feature 4 fall 2006

Energizing Idaho

More than Idaho 130 dams and hydro projects give Idahoans some of the nation's cheapest electricity. But there are hidden costs.

Don Reading
Ben Johnson Associates

Idaho may be famous for its potatoes, but among outdoor recreationists it is even better known for its pristine rivers and world-class fishing, whitewater kayaking and rafting. There are 2,433 miles of floatable rivers in the Gem State, including the longest completely free-flowing river in the lower 48 states, the 425-mile Salmon River. The Salmon begins as not much more than a trickle at an elevation of about 8,000 feet in the Sawtooth and Whitecloud mountains of central Idaho and joins the Snake River shortly before it leaves the state. The Selway and Lochsa in northern Idaho are also free-flowing rivers famous for their recreational opportunities, while stretches such as the Henrys Fork of the Snake and Silver Creek are world-famous fly fishing destinations. But Idaho’s rivers do double duty. While they provide top-notch recreation that draws thousands of tourists each year, they also supply the state’s economy with inexpensive hydropower. Largely due to that energy source, Idaho currently has the lowest retail electricity rates in the nation—just half the national average of 9.48 cents per kilowatt hour (kWh).


	Brownlee Dam along the Snake River was completed in 1959. It was the first of a three-project Hells Canyon Complex that included the Hells Canyon and Oxbow dams.

All this cheap power comes from 136 hydroelectric plants with a total generating capacity of 2,468 megawatts. These plants produce 8.5 billion kWh of electricity annually, enough to supply half a million homes. At the state’s average retail rate of 5 cents per kWh, that power translates into a direct economic value of more than $400 million, not to mention the indirect “cost advantage” that cheap power offers in attracting and keeping businesses and jobs. In a world of uncertain and expensive energy, this asset helps stabilize Idaho’s economy.

Idaho’s hydropower facilities are located on 40 different waterways throughout the state. Their size ranges from Idaho Power’s Brownlee Dam at 675 megawatts to small, independently owned generators producing less than 1 kilowatt. Private utilities own two-thirds of the state’s hydroelectric production capacity and the federal government owns one-fifth. There are more than 80 small independent producers who contribute 11 percent of the hydropower capacity. These small hydro producers are located in 24 of the states 44 counties, with the majority of plants having a capacity of less than 1 megawatt. The remaining 2 percent is made up of municipal and coop utilities of which the City of Idaho Falls is the major contributor.

Harnessing Idaho’s rivers: a brief history

Early entrepreneurs in Idaho quickly saw the potential of the state’s huge snow pack unleashed each spring down thousands of creeks, streams and rivers, many of them with large drops in elevation. The first hydropower dam in Idaho was constructed in 1901 at Swan Falls on the Snake River, to provide power to the mines in Silver City. The project cost $250,000 and supplied electricity to the mines until they ceased operations in 1910. The plant was then upgraded, and eventually became a facility of Idaho Power Company.


	The Swan Falls Dam south of Boise was completed in 1901 to provide power to mines in Silver City. It eventually become the first major power source for Idaho Power Co.

The passage of the Reclamation Act in 1902 was crucial to hydropower development, since it freed up federal dollars for the construction of electric and irrigation facilities. The Act sparked the construction of numerous projects in the ensuing years, including the Minidoka Dam in 1908—the first federal facility in the Northwest—and Arrowrock Dam in 1915. When it was completed, Arrowrock was the tallest dam in the world, at just over 348 feet above the deepest point of the foundation, with a crest length of 1,100 feet.

In the 1930s a major controversy erupted over who should develop the rivers of the state for hydropower—private or public interests. The debate lasted for more than 20 years, focusing largely on Hells Canyon where Idaho Power wanted to build three relatively low dams while the U.S. Army Corps of Engineers proposed one or two high dams. Finally, state laws preventing the creation of public utility districts, together with the election of President Dwight Eisenhower, who favored private development, paved the way for Idaho Power to build its Hells Canyon Complex. This three-dam complex was completed in 1967 and still makes up nearly 70 percent of Idaho Power’s hydro generation capacity. The result of that lengthy battle was that private interests now control two-thirds of the hydropower production in the State of Idaho. By contrast, the neighboring states of Oregon and Washington derive most of their inexpensive hydropower from publicly owned dams.

Over the past two decades Idaho has grown rapidly, and the ability of hydropower to fill the state’s electricity needs has declined. In the past 15 years, with the building of gas-fired power plants, the percent of hydro production to total power production in Idaho has declined from 95 percent to 75 percent. In terms of electricity consumed by Idaho customers (whether produced in Idaho or not), hydropower now provides only 46 percent. Out-of-state coal plants provide about the same amount, with natural gas and renewables making up the rest.

What’s still out there: the future of hydropower in Idaho

According to a study by the Idaho National Laboratory (INL), there are 373 potential new hydropower sites in Idaho. Of those, 14 would be expansions of existing facilities, 86 currently have dams or diversions but no turbines, and the remaining 273 are undeveloped. The study estimates that these sites have a potential production capacity of 7,713 megawatts, more than three times the state’s current hydropower capacity of 2,391 megawatts. The sites are distributed throughout the state, and many would support only small power plants.

But hydropower does not come free. It produces electricity relatively cheaply and is often classified as “green” because it is fueled by a renewable resource (water) and doesn’t emit pollutants into the atmosphere. There are, however, some significant environmental costs associated with hydropower. Dams can raise water temperature, cause sedimentation, and damage riparian areas. They can also create large slack water pools that interfere with the ability of anadromous fish to migrate to and from the ocean.

In Idaho, the major impact is on salmon and steelhead. Before dams, the state’s free-flowing rivers supported large runs of both fish, and it was possible to catch 30-pound Chinook in downtown Boise. Today, several species of salmon are on the endangered list, and steelhead runs are declining.

Economically, the loss of those runs comes at a significant price, since recreational fishing can generate substantial economic activity. In 2001, for example, enough Chinook returned to allow the Idaho Department of Fish and Game to open a general salmon season in west central Idaho. Fish and Game issued 44,930 permits and conducted a survey of permittees that showed direct expenditures by anglers of $38.4 million, much of that in small river communities. Taking secondary economic impacts into account, the total economic activity in the state resulting from the 2001 salmon season was approximately $90 million.

Major hydro dams in the Columbia Basin. More than 40 large hydro projects on the Snake-Columbia system provide about a third of the region's electricity.

Salmon fishing can have a significant economic impact particularly in rural communities. A study conducted by the author for the Idaho Fish & Wildlife Foundation found that 23 percent of the spending in Riggins in 2001 was generated by the salmon season. The senior class at Riggins High School that year also looked at how the salmon season affected their town. They found that while local grocery stores usually stocked produce twice weekly, restocking took place every day during the salmon season, and sometimes twice a day. Similar impacts occurred in other kinds of businesses.

Obviously, restored salmon runs would have a significant positive impact on Idaho’s economy, and particularly on small river towns. Conversely, continued decimation of the runs will have a negative impact. While the return of salmon runs is more complicated than just the effect of hydropower production, its impact cannot be ignored.

Between recreation, irrigation, domestic water use, water storage and hydropower production, we are simply asking more from our rivers than they can give. Electric production, healthy fish populations and river recreation all contribute to the state’s economy, and their relative values must be carefully weighed as we consider whether—and how much—to increase hydropower production in Idaho.

Features: Out of Bounds • Irrigation Schemes • Boise Project • Energizing Idaho