Last week, an impressive septet from the UC Davis Center for Watershed Sciences published a thoughtful blog titled “What’s the dam problem with deadbeat dams?”.

The authors note that the environmental, political and social dynamics we have employed in building dams over the past 170 years have changed, sometimes radically. They recommend establishing a blue ribbon panel and analytics that would “transparently and objectively analyze natural resource management decisions in a careful and organized way”.

Restore Hetch Hetchy agrees. Like the UC Davis team, we are not anti-dam, and we also understand that “dams underpin much of California’s public safety and economy.”

But we also agree that it’s time to revisit the decisions to build some dams, whether for public safety, economic or environmental concerns. In our view, the O’Shaughnessy Dam cries out for reassessment due to the unmatched opportunity of returning Hetch Hetchy Valley in Yosemite National Park to its original splendor.

Some of our supporters have also expressed this sentiment – that we should not need to live with mistakes of the past – in similar terms, including:

It would tell the rest of the world we are not imprisoned by a decision we made 100 years ago. – Tom Philp, Pulitzer Prize winning journalist

We will need both intellectual humility and political courage to say, for example, that we made a mistake when we dammed Hetch Hetchy or Glen Canyon; let us take down with humility what we o­nce built with pride. —Terry Tempest Williams, American writer, educator, conservationist, and activist

To simply say, oh, the old dam is there, so forget it, is like saying, oh, the air already is polluted or pesticides already are in our food chain or that our nation’s infrastructure already is crumbling, so why try to do better? We can, and we should.” — Bob Binnewies, former Superintendent, Yosemite National Park

Emotionally, many of us would simply love to tear down the O’Shaughnessy Dam. But we understand it does provide water supply and hydropower benefits that must be redressed before restoration begins.

Its past time to undertake the analysis proposed by the UC Davis team at Hetch Hetchy, and to compare the short term costs of improving San Francisco’s water system with the extraordinary benefits that restoration would bring in the years, decades and centuries to come.