Once considered marvels of engineering and the best way to provide power and water to towns and cities across America, dams are now considered harmful relics that damage river ecosystems and contribute to global warming. The documentary "DamNation" chronicles the dam removal movement and its success in bringing rivers back to life and the shift in values and priorities that have made that happen.

After a screening of the film held by UCLA's La Kretz Center for California Conservation Science at the Los Angeles Museum of Natural History, Matt Stoecker, the film's co-creator, co-producer and underwater photographer, described the first time he became aware of the destructiveness of dams, when as a youth he saw a steelhead trout jump five feet out of the water and hit its head on the concrete and bounce off. He explained that the documentary is the product of a discussion with friend and fellow environmentalist Yvon Chouinard, the founder of the clothing company Patagonia.

"There are so many negative environmental films, and we wanted to make a positive, inspirational story about what was happening. We wanted to show the destructive power of dams but also, when you remove a dam, how quickly watersheds and fisheries come back to life, how resilient nature is," said Stoecker, but there is a long way to go. Of the roughly 80,000 dams in the U.S., over half generate no power. "They're filled with sediment. They're just sitting there, harming watersheds."

But the film documents several success stories, including the Elwha Dam in Washington state. Of the thousand or so dams that have been demolished in the last couple of decades, "It's the biggest dam that's come down so far — 200 feet tall — 20 years after the push started," said Stoecker. "The beauty of all these dam removal projects is they were started by one or two people who wanted to see the river back, and it's that passion and motivation and persistence over a long period of time is what makes it happen."

Another two-decade saga involves the Matilija Dam on California's Ventura River, which hit snags over demolition plans that involved a cement channel that would not allow sediment to flow properly or allow complete passage of fish. "It's taken a lot longer than we thought, but by the end of 2015, we should have a new plan in place and hopefully start construction in the next two to three years," Stoecker projected.

"DamNation" also depicts the effects of fish hatcheries and the damage to the species when farmed fish mix with wild ones. "Hatcheries are the definition of unsustainable. It's like plugging into a life support system you can never unplug it from. You can never get back to self-sustainable populations of fish," said Stoecker, adding that building 'fish ladders' over dams or moving fish by barge or trucks is not the answer. "That is not restoration. Restoration is restoring ecosystem function."

He conceded that dams and hydroelectric power plants have had their benefits in the past, "but it's time to transition away from them. We have better means of getting energy, storing and using water, conserving and reclaiming water and flood protection now. There has been a cultural shift, and it's time to phase out some of this harmful technology."

He raised the additional issue of expense and wastefulness, calling dams "about the worst business model you can possibly think of, especially in the Southwest," where reservoirs lose over 20 percent of their water to evaporation. He cited studies from the University of Washington and elsewhere that showed dams "are some of the biggest emitters of methane, which is over 20 times more potent than carbon dioxide, trapping heat in the atmosphere. All the silt, sediment and organic material that falls into reservoirs gets stockpiled and the anaerobic activity produces methane."

The Glines Canyon Dam

The Glines Canyon Dam on Elwha River, with a crack and the message "Elwha Be Free" painted on the side by activists. (Photo: Mikal Jakubal)

Stoecker's message, reinforced in the film, was clear: "Dams are a climate change culprit. They're destroying ecosystems. They're terribly inefficient at storing water. But there are a lot of great alternatives," he said. "Texas has the most dams, but it's also making this great transition. Realizing that storing water out in the sun is a terrible idea, they've begun this program from Austin to San Antonio, working with the Nature Conservancy and the state, to use the land that is really porous to store water in underground aquifers. There's endless space, there's no evaporation, no sedimentation issues, so the water is cleaner. Groundwater recharge and storage is the future."

Although "DamNation" focuses on U.S. dams, Stoecker believes it has a cautionary and inspirational message that resonates globally, and is looking forward to upcoming screenings in Japan, Korea and tentatively Hong Kong and China. It will continue to play at film fests and hosted events in the U.S. and internationally (visit the film's website for info) and is available via iTunes, On Demand, and DVD/BluRay and at Patagonia.com.

"The response to it has been amazing. I had an 8-year-old kid come up to me after a screening recently and tell me, 'When I grow up I want to be a dam buster!'" said Stoecker, who is upbeat about the future. "I have a 1-year-old daughter, and I don't think she's ever going to own a gasoline-powered car. It’s all about transitions. We don't have to give anything up. Our lives are going to be improved, not diminished, by making this transition. I see it as a shift in values and a move away from what's harmful."

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