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The Susitna-Watana Dam: Image


Overview of the Susitna-Watana Dam:

In 2011, the State of Alaska resurrected previously discarded plans to dam the Susitna River—the first dam of its type or size to be proposed in the United States in more than 40 years. Here’s what you need to know:

The Susitna Dam, if built, would become the 5th tallest dam by volume in the United States and would pose significant harmful impacts to the Susitna River’s five species of salmon, caribou migration routes, and tourism- and fish-based businesses. The massive structure would be almost as tall as the Hoover Dam and three times taller than any other dam in Alaska. In an era when dams across the country are being removed, building a new dam of this size and scale is questionable both from an economic and ecological standpoint.

The Susitna River, where the dam is proposed, is America’s 15th largest river by volume and drains an area nearly the size of West Virginia. The vast valleys that feed the Susitna River comprise some of the state's most visited areas. It is the heart of Southcentral Alaska: massive mountains, deep forests, open tundra, and small communities with river-based economies. The river flows from mountain glaciers, unimpeded for 300 miles, through some of Alaska’s most rugged and wild landscapes to meet the Pacific Ocean near Anchorage where it is a significant contributor to Cook Inlet’s wild salmon fisheries.

What Kind of Dam are We Talking About and Where is it Being Proposed?

Size: The massive structure would be 705 feet tall, almost as high as the Hoover Dam and three times taller than any other dam in Alaska.

Type: This dam would span the width of the river, blocking upstream passage entirely. It would be “load-following,” meaning water is released to meet energy demands, which would create seasonal flows opposite of how the river normally flows.

Location: 87 river miles north of Talkeetna in the heart of one of the most visited, fished, and hunted areas of the state - one rich with salmon, moose, caribou, and bears.


Large-scale Dams Cause Significant Harmful Impacts and are Being Taken Down

Dams have been built throughout history to store water in reservoirs, control flooding and generate power. In the early 1900’s, the U.S. produced massive dam projects such as the Hoover Dam initially to control floods and produce power for a growing population, but also carried a symbolism of American power and progress during the Great Depression. Since then, at least 2119 dams have been removed in the U.S. due to them causing detrimental environmental impacts and threatening public safety. In just 2023, there were 80 dam removal projects, including the Klamath River dams, the largest one ever attempted in the U.S. "The dam removals reconnected more than 1,160 miles of rivers, improving river habitats for fish and wildlife. " (

Is Energy Fueled by Dams Considered “Sustainable”and “Renewable”?

Dams are often considered to produce "clean" and “renewable” energy. However, all energy infrastructure projects come with some negative impacts whether to our land, water or communities. Determining which projects come with minimal impact is crucial to responsible decision-making. Large-scale dams, however, entail substantial adverse effects and risks that outweigh their benefits.


Large-scale dams disrupt fish migration and wildlife habitat. The dam barrier blocks freshwater species from traditional spawning and rearing locations, and the river flow alterations create life-threatening conditions for them. This causes an alarming loss of freshwater biodiversity which negatively impacts riparian ecosystems, wildlife and local communities. 

Dams emit methane - a harmful greenhouse gas 25 times more potent than carbon dioxide. This greatly offsets the potential carbon emissions that some claim large dams will reduce. The EPA now includes reservoirs in their greenhouse gas reports.

The Dam is Not a Smart Investment for Alaskans

The estimated price tag to construct the dam is $5.6 billion ($7.2 billion in 2024 value), according to the Alaska Energy Authority (AEA).  

However, according to a cost analysis study by Erickson & Associates, AEA drastically underestimates the costs of the Susitna Dam by excluding $880 million ($1.2 billion 2024 value) in new transmission lines and facilities needed to move the power from the dam to the existing grid.


In addition, the costs to lease or purchase Native Corporation lands that the dam, the reservoir and the transmission lines would exist on have not been calculated or negotiated. State funds would also be required to mitigate damages to Susitna salmon fisheries. Hydropower mitigation costs billions of dollars on the Columbia River where they are desperately trying to save their endangered salmon runs.

This is expensive power when compared to other large hydro projects. In adjusted dollars, Montana’s 600-megawatt Libby Dam cost only $1 billion and Grand Coulee Dam in Washington State cost the same as the proposed Susitna dam but produces 10 times more electricity.

How Would the Dam Impact Fish, Wildlife, and Local Economies?

Load-following dam operations—like that proposed for the Susitna dam—severely alter the natural flow of river systems by dramatically reducing summer flows and increasing winter flows.

Altered river flows degrade or destroy sensitive salmon spawning and rearing habitat and important migration pathways which can severely impact the wild salmon populations the Susitna currently supports.

The proposed Susitna dam would create a 42-mile long reservoir that would flood 40,000 acres of prime bear, caribou and moose habitat—impacting one of Alaska’s most valued hunting regions.

