<br />Streambank Erosion
<br />Average Annual Damages in $ Thousands
<br />r--;;~ . ~
<br />PJ,f;C'NM~t~Red'A.,"r-7 New Engl~,,",.
<br />/ '23;600-!. C, I 1,200' L....A'-~-... ~~_qo r!'
<br />,J ,/ 1 1_ \,_:----. ~~,><:~ /-' \1'
<br />'-..-..-_ i ~Upper MISSISSippi T'"' . ''. r \,
<br />1'------- / .. -~ J 5.8(10 .,' I Greal Lakes-/ ',V:;,
<br />( I~--____ .r ~__ '" I \ 2,7~~______,~..
<br />I , .I~-, I ~.I ,-'_', . 'I \-..V'
<br />\ Great Basin\~ ~-r- Missouri BaSin )\;.~.,-~- \ .
<br />'fJ \\ 500 i ---~ 16,600 r I \ /I._.T-s.----::\_
<br />;, .' / r---~~' OhioVallei vi '-~~'
<br />'California / \ L I 5;too-, "' .J~
<br />',;:56,200 \ 1'- -colorado BaSin I I ~ r-- .L- /-;_,Middle Atlantic
<br />N 4Mo-- - ~..,' 10900
<br />. " , --f--'-------.,-T&M8SSeeVaUey ~'-'; ,
<br />") , ~ I ' 900T ~ }'
<br />.. '],' i I I J--, ~r.:: -"
<br />~ I l", Arkansas-Whlte-Red \ '-,_
<br />"I ~',-,-, '93 50g . ~~
<br />-...., _~r-~----,I I' . l
<br />r \ Rio Grande Lower MiSSi~Si~~\ --~-'-\
<br />, 10500 ...,.,38.900:-;:- '..... \ .
<br />1... . '" TexasGulf~'>~~<0 SoutnAtlanllcGul1
<br />" noo 11,~OO
<br />, f' ;'~\I
<br />'~. ~aii '~<>""DI i.-i'
<br />
<br />r--
<br />
<br />/"---..
<br />CAlaskcl
<br />/'-'1~;OOi
<br />Lr-",/;/;~
<br />~/d ;;:~
<br />
<br />U.S. Total = $294,600,000
<br />
<br />Source: U.S. Army Corps of Engineers
<br />
<br />Loss of N alural and Cultural Resources
<br />
<br />All three types of floodplain resources-water, living, and cultural-are
<br />threatened by human use of the floodplain, whether for urban development or
<br />seemingly benign agriculture or forest I)'. Furthermore, because floodplains are
<br />integrated natural systems, tampering with anyone of the component natural
<br />processes may often lead to trouble. Increased runoff resulting from wide-
<br />spread clearing of vegetation, destruction of wetlands, dune removal, paving,
<br />roofing, and other activities can increase flood peaks, stream erosion, and
<br />sediment transfer. Blocking runoff or interrupting the movement of ground.
<br />water can raise flood profiles, increase pollution, and interfere with ground-
<br />water balances and the distribution of sediment. Fertilizers, septic systems,
<br />chemical and petroleum spills, and leached materials from waste disposal
<br />areas can degrade the surface and groundv~:ater resources of floodplains.
<br />Recreational and commercial river traffic often seriously contributes to stream-
<br />bank erosion. Increased sediment can bury food sources and spa\vning areas
<br />and pollution can poison plants, animals, and other living things. Develop-
<br />ment can remove shelter and food, and prevent fish and other wildlife from
<br />moving through their habitat. Erosion of coastal wetlands and filling of \....et.
<br />lands destroys habitat. In many cases, developed floodplains do not have the
<br />aesthetic and recreational attributes of natural ones. Improper agricultural
<br />and forestry practices can be just as destructive of natural floodplain values
<br />as poorly planned urban development.
<br />The nature of the value of natural floodplains makes the damage to them
<br />difficult to quantify, but the losses have been assessed even if no economic
<br />value has been assigned.
<br />
<br />. Over 90% of the United States' coastal barriers are subject to flooding
<br />and erosion because of their seaward exposure, inherent instability, and
<br />relatively lmv-lying topography. In spite of these risks, 14% of the area
<br />of coastal barriers is urbanized (compared to only 3% of the entire
<br />mainland), including Atlantic City, Ocean City, Virginia