Relicensing dams hangs on warm water, endangered fish
by Ken OlsenCooler water. And endangered fish.
These are two of the hurdles that stand between Idaho Power Co. and new federal licenses to operate the three dams on the Snake River known as the Hells Canyon complex. For more than four years, Idaho Power has been trying to obtain the water-pollution permits it needs for relicensing. Because the company’s dams are on the state boundary, it needs Clean Water Act permits from both Idaho and Oregon.
The company must submit an operating plan that demonstrates the dams won’t violate water-quality standards. The three key remaining issues are temperature, dissolved oxygen levels and total dissolved gas, with temperature usually being one of the most difficult to address.
Idaho Power must cool the water it discharges into the Snake to make it less harmful to fall chinook salmon. Currently, it’s as much as 6 degrees Fahrenheit too warm during the first few weeks of the October spawning season, says Paul DeVito, natural resource specialist for the Oregon Department of Environmental Quality.
The massive reservoirs created by Brownlee, Oxbow and Hells Canyon dams trap heat from the summer sun. But the water coming into the reservoir from upstream users – including agriculture – also helps create abnormally warm temperatures. And reduced flows, caused by irrigators, cities and towns and other water users, also contribute to the warm-water problem, making it difficult to figure out who’s responsible for what portion of the temperature increase.
As a result, Idaho Power may fund upstream watershed restoration in order to cool the water that ultimately flows into the Hells Canyon complex -- perhaps planting trees and shrubs to shade streams as well as increasing in-stream flows.
Beyond water-quality issues, Idaho Power must satisfy the federal government that it is doing enough to mitigate the damage its dams cause to bull trout, steelhead and salmon. It’s uncertain when the company will receive the necessary clearance from the U.S. Fish and Wildlife Service and NOAA Fisheries. And NOAA Fisheries has reserved its right to require fish passage at the dams in the future even if it signs off on the current license application.
Idaho Power submitted its application for license renewal with the Federal Energy Regulatory Commission in 2003. The company’s original 50-year operating license expired in 2005, and it has since been operating on an annual license. It now estimates it will receive its new license in 2010. The federal power commission has the option of issuing a license that is good for between 30 and 50 years. © High Country News