With climate change increasing drought conditions, big dam projects like New Melones no longer make sense.

The Big Dam Era Is Not Over

Last summer, construction began on what’s known as Site C, the third in a string of dams on the Peace River in northeast British Columbia. According to B.C. Hydro, the utility behind the projects, Site C will produce 35 percent of the energy with only 5 percent of the reservoir area of one of the existing dams. Once completed, the company says Site C “will be a source of clean, reliable and affordable electricity in B.C. for more than 100 years.”

Dams have long been touted as green, multiple-use projects. The reputation has roots in the “big dam era” of the early to mid 1900s, when engineering feats like Hoover and the Grand Coulee dazzled with their promises of clean power generation, flood control, and water storage. An information sheet for Site C lists job creation and benefits for First Nations people among the project’s dividends, but if we’ve learned anything from the past, it’s that there are plenty of reasons to be wary of these claims.

Opposition to Site C has been strong for years — which echoes a bitter battle over the New Melones Dam in California. Built in the 1970s in the Sierra Nevada foothills, the New Melones Dam was designed to replace and back water over an existing dam three quarters of a mile upstream. Despite protests, the impoundment covered a popular whitewater run on the Stanislaus River, where I and a generation of rafting guides had cut our boating teeth on rapids like Death Rock, Razorback Rapids, and Widow Maker.

Initial water inflow estimates for New Melones were based on data collected from 1922 to 1978. But when postconstruction conditions were later factored into the project’s models, it was clear that the earlier estimates were off, failing to predict drought and demand cycles “by a significant amount,” according to the U.S. Department of the Interior Bureau of Reclamation. New Melones has been near capacity only five times since it filled in 1978.

Congress initially authorized the dam in 1944, but construction didn’t begin until over 20 years later. In its final year of construction, the project was transferred to the Bureau of Reclamation, which had been optimistic, pre-selling irrigation contracts. Drought conditions from 1987 to 1992 forced the bureau to honor its commitments through expensive purchases of water from older dam projects. “It is believed that New Melones does not have a sustainable water supply sufficient to meet existing obligations for irrigation, wildlife enhancement, and water quality improvement,” notes the bureau on its Project History Page for New Melones.

Today, in a fifth year of “hot drought” — the hottest and driest spell in California since the late 1800s — New Melones is 25 percent full. Power generation has declined due to lack of inflow and outflow, just as it has at hydroelectric power plants statewide. According to the Pacific Institute, a global water research organization, California’s hydroelectricity production fell from an average of 18 percent of total electrical generation before the drought, to 12 percent in the three year period between 2011 and 2014. Energy production also became more costly by roughly $1.4 billion due to the shift from hydropower to natural gas.

Taking the history of New Melones into consideration, Site C, too, seems likely to underperform. The North American Drought Monitor has shown British Columbia to be abnormally dry for years. In some places, B.C. is undergoing severe longterm drought. Projections for the dam’s benefits haven’t yet been tempered by multiple scenarios in available climate models.

The downstream impacts of the Site C dam also remain under-assessed, but it seems certain they will be costly. In the years following the 1983 flooding in the Grand Canyon, researchers documented how channels downstream of dams widen or choke with sediment, native fishes decline or go extinct, and flow regimes alter drastically. Monetary values, previously underestimated or not accounted for at all, can be applied to these as well as upstream habitat impacts.

Research on the economic impacts of various environmental projects gives a rough estimate of $2,000 for the value each individual fish would have in increasing salmon populations. That’s money lost if populations decline. And the cost of losing spiritual and cultural benefits inherent in intact natural habitats? Priceless, according to First Nations people who reject the validity of applying a dollar amount to elements integral to their well-being.

For these and other reasons, resistance to Site C has been strong, with occupations, hunger strikes, and demonstrations at the river and near the homes and workplaces of decision makers. And it’s not just activists who are opposed — one expert called the project “fundamentally uneconomic,” standing to cost taxpayers and B.C. Hydro’s ratepayers $350 million annually due to outmoded technology and changing energy costs. More than 300 scholars (including me) have petitioned Prime Minister Justin Trudeau to revisit the plan, in a statement of concern pointing out “significant gaps and inadequacies” in regulatory review and environmental assessment. Review is warranted, given new options for storage and energy as well as Canada’s increasing aridity (despite its water-rich reputation).

Back in California, given New Melones and other disappointing dam projects, communities are thinking smaller and more cost effectively when meeting supply needs — particularly given climatic conditions that appear to be the new normal. New plans include decentralized systems to minimize energy-intensive transfer costs, indoor and outdoor conservation, and groundwater storage to avoid growing evaporation losses.

Large dam projects, in the current context, simply don’t make sense — a lesson we’ve learned the hard way.

“We have plenty of reservoirs that currently aren’t full,” says Juliet Christian-Smith, a climate scientist with the Union of Concerned Scientists, who suggested that if anything, preserving and storing groundwater aquifers is a much smarter and cost-effective strategy given the warming planet. “Any new storage — whether for groundwater or surface water,” Christian-Smith said, “must be designed to adapt to the fact that climate change is important to our water-management decisions.”

The Bureau of Reclamation suggests that the New Melones Dam “might become a case study of all that can go wrong with a project.” The bureau also says that the controversy surrounding New Melones was a signal that the large-dam era was over. And yet 1,200 miles due north, Site C is following diligently in its footsteps.

River guide Jeffe Aronson writes of returning to the Stanislaus River years after the New Melones reservoir was filled. The small towns near the river hadn’t fared well, with the promised economic boost drying up as soon as heavy equipment was hauled to the next job. When Jeffe stopped at the empty window of an abandoned market where he used to supply his trips, he felt a tap on his shoulder.

“An older gentleman, slightly familiar, smiled and offered his hand, asking, ‘Aren’t you one of those skirt-wearing raft hippies that used to come in and buy food back in the 1970s?’” Jeffe recalled. “I admitted that I was, and the man said, ‘My brother and I used to own this store. We went out of business soon after the dam went in. Whole damn town died. You were right. They lied to us, and I’ll regret it for the rest of my life.’”

Rebecca Lawton is a California-based author, fluvial geologist, and former Grand Canyon river guide. In 2015, she researched megadrought and the humanities as a Fulbright Visiting Research Chair at the University of Alberta.