4 C. "The Truth About Dams"

   Setting the record straight.  




  There has been allot of misinformation printed, circulated and reported about dams and fish morality.  Dams are not giant  " Cuisinart " fish blenders that many have alleged and continue to say today.

     This years salmon returns are some of the highest since dams were constructed on the Snake and Columbia rivers.  This is the result of good ocean and weather conditions and the successful use of fish friendly technology used at the dams as well as good hatchery management.  We all benefit from hydropower which is carbon free, clean and annually renewable.  It is the non-polluting environmentally smart electric power source for the 21st century.  No other major power source is storeable and 90 percent efficient and conserves our natural resource by using natural rain water and snow instead of carbon based fossil fuels.  Hydropower  and dams make this all happen.  They have in fact made this country great and are the envy of every other county in the world.  They are the economic engine of the Pacific Northwest, they have won wars by powering aluminum plants for building Boeing airplanes, powering Handford and the production of plutonium for World War II and powering the ship yards and smelters in Portland for the production of ships.  Further more they have made the desert bloom my providing irrigation water and power to the deserts of Washington which creates the irrigated farm land for the production food and fiber for us and the world.   

 The latest scientific data shows that Snake River dams and their fish bypass systems pass 96-98 percent of all salmon safely down stream.  Dams and their hydro turbines are not giant fish blenders like allot of people would like you to believe, they turn at about 86 RPM's ( the speed or a average traveling bicycle wheel ), and they do not kill 95-99 percent of all the Salmon as many suggest.  Almost all salmon are safely bypassed around the dams, by the use of, fish ladders, screens, efficient fish bypass systems, and fish transportation.  The vast majority of salmon avoid the turbines all together.   The remaining fish either go over the spillway or pass through the fish friendly turbines.  For the few fish that actually do go through the turbines, 97-98 percent of them pass safely through fish friendly turbines.  The net effect of all the dams on Snake and Columbia Rivers is a fish mortality of between 2 - 10 percent, averaging about 6 percent, depending upon a multitude of conditions at the particular time.  This loss is more than compensated for by fish hatcheries and improved fish habitat.  When you factor in all the fish friendly technology, fish passage systems and transportation in use today, the fish passage now is better than in a un-damed river.  Today, there are now more fish going downstream and the water is cooler than before there were dams constructed on the Snake and Columbia Rivers.  With all these improvements the in river fish migration survival is better now then before dams were constructed on the Snake and Columbia Rivers.

     The other issue that should be addressed is the natural fish mortality rate in a natural river with falls and rapids which is un-damed.  People that were here before the dams were built, will tell you that down stream from the natural water falls and rapids the river banks would be covered with dead fish that beat themselves to death trying to get over the natural water falls and rapids.   Also they will tell you that during droughts and low water years there were many times that the Snake river would not have enough water in it to maintain stream flow and that trapped and stranded fish died by the thousands in stagnant pools of still water.  The truth is that the dams help maintain river flow from their reservoirs and make it safer, faster and easier for the fish to get back to their spawning areas.  We now know " that the survival of salmon through dams today is not significantly different than the survival through a un-damed river, and that listed stocks face virtually no likelihood of extinction".   


     It should also be noted that dams exhibit their biggest assets during extreme weather events of flooding and droughts.  During flooding events the dams help regulated and store flood water which helps prevent these flooding events from being more damaging that they would be if there were no dams on the rivers.  During droughts the dams reservoirs work to help store and regulate water for irrigation and municipal water districts that may otherwise dry up during droughts.  This helps communities and irrigated farmers up to 300 miles away by continuously recharging underground aquifers for wells.  These two benefits alone protect the health and welfare of many of the residents and farmers of Washington, Idaho and Oregon.












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