Dams are used to generate hydroelectricity, prevent floods, irrigate farms and supply water to cities. However they also wreck ecosystems and can destroy the livelihood of families and communities, who lose their land to reservoirs or see the dams destroy their fisheries.
These growing environmental concerns put pressure on the abandonment of dam-building projects, which have rapidly diminished the number of wild rivers in the world. In fact many dams have been demolished in order to reinstate river habitats and revive fisheries. Back in 1995 the US dam-building era was declared over by Daniel Beard, head of the US Bureau of Reclamation, the nation's main constructor of dams.
Now however, after years in the “environmental doghouse”, large dams are being promoted as a source of low-carbon energy, and the 600-megawatt Susitna project looks like it could be the first to get the green light.
Planning for the Susitna Hydroelectric Project first began back in the 1960’s as a means to supply electricity to the railbelt region of Alaska (areas served by the Alaska Railroad), including the cities of Anchorage and Fairbanks, but it was shelved on environmental grounds and also due to the abundant supply of cheap oil. However, since 1986 the price of oil has increased by over 800%, and the cost of energy for Alaskans has skyrocketed, reviving interest in the proposal. In July state legislators unanimously voted to approve the scheme and on the 29th December the Alaska Energy Authority will submit a preliminary licence application to the Federal Energy Regulatory Commission. If approved, it would be the country's first hydroelectric mega-dam for 40 years, its fifth tallest (just 8 metres shy of the Hoover dam), and could trigger a national debate on dam construction.
Maybe the dam-building era isn’t as dead as Daniel Beard once thought.
In a recent press conference, Alaskan Governor Sean Parnell said that, the licensing to approve the project is expected to take six years, the construction will take a further five years and power should then be online by 2023.
At the moment Alaska is heavily dependant on expensive fuels such as diesel, but "the Susitna-Watana Hydro Project is part of a comprehensive energy package that will help Alaskans in a number of different ways," Parnell said. "It will grow jobs now and into the future, and it will help Alaska reach its goal of 50 percent renewable energy by 2025." Part of a legislation established in 2010.
The intended dam will be 700 feet high and will create a 39 mile long reservoir with a maximum width of two miles. The prediction is that it will produce 600 megawatts of power which will supply half of the Railbelt’s current energy needs at a stable or declining rate for the project life of well more than 100 years.
For this reason dams could become a great boost in the hunt for clean energy sources.
Parnell said, “It’s time for Alaska to make the needed investment in renewables that we have in abundance, more than any state in this nation. We're a land of roaring rivers that can generate many megawatts of power to light and heat our homes during the dark winter nights.”
By. James Burgess of Oilprice.com