The latest cost estimate for building the proposed Susitna-Watana Hydroelectric Project is $4.3 billion, according to the civil engineer who has headed the project since November.
Wayne Dyok addressed the Anchorage Chamber of Commerce on Monday and laid out preliminary steps taken since the Alaska Legislature appropriated $66 million for the dam, access and license planning last year.
The Alaska Energy Authority filed a summary of available information on the project Dec. 29 with the Federal Energy Regulatory Commission, which kicked off the licensing process. The federal commission had 60 days to produce a scoping document and beat the Monday deadline by four days.
"They're taking this project very seriously," Dyok said.
The FERC scoping document, he said, identifies issues that must be evaluated for the environmental impact statement that the commission ultimately will produce.
The commission has planned scoping meetings for the end of next month in Anchorage, Fairbanks, Wasilla, Talkeetna and Cantwell.
"What we want is an open, honest and transparent process for moving forward," he said.
The federal government in the 1970s first studied the Susitna River for its hydroelectric potential. The Alaska Power Authority in 1983 submitted a license application.
The state spent $145 million on the project for field work, biological studies and other activities in the 1980s, but financing problems, the availability of electricity powered by natural gas turbines and the declining price of crude oil, Alaska's main income source, resulted in a decision to end the project.
A Susitna River dam has received renewed interest as power generation plants have aged and state officials seek to diversify power sources.
The proposed site is 184 miles upstream from the mouth of the Susitna River and upstream of Devil's Canyon, which means the only fish whose route would be interrupted by a dam would be the king salmon population that can negotiate the powerful hydraulics of that stretch of river.
Dyok said the Alaska Energy Authority is looking at a 700-foot dam, smaller than the 885-foot version once considered.
"It better meets the Railbelt needs, quite frankly," he said.
The project would generate 2.5 million megawatt hours annually, about half the current 5.4 million megawatt hours used annually in the Railbelt, including Anchorage, Fairbanks, the Mat-Su and the Kenai Peninsula. The Railbelt covers most of the state's population.
A road would precede dam construction.
Three sites have been identified. The cheapest financially, though not necessarily environmentally, would descend south from the Denali Highway, Dyok said.
Two others in the mix would begin from Alaska Railroad property just east of the Parks Highway and proceed east.
A construction camp would accommodate a peak of 1,000 workers, though the total would be closer to 800 more of the time, Dyok said. A small permanent camp would house hydroelectric project operators.
Dyok has been on the job for just four months but is not a new face on the project. A hydraulics engineer, he worked on the previous project in the 1980s and joked that he took a 25-year break.
The current project will build on past work. The state had 33 years of flow data in the 1980s and now has 25 more.
The more recent data showed peak snow melt runoff is now one to two weeks earlier, Dyok said.
Dyok stressed the project is in the preliminary stages. Much more will be known about the feasibility of the project in a year, he said.
The FERC licensing process will take until at least 2017, he said. Construction likely would take six years, meaning the earliest the hydroelectric project could come online is 2023.