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Damns by Sarah and Allen. JUST KIDDING WE KNOW HOW TO SPELL DAM. How. Disadvantages Case studies. By C lip Art. Why do we build dams?. F rom : http:// www.waterencyclopedia.com / images /wsci_01_img0129.jpg.
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Damns by Sarah and Allen JUST KIDDING WE KNOW HOW TO SPELL DAM
How • Disadvantages • Case studies By Clip Art
Why do we build dams? From: http://www.waterencyclopedia.com/images/wsci_01_img0129.jpg • Dams can store rain water or water directly from the river itself. Then, in case of a Drought, the dam will still have a relatively constant supply of water. • Producing Power. • Controls flooding & provides recreational activities such as boating fishing and swimming, if the lake is not being used for drinking water (Dam Society). • Simple design makes for inexpensive repairs and maintenance costs (Dam Society).
Advantages of Building a Damn From: http://www.waterencyclopedia.com/images/wsci_01_img0129.jpg • Simple design makes for inexpensive repairs and maintenance costs (Dam Society). • Produce inexpensive (after completion) and clean power. • Renewable energy source, because the water is not destroyed by passing through the dam. • If needed, dams can be shut down instantly, where thermal plants take hours, and nuclear plants can take days! (Dam Society). • Very few breakdowns.
River diversion and the Aral sea • Aral Sea in Central Asia. • Evaporation matched by inflows of water from the Amu Darya and Syr Darya rivers. • 1960 building of dams • eliminated the flow of water into the sea MORE INFO From: http://landsat.gsfc.nasa.gov/graphics/img/f0012.jpg
River diversion and the Aral sea • 1995, the area of the Aral Sea was only 30,000 square kilometers, • 1960 64,500 square kilometers. • fishing industry which once supported 60,000 workers halt • 20 of the 24 fish species once caught in the sea have been extinct • bird species found in the Amu Darya Delta had declined from 319 to 168, • the delta forests had died • only 30 out of 70 species of mammals remained. From :http://malaysiafishingtour.com/wp-content/uploads/2010/11/Fresh-Water-Fish.jpg
Sediments & Erosion From: http://www.aperfectworld.org/clipart/Nature/river02.GIF
Sediments & Erosion From: http://www.aperfectworld.org/clipart/Nature/river02.GIF • velocityof the water drops • Sedimentcarried by the river dropped • erosive potential of the river is increased • sediment deprivation affects shoreline processes and biological productivity of coastal regions.
Grand Canyon • Grand Canyon below Glen Canyon Dam –1963 • Erosion of the sediment along the beaches began because of the lack of incoming sediment. • Beaches disappeared!! • 1996 project recovered beaches but was short-lived Want to know more?
From: http://www.aperfectworld.org/clipart/Nature/river02.GIF From:http://1.bp.blogspot.com/_gbzApcV7MwY/SNE64u2XpgI/AAAAAAAAAQI/jCxvHTL0jAI/s400/nemo_4.jpg
Columbia River • averaged between 10 and 16 million fish before non-native settlers first arrived in the 19th century. • 130 or so dams in the basin, • 1.5 million salmon and steelhead enter the Columbia each year Thirsty for more knowledge??!!
Works cited • " Dams - Impact Of Dams - Water, River, Flow, Sediment, Colorado, and Lake ." Science Encyclopedia. N.p., n.d. Web. 14 Apr. 2011. <http://science.jrank.org/pages/1942/Dams-Impact-dams.html>. • "Dams and Migratory Fish | International Rivers." International Rivers. N.p., n.d. Web. 14 Apr. 2011. <http://www.internationalrivers.org/en/node/1639>. • "Hydrological Effects of Dams | International Rivers." International Rivers. N.p., n.d. Web. 14 Apr. 2011. <http://www.internationalrivers.org/node/1640>. • "Hydrology | Carl Renshaw." Dartmouth College. N.p., n.d. Web. 14 Apr. 2011. <http://www.dartmouth.edu/~renshaw/untitled_text/hydrology.html>. • "PROS AND CONS." Sir Francis Drake High School Website. N.p., n.d. Web. 14 Apr. 2011. <http://drake.marin.k12.ca.us/stuwork/rockwater/Upload%20this%20doc--dams%20and%20hydropower%20report/pros%20and%20cons.html>