Manipulated river flows and impacts to fish and wildlife resources threaten tourism and recreation businesses that are the cornerstone of the local economy, bringing in more than $200 million annually, and supporting more than 5,400 Alaskan jobs.

The Proposed Susitna Dam in NOT the Only Energy Option for Powering the Railbelt Region of Alaska

In 2021, Governor Dunleavy introduced the Renewable Portfolio Standard (RPS; SB179 and HB301) to reach 80% renewable electric generation on the Railbelt (the road system electric grid from Homer to Fairbanks) by 2040. In 2024, another version of this bill /Electrical Energy & Energy Portfolio Standards (HB368) was introduced by State Representative Rauscher. The utilities would receive incentives instead of fees to reach 60% by 2051, and clean energy includes coal along with standard renewable energy sources.

Investment in Alaska’s untapped renewable energy potential such as small-scale hydro, wind, solar, geothermal and tidal power can provide stable energy throughout Alaska for future generations without the building of any massive hydro projects. According to a recent National Renewable Energy Lab (NREL) cost analysis released in March 2024, 76% of renewable energy generation on the Railbelt can be achieved by 2040 through primarily wind and solar projects. This approach would result in savings of approximately $1.8 billion compared to a scenario with no new renewables added. The findings indicate that choosing the most cost-effective strategy for diversifying the state's energy sources eliminates the necessity for a harmful hydroelectric project like the Su Dam.

Although Alaska's dark winters create a challenge for solar energy, solar generation during the summer and the shoulder months can actually exceed the solar photovoltaic (PV)-system-rated outputs. Long, bright days, clear skies and reflective snow all contribute to high amounts of solar generation. Since the shelving of the Su Dam project in 2014, solar panel technology has significantly increased, and costs for solar installations have declined by 70% since 2010. In Anchorage, the Solarize program has helped put solar panels on 317 houses in Anchorage and 154 houses in Fairbanks. The Alaska-based solar company Renewable IPP developed the largest solar farm in the state in 2023 - an 8.5 megawatt (MW) solar farm in Houston, Alaska.

Alaska has huge potential for large-scale wind power with abundant natural wind resources available. Like solar, wind technology has greatly advanced, and wind power is now the cheapest electric energy on the earth. Our utility co-ops and independent power producers (IPPs) currently generate the Fire Island wind project (24.6 MW) in Anchorage and Eva Creek wind project (1.9 MW) near Healy. 


With both the Bipartisan Infrastructure Law (BIL) and the Inflation Reduction Act (IRA) funding bill passing, there has been a lot of money coming in to Alaska since 2022 and will continue. The IRA prioritizes incentive payments and tax credits to encourage clean energy, energy efficiency and carbon reduction. The IRA represents the single largest investment in clean energy in U.S. history. There is  $8.8 billion in rebates for home energy efficiency and electrification programs, and $74.5 million of that is for Alaskans. These rebate programs will provide Alaskans lower their energy use and costs.

2024 Update:

The proposed Susitna-Watana dam remains a threat to the wild and free-flowing Susitna River Watershed. The project was temporarily shelved in 2014 but gained attention again in 2020.


In spring of 2020, Alaska's Governor, Mike Dunleavy resurrected the project. Multiple presentations have been given to the State Legislature and State Agencies since then. The Governor and Alaska’s development agencies continue to pursue private investment opportunities from foreign companies and federal funding to move this boondoggle forward.

On January 26th, 2023, the Alaska Energy Authority, AEA, the state’s energy office, presented the Su Dam project to the Alaska House Energy Committee. The data provided in the presentation, including the cost-benefit and economic analyses, is almost a decade old, relying on information from 2014. The estimated amount of time to complete the project is 10-15 years, and the required transmission upgrades would undoubtedly prolong this timeline. 

The Alaska Energy Security Task Force, a 15-member committee selected by Governor Dunleavy, voted on and included moving forward with feasibility studies for the Su Dam in their extensive 102-page report of 60 steps and actions to be immediately implemented by state legislators on November 20th 2023 . The SRC commented against this recommendation during one of their two virtual public commentary periods. Diversifying our local energy generation to conserve the diminishing Cook Inlet natural gas supply is a necessity at this point. However, we believe the proposed the Su Dam clearly is not a "renewable" project, and that "diversification" does not mean relying on one massive hydro project to supply most of the Railbelt's energy demand.


As the state sets carbon reduction goals, taking responsible action to create economically responsible and clean energy systems for Alaskans means deciphering what projects will create the least harmful impacts on our livelihoods for decades to come. The Susitna-Watana Hydro project is certain to cause detrimental impacts to Southcentral Alaska’s economy and ecology.


With an estimated price tag of more than $7.2 billion dollars and devastating environmental impacts, the proposed dam remains an expensive, risky and extraordinarily damaging project. The board and members of the Susitna River Coalition remain as watchdogs, keeping track of any momentum towards the dam project and ready to take action.

The Susitna-Watana Dam: Programs
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