“To fit on the crowded river, the new reservoir would be squeezed so tightly between another reservoir downstream and a hydroelectric plant upstream that some of the hydroelectric powerhouses would be inundated. The Temperance Flat design alludes to mitigating the loss, but the new configuration would still reduce the state’s hydroelectric capacity.
Environmentalists and scientists contend that Temperance Flat would also obliterate habitat for native fish populations and hamper an ongoing project downstream to restore salmon. Local Indian tribes object to it because it would flood more than 150 Native American archaeological and historical sites. And it would destroy one of the last remaining free-flowing reaches of the river, where rafters and kayakers ride rapids.”
Spurned dam projects are called vampires because they so often rise from the dead. The term perfectly fits two hoary, misguided proposals under consideration in California as a result of passage of Proposition 1, the 2014 bond measure that set aside $2.7 billion for new water storage.
In May, the California Water Commission will begin to choose among 11 projects that have applied for the funding, including the undead dams.
The biggest boondoggle before the commission is Temperance Flat, the latest iteration of a six-decade-old project that would add a 10th dam to the all-but-emptied San Joaquin River. The state Water Resources Control Board has already deemed the San Joaquin “fully appropriated,” which means that in most years all its water is allocated, chiefly to farmers. As a result, except in extremely wet years, Temperance Flat’s large reservoir would capture very little water.
To fit on the crowded river, the new reservoir would be squeezed so tightly between another reservoir downstream and a hydroelectric plant upstream that some of the hydroelectric powerhouses would be inundated. The Temperance Flat design alludes to mitigating the loss, but the new configuration would still reduce the state’s hydroelectric capacity.
Environmentalists and scientists contend that Temperance Flat would also obliterate habitat for native fish populations and hamper an ongoing project downstream to restore salmon. Local Indian tribes object to it because it would flood more than 150 Native American archaeological and historical sites. And it would destroy one of the last remaining free-flowing reaches of the river, where rafters and kayakers ride rapids.
The fish, cultural artifacts and recreational opportunities all have significant worth, but the project’s benefit-cost analysis shamelessly assigns them no value in order to arrive at the conclusion that the dam would provide net environmental and recreational benefits — and even then the ratio is nearly a wash. Take the lost fish, artifacts and recreation into account, and the project doesn’t come close to penciling out.
The second vampire project, the Sites Reservoir in the Sacramento Valley, was first proposed more than half a century ago. It at least would have the advantage of being an offstream reservoir — two large dams and up to nine small ones would be built to hold diverted Sacramento River water within what is now a large, shallow valley. Because the reservoir isn’t on the river itself, where it could block fish and sediment migration, the project wouldn’t be as environmentally destructive as Temperance Flat, but it would further deplete the Sacramento, jeopardizing already critically endangered salmon.
The California Department of Fish and Wildlife recommended two years ago that Sites backers should agree to fill the reservoir only in very wet periods, when river flows surpass minimums set aside to protect salmon. But the proponents, about 30 regional and local water agencies, ignored the recommendation. In January, Fish and Wildlife concluded the project would reduce survival of salmon and other native fish.
That’s a crucial finding, because Proposition 1 requires that projects must show net environmental benefits (among other public goods) to be eligible for funding. Doug Obegi, a senior water attorney for the Natural Resources Defense Council, told me a smaller reservoir that would divert less water might meet that requirement, but what has been proposed instead “would be devastating for the state salmon fishery and the environment.”
It’s no coincidence that Temperance Flat and Sites are the two most expensive storage projects under consideration. Large dams come with steep price tags — so high, in fact, according to a 2014 Oxford University study of 245 dam projects, that even without considering dams’ usually extensive environmental and social damage, “the “construction costs of large dams are too high to yield a positive return.”
Nevertheless, California dam proponents want state taxpayers to pay about half of Temperance Flat’s projected $2.7-billion cost and a third of Sites’ whopping $5.2-billion outlay — each project would use up at least half of all the funds voters set aside for water storage in Proposition 1.
Contrast those numbers with the cost of San Diego’s proposal before the Water Commission, a $1.2-billion recycling project to clean, store in an offstream reservoir and eventually reuse wastewater now being dumped into the ocean. According to the city, its Pure Water program, which is already under way, will create a double benefit — reducing ocean pollution while increasing water supply. And taxpayers are being asked to foot just $219 million of the cost.
Big dam proponents, including many Central Valley farmers, often complain that California hasn’t enlarged its water storage capacity since 1978, when the New Melones Dam on the Stanislaus River was completed, but that’s a myth. A peer-reviewed study in a journal devoted to Sacramento-San Joaquin River scholarship found that storage capacity has increased more than 4.6 million acre feet, since 1980, surpassing the capacity of Lake Shasta, the state’s largest reservoir. The increase, however, has been achieved without building new dams. Instead, it has come about with smart projects like San Diego’s that are smaller, cheaper, decentralized, close to end-users, and environmentally beneficial.
Dams are an old-fashioned brute-force solution to problems that can be addressed now with far less expense and environmental disruption. The Water Commission ought to acknowledge that reality by putting a stake through the Temperance Flat Dam and Sites Reservoir.
Jacques Leslie is a contributing writer to Opinion.