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Global Warming Will Challenge Balance Between Salmon, Hydropower
Climate change was the topic at a recent seminar sponsored by the University of Washington (UW )'s School of Communications . A hot topic throughout the weekend was researchers' discoveries about the effects global warming is likely to have on Northwest rivers. Rapid changes already underway in Earth's climate threaten to strike the Northwest right where it hurts Ñ our surface water supply.
In a nutshell, the Columbia and Snake Rivers are going to run a lot fuller in spring when the water is needed less and much lower when agriculture, utilities, and fish need it most. Electric utilities could find themselves starved for hydropower during summer months, leading to deadly consequences for migrating salmon if dam managers bottle up the rivers.
Edward Miles , a UW professor who has authored studies on climate change and marine policy, says government officials charged with protecting salmon populations have yet to respond to the looming water crunch. "I don't think the National Marine Fisheries Service recovery strategy deals with the whole risk salmon face. It deals with habitat restoration, but doesn't include [the effects of] climate change," says Miles.
Under scenarios predicted by researchers, snowfalls on the western front of the Cascades will fall by as much as 25% by the year 2020. Other mountain ranges would experience similar effects. That means a much lighter snow pack which warming temperatures will melt earlier in the spring. Torrents will come rushing down rivers in April, when dams' power demands are light, but the water could be gone by late summer. If the Bonneville Power Administration follows its traditional practice of reducing flow and spill when the water runs tight, Miles says, salmon could be left high and dry during critical migration periods. The problem is expected to intensify through the year 2040, when snowfalls could fall to half their current accumulation.
Meanwhile, river temperatures could rise by an average of two degrees, which Miles says would have a drastic impact on fish habitat. Miles says the Army Corp of Engineers , which operates the Columbia and Snake River dams, will need to alter flood control strategies significantly to manage hydropower resources and protect salmon runs. But he sees little indication the Corps has even begun to prepare for the effects of global warming. Congress has to approve such broad policy changes, Miles notes.
Miles' presentation posed the major question seminar participants had to struggle with: How can the looming water crisis be mitigated? Reservoir capacity is in short supply, especially along the narrow Snake River, making it impossible to store sufficient water in the spring to compensate for lower flows during the droughts.
Ironically, development of gas-fired generators, which will only exacerbate global warming, is one solution that seems destined to serve as a short-term fix. But John Harrison , spokesman for the Northwest Power Planning Council , pointed out that reducing energy use through conservation is, on a dollar-per-megawatt basis, cheaper than the infrastructure investments fossil-fuel power plant development will demand.
The most important challenge, Harrison and others agreed, was reducing the peak demand periods that last only 5% of the time but comprise more than a third of total energy use. Again, conservation would play a key role. Harrison said cities in the Northwest are pushing incentives to promote more efficient building designs and other efficiency measures. Renewable energy advocates meanwhile, point to wind power, now competitive with gas-fired generation, as another way to reduce pressure on power-producing dams without fueling the global warming threat.
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Kevin Fullerton