Throwing the switch at Bradley Lake.

• Author: Woodring, Jeannie
• Position: Commercial startup of the Bradley Lake hydroelectric project - Includes related article

This month marks the commercial startup of the Bradley Lake hydroelectric project, which carries the power of Kachemak Bay's pristine glaciers and abundant waters to 73 percent of the state's population. A 90-megawatt generating facility capable of producing 376 million kilowatt-hours annually, Bradley Lake is Alaska's largest hydroelectric project. At a cost of $312.5 million, it's also the biggest capital construction project ever undertaken by the state.

Capable of meeting 10 percent of the Railbelt's long-term energy requirements, the Bradley Lake project will "help us stabilize our power costs and reduce our dependence on fossil fuels," says Dave Eberle, project manage for the hydroelectric facility and an employee of the Alaska Energy Authority (AEA), the state agency responsible for Alaska's hydropower projects.

According to Eberle, statistics show that 95 percent of the electricity generated in the Railbelt area -- from the Kenai Peninsula to Fairbanks -- depends on fossil fuels. As fuel prices rise and fall, so do electrical rates -- creating a need for stable energy sources such as hydrogenerated electricity.

The fifth and largest of AEA's hydro projects, Bradley Lake's completion also marked several construction milestones: a $43 million savings over the original construction estimate, world records for tunnel boring and North America's first successful baldeagle-nest relocation project. Yet, to achieve these results, AEA and its contractors faced many challenges: operating in a delicate, rich natural environment; resolution of socioeconomic issues; designing a structure that could withstand earthquakes and cross fault zones; and coping with funding changes.

The challenges began nearly 30 years ago, when Bradley Lake was first recognized as a prime hydroelectric site. Sitting in a narrow glacial valley, 27 miles northeast from Homer at the tip of Kachemak Bay, the lake receives water from glaciers at the southern end of the Harding Icefield. In 1962 the site was authorized as a federal hydro project by the U.S. Army Corps of Engineers.

When the Crops failed to secure federal funding for construction, the Alaska Legislature assumed development of the project in 1982, giving responsibility to the Alaska Power Authority (now AEA).

The challenges had only begun. Before receiving a license from the Federal Energy Regulatory Commission to construct and operate the Bradley Lake hydroelectric facility, AEA had to answer many environmental questions. The Kachemak Bay area lies surrounded by state and federal parks and protected habitat regions. Not only would the proposed dam drown out the habitat of moose, goats and bears in the lake valley, but changes in the Bradley River flow could affect fish and waterfowl areas. Also discharge from the dam into Kachemak Bay had the potential to increase winter ice conditions.

With input from Homer residents, AEA worked through answers to the environmantal questions and by December 1985 received the FERC license for Bradley Lake. As AEA contracted with Stone & Webster Engineering Corp., of Boston, Mass., to design and engineer the project, Homer residents began asking other questions.

They sought to identify socioeconomic changes that could come with a potential construction boom. Residents wanted to know about the rules for local hire, the safety of workers on the job and the impact of job-seekers flocking to town.

AEA also faced engineering challenges. The proposed mountain valley dam, at 125 feet high and 600...