Is Zinke trolling San Francisco with plan to dismantle city's reservoir?

US interior secretary's meeting with group in favor of Yosemite valley restoration met with puzzlement from experts

US interior secretary Ryan Zinke has prompted puzzlement by meeting with a group that seeks to dismantle a dam providing San Francisco's water, as experts wonder whether he is taking the fringe proposal seriously or trolling the city.

Zinke's Sunday discussion with Restore Hetch Hetchy concerned the dam at Hetch Hetchy reservoir in California's Yosemite national park. Removing it would restore the valley, which was once so beautiful that the environmentalist John Muir called it "one of nature's rarest and most precious mountain temples", to its natural state - and force San Francisco to figure out where else to store 90% of its water supply.