor and within 10 years, clumps of cone-bearing trees and some oaks would take root. Within 50 years, vegetative cover would be complete except for exposed rocky areas. In this unmanaged scenario, where nature is left to take hold in the valley, eventually a forest would grow, rather than the meadow being restored. However, the same NPS study also finds that with intensive management, an outcome in which "the entire valley would appear much as it did before construction of the reservoir" is feasible.
The dam would not have to be completely removed; rather, it would only be necessary to cut a hole through the base in order to drain the water and restore natural flows of the Tuolumne River. Most of the dam would remain in place, both to avoid the enormous costs of demolition and removal, and to serve as a monument for the workers who built it. The water storage provided at Hetch Hetchy could be transferred into Lake Don Pedro lower on the Tuolumne River by raising the New Don Pedro Dam 30 ft (9.1 m). Water could be diverted into the Kirkwood and Moccasin Powerhouses using lower-impact diversion dams, providing power generation on a seasonal basis, and the enlarged height at Don Pedro would also increase power generation there. Furthermore, the removal of O'Shaughnessy Dam would not require costly sediment control measures, as would be typical on most dam removal projects, because of the high quality of the Tuolumne River water – in the firs
Hetch Hetchy