DamNation: 'The U.S. obsession with river dams and hydroelectric power'

is not a perfect film, but it's an important one. The film — narrated in a low-key way by co-director Ben Knight — tracks America's love affair with river dams and hydroelectric power — from its progressive, put-people-to-work origins under Roosevelt in the 1930s to its obsession with damming every possible river in the '50s and '60s under the sometimes shaky premises of flood control. The small state of Maine has over 800 dams, to cite one example.

The documentary gives fair screen time for dam proponents to also make their case, but its sympathies clearly lie with the environmental activists, who convincingly make the case that stagnant rivers are dead rivers. Removing dams can restore profitable salmon runs and tourism, aside from the fact that often the hydropower involved could easily be replaced by a few wind turbines. "DamNation" could have gone a bit further with that thread, but it successfully shows how over the past two decades America has been slowly restoring some rivers to their natural state. This will hopefully inspire viewers in concrete-loving Japan, where a vast number of rivers have been dammed, with more dams in planning. As one college professor in the film puts it, "radical ideas can eventually become conventional."