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Published byJonathan Howard Modified over 9 years ago
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The Willamette River n A look at the River n http://www.willamette- riverkeeper.org/theriver/
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Historically n Wild river. n Floods in winter n 187miles on its main stem n Great floods result in the river changing
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Historically the valley n Valley open prairies n Oak and conifer woodlands n Native American peoples, Calapooia n Euro American 150
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The River Today n Surrounded by agricultural land n Little riverside forests n Cities hug the banks n Industrial facilities n Source and dumping n Harnessed and modified by hydropower dams on the tributaries. n Pollution and habitat destruction have altered the function and very health n Still opportunities to regain some semblance of the river's former health and vitality.
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Physical Character n 13th largest river in the United States n Valley receives between 40-50 inches of rain a year. n Watershed of 11,500 square miles in area. n Average flow of the river is some 32,000 cubic feet per second (cfs) where the river flows into the Columbia. n Flood in February of 1996, the flow was estimated to be some 460,000 cfs.
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Damming of the Willamette n 13 US Army Corps of Engineers, dams on its tributaries. n 11 of which produce hydropower. n Privately held dams n These projects control over 27% of runoff n These projects have a direct connection to the future health and natural function of the Willamette
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Wathershed & Tributaries
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Watershed & Tributaries n Willamette River has multiple tributaries. –Middle ForkCoast Fork –McKenzie, Santiam, –Mary's, Luckiamute, –Yamhill, Molalla, –Tualatin, Clackamas
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The Impact of People n 22% of the Willamette Basin agriculture n 70% forest.due to the mountainous parts n 8% urban. n 70% of all Oregonians live in the Willamette Basin. n Man made north south - Interstate 5.
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Cities n Greatest impact on the river n Major cities hug the river n Providing ample opportunity for polluted runoff n Habitat alteration
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Pollution 1 n Pollution has come from industry n Some from agriculture n Some from cities n Some from other sources as well n 1960s progress made reducing industrial wastes
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Pollution 2 n Non Point Source Pollution –Can not identify the source. n Point Source Pollution –Can put your finger on the pollution.
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Governor Tom McCall n Reduced the raw industrial pollution n Environmental law.
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Current River n River flows that are manipulated by dams, to the detriment of native species. n Habitat destruction on the main stem and tributaries that has resulted in threatened species and rising temperatures.
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Loss of channel diversity n In the early days an intensive effort to cut off natural back channels separated river habitat from the main river. n 90 miles of the river now has banks that were hardened with rip rap. n Instead of multiple braided channels that support local biodiversity, the river is largely confined to one main channel in many areas.
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Current Problems n Clean Water Act 303 (d) list for violations –temperature –bacteria –mercury standards n 40 miles known as the Newberg Pool –high percentages of skeletal deformities.
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Current Problems n A six mile stretch in Portland –Federally designated Superfund –toxic pollution –heavy metals –cleanup process a decade to complete. n Spring Chinook and steelhead, the Willamette's native salmonids, are listed as threatened under the Federal Endangered Species Act.
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Current Problems n Lamprey eel and white sturgeon found to contain man made chemicals in their tissues. n Fish consumption advisory for resident fish.
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