A recent story in the online publication Yale Environment 360 reports on the impact of a planned series of dams along Southeast Asia’s Mekong River. A remarkable two-thirds of the world’s rivers have already been dammed. The 2,800-mile-long Mekong was one of the world’s last free-run rivers; that is, until China completed the Xiaowan dam last fall. At 958 feet high, Xiaowan is the world’s tallest dam and the first of eight that China plans to erect along the Mekong. A United Nations report has called these dams “the single greatest threat” to the future of the Mekong river, which sustains the world’s second largest fishery.
The Pasaaic River has three small dams along its length, if you count the modest stone impoundment that maintains historic Leddell Pond in Mendham. The dam above Great Falls in Paterson, designed to hijack the river’s flow in order to power Paterson’s mills and factories, has had the most effect on the river’s natural state. But the impact of dams on the Passaic River has been minimal compared to their impact on the major rivers of the American west – the Columbia, the Snake, the Colorado. For a detailed – and disturbing – chronicle of American dam building and its not so positive effects, read Marc Reisner’s 1989 classic Cadillac Desert.