[env-trinity] Redding.com Opinion: Curtis Knight & Doug Craig on Shasta Dam Raise

[Tom Stokely]

When Shasta Dam was finally completed, it was an engineering wonder — one that provided flood control to the Central Valley, power to its communities, and water to the Central Valley Project’s irrigators.
Unfortunately, the effects weren’t all positive.
The day the gates closed, as much as 75 percent of California’s prime salmon and steelhead spawning habitat disappeared. The winter-run chinook salmon — the only winter-run chinook in the world — lost access to the cold, spring-fed waters of the McCloud, where it evolved.
A hatchery was built to mitigate the salmon habitat losses, but new research tells us the hatchery may be hurting the salmon more than it’s helping them, degrading wild fish genetics and driving “boom and bust” population cycles common to monocultures.
Meanwhile, the flows in the Sacramento River below the dam were managed for water deliveries, not fish. Further downstream, the river was channelized, eliminating the floodplains — which we’re now learning are essential habitat for juvenile salmon.
In other words, Shasta Dam was good for part of the state, but a disaster for salmon, steelhead and other fish.
The dam, of course, is not coming down. In fact, it may even be raised. With anadromous fish populations a fraction of their historic, pre-dam numbers — and the salmon populations subject to wild oscillations — the problem isn’t one of nostalgia. It’s one of optimization.
In the presence of Shasta Dam, how do we protect and restore salmon and other wild fish stocks?
Restore Floodplains
Recent groundbreaking studies in the Knaggs Ranch area of the Yolo Bypass (conducted in part by CalTrout Central Region manager Jacob Katz) show us that a single-minded focus on riverine spawning habitat is misplaced.
Spawning habitat is wonderful, but it appears that floodplains — which once covered huge swaths of the Central Valley — are vital rearing habitat for juvenile salmon and steelhead. In recent trials performed in rice fields, salmon grew several times faster than the juvenile fish left in the Sacramento’s main channel.
In fact, researchers recorded growth rates of up to 1.5 mm per day — some of the fastest ever recorded in freshwater. When it comes to salmon smolt survival in the ocean, size is everything.
Happily, to leverage floodplain growth, we don’t need to revert the entire Central Valley to a marsh. Studies suggest that flooded rice fields provide excellent rearing habitat.
And many growers already flood their fields to rot rice stubble. And yes, opening up floodplains also offers flood protection to downstream communities.
In other words, more study is needed, but we’re working toward a solution that’s good for everyone — especially fish and farmers.
Mimic Natural Flows
Current flow regimes below Shasta Dam are based on archaic, outmoded models that harm both fish and do little to benefit downstream water users.
For example, Lake Shasta is drawn down every fall to make room for winter flooding, yet when winter precipitation doesn’t come, we’re suddenly short of water.
New models suggest it doesn’t have to be that way. In fact, a modification to Shasta Dam’s spillway would deliver a sizable increase in water holding capacity.
In addition, flows that better mimic natural flow cycles will benefit the Sacramento’s fisheries. For example, natural flows often ramped up quickly but fell slowly. Today, flows are often ramped down quite rapidly, resulting in stranding issues for juvenile fish, which live in the margins of the river.
Better flow management is needed.
Protect Wild Strongholds
While many of the Central Valley tributaries to the Sacramento River have been destroyed or dewatered, some remain strongholds for salmon and steelhead, including Mill Creek, Deer Creek and Butte Creek.
Since new tributaries aren’t being created, it’s imperative we protect those that remain.
That’s also why the restoration of Battle Creek is so important. Simply put, we’ll never get back what was lost above Shasta Dam, so it’s critical to protect what’s left below it.
A Promising Vision
Shasta Dam is clearly an engineering marvel. It’s our mission to see that it doesn’t become a larger environmental disaster.
Its impacts on California’s fisheries have already been sizable. But we believe proper management and a little vision — like the very promising restoration of wetlands and floodplain rearing habitat — mean future generations of Californians won’t view Shasta Dam as the engineering marvel that killed California’s once-abundant salmon and steelhead fisheries.
Curtis Knight is conservation director of CalTrout.http://www.redding.com/news/2013/sep/18/doug-craig-shasta-dam-ends-water-scarcity-8212/ 

Doug Craig: Shasta Dam ends water scarcity — but will bounty last?
I first laid eyes on Shasta Dam when it was “only” 46 years old and I was 28. Now almost three decades later, as we celebrate the 75th anniversary of its grand beginning, we would be remiss to not acknowledge its tremendous value to our state. Capable of holding more than 6 billion tons of water, Shasta Dam is the second largest in the nation. Can we fully grasp how much water this is?
Many of us take water for granted. Having clean, drinkable water instantly flow from our faucet whenever we want it isn’t something many Americans worry about. Taking long, hot showers or soaking in a hot tub when we feel like it, swimming in our own cool pool on a hot day, watering lawns, washing cars and irrigating our vegetable and flower gardens and fruit trees is just part of living that many have long enjoyed and expect to always have.
However, not everyone on Earth takes such luxuries for granted. According to the Organization for Economic Cooperation and Development’s Environmental Outlook to 2030 report, “Water scarcity will worsen due to unsustainable use and management of the resource as well as climate change” while “the number of people living in areas affected by severe water stress is expected to increase by another 1 billion to over 3.9 billion.” In other words, nearly half the human race will be living in areas of high water stress before today’s newborns graduate from high school.
Last year The Atlantic reported that in the next two decades, humanity’s “demand for fresh water will vastly outstrip reliable supply in many parts of the world” and “global warming is projected to exacerbate shortages in already water-stressed regions, even as it accelerates the rapid melting of glaciers and snow cover upon which a billion people depend for their ultimate source of water.”
This article sourced “the first U.S. Intelligence Community Assessment of Global Water Security” and predicted “that by 2030 humanity’s ‘annual global water requirements’ will exceed ‘current sustainable water supplies’ by forty percent.”
All but 3 percent of the world’s water supply is found in our salty (and undrinkable) oceans while most of the rest is in frozen ice sheets, glaciers, or high latitude permafrost.
About 1 percent of the world’s water is fresh and accessible, but thanks to global climate change, population growth, and careless over-consumption, each of us will have less of this precious resource in the future. Two years ago Scientific American described a study in Science that had determined that “Snowpack in the northern Rocky Mountains has shrunk at an unusually rapid pace during the past 30 years.”
The article stated the decline is “almost unprecedented” when compared with the past 800 years. Researchers “used tree rings to reconstruct a centuries-long record of snowpack throughout the entire Rocky Mountain range” and determined “that the plummeting snowpack could have serious consequences for more than 70 million people who depend on water from the runoff-fed Columbia, Colorado and Missouri rivers.” They include the residents of Southern California, who pull 25 percent of their water supply from the Colorado.
According to the Department of Ecology for the state of Washington, as the world continues to warm in the future, “more precipitation will fall as rain, not snow, and more snow will melt earlier in the spring.” This means less snowpack, less water when it is needed in the summer, shrinking glaciers, lower groundwater tables and less hydropower since dams cannot generate power without water.
Are more dams like Shasta the answer? If we are foolish enough to allow climate change to grow worse, does this idea warrant consideration? In the modern era, most of the western United States has depended on snowpack to provide drinking water and irrigation for life-sustaining agriculture. When our mountain areas can no longer hold millions of acre-feet of water in frozen reservoirs of ice because our planet is too warm, where will we turn for our fresh water, if not dams like Shasta?
Whether we build more dams or not, ignoring the problem of water scarcity is a luxury we can no longer afford. Our planet is undergoing massive, drastic change and the sooner we stop denying the fact, the sooner we can begin dealing with and preparing for it.
Doug Craig is a Redding psychologist. He blogs, mainly about climate change, atblogs.redding.com/dcraig.
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