JUNEAU — A proposed massive dam in south-central Alaska could provide stable electricity rates in Alaska’s most populous region for a century, officials behind the effort said Tuesday.
The Alaska Energy Authority provided a special Senate committee with an update on the Susitna-Watana hydro project, including project cost estimates and timelines. The 735-foot dam would be located between Anchorage and Fairbanks and stand as one of the largest dams built in the U.S. in decades. The agency said the project would meet about half the energy demand of the Alaska Railbelt.
The current best estimate for capital costs is $5.2 billion, though a range of $3.7 billion to $6.5 billion was given. That figure is expected to be further refined as the project progresses. Annual operation and maintenance costs would start at an estimated $16 million, said Nick Szymoniak, a project economist. The economic assumptions included a 5 percent interest rate and debt repayment over 30 years. How the project would be funded has not yet been decided.
The power cost estimates assume no direct state funding, he said.
Critics fear the dam could hurt salmon and say it’s economically unjustifiable to pursue both the dam and a gas line, another potentially multibillion-dollar project to help meet the energy needs of Alaskans. The Coalition for Susitna Dam Alternatives also has said the risk of catastrophic failure cannot be dismissed, noting a 7.9 earthquake was recorded on the Denali Fault in 2002, 45 miles from the proposed dam site.
Plans for this year include implementation of a study plan. The authority is awaiting a decision from federal regulators on 14 studies, which is expected in April, project manager Wayne Dyok said.
The project timeline anticipates a decision on licensing in 2017 and seven years of construction, which would put project completion at 2024.