San Francisco has a special deal granted to no other city in the United States: A dam and reservoir in the middle of a national park that belongs to all of the American people.

With that special deal, approved by Congress in the Raker Act of 1913, came significant restrictions on public use – no touching waters within one mile of the reservoir. No other national park has such a rule.

But Congress also imposed some responsibilities.

Rep. Dan Lungren, R-Gold River, believes that San Francisco is not living up to those responsibilities. In a Dec. 7 letter, he asked Interior Secretary Ken Salazar to investigate San Francisco's compliance with the Raker Act. Get it started, sooner rather than later.

The law, Lungren points out, requires that San Francisco "fully develop and use other available water resources before it begins to export water it captures from the Tuolumne River." The purpose is to ensure that water is not "unnecessarily exploited."

Water is a scarce resource and we should not be using pristine sources unnecessarily.

Specifically, Lungren believes that San Francisco could be doing much more to use recycled water – instead of using Tuolumne River water – for landscaping, toilet flushing, mixing concrete and more. Where Orange County uses 35 million gallons a day of recycled water and Los Angeles uses 28 MGD, San Francisco has no large-scale water recycling. Zero.

By 2035, San Francisco expects to use 4 MGD of recycled water, hardly ambitious. By comparison, Sacramento uses 5 MGD of recycled water today, but expects to expand to 40 MGD in the next 20 years.

Lungren also believes that a city that receives an average of 20 inches of rain each year (equivalent to 49 MGD), could be doing much more to harvest rainwater.

Finally, Lungren points out that San Francisco today "has virtually abandoned use of all groundwater supplies."

An investigation would pin down use of local water supplies. "If San Francisco can show that it is leading the state in recycling and recovery," Lungren told The Bee editorial board, "maybe it can be a model for the state."

But if San Francisco can rely less on Tuolumne River water, that provides an opportunity to restore the national park ideal. "There is only one Sierra," Lungren says. "And only one Yosemite." But part of Yosemite, Hetch Hetchy Valley, is submerged for the benefit of one city. That's got to change.

A start is for San Francisco not to rely unnecessarily on the Tuolumne River.

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