New York Times: At a time when large dams are being taken down, not put up, the state of Alaska is proposing to construct one of the tallest and most expensive hydroelectric dams ever built in North America. The Alaska Energy Authority is planning to build a 735-foot, $5.2 billion structure on the Susitna River in a largely empty south-central part of the state, which is watered by runoff from the arc of the Alaska Range. The dam, designed to generate up to 600 megawatts of electricity, would create a new power...