As builders in China rush to construct dams alongside the Mekong River in southeast Asia, villagers are seeing their fish disappear, their rice fields die and their houses flooded. Though China can really feel removed from residence, the influence of pointless dam building for the only real function of hydroelectric energy era is ubiquitous. These massive dams work to generate hydroelectric energy by harnessing the motion of flowing water to rotate giant generators. Nevertheless, hydroelectric dams not solely trigger flooding within the surrounding land atmosphere however in addition they forestall the free motion of aquatic life and vitamins alongside the river resulting in points with meals, jobs and houses. Due to this fact, constructing these dams poses far larger penalties for the river’s ecosystem — and its inhabitants — than is gained by the renewable nature of hydroelectric energy.
Hydroelectric energy will not be innately dangerous — small generators put in in working creeks or streams might be very efficient in powering particular person properties and even communities with renewable vitality. Nevertheless, it turns into problematic when dams are constructed for the only real objective of hydroelectric energy technology. Within the U.S., hydroelectric dams are extremely prevalent — the nation is dwelling to roughly 2,300 dams with 45 of those located in Virginia. Nevertheless, the key points related to the dams on the Mekong River have additionally impacted communities and ecosystems throughout the U.S.
One of many largest environmental problems surrounding dams is the endangerment and eventual extinction of migratory fish vital in feeding communities and sustaining the aquatic meals chain. Not solely do these dams block their reproductive actions, however in addition they trigger shifts within the nutrient composition and temperature of the water additional impacting fish well being. One widespread answer to permit for upstream motion is the fish ladder — by counting on the fish’s pure capability to leap over rocks, the ladder permits for the fish to scale what is actually a ramp across the dam.
Regardless of the centuries of engineering invested in these ladders, a majority of fish won’t ever attain their spawning grounds, and for the extra torpid fish native to Asia or South America where large-scale dams are being proposed, these ladders will virtually certainly fail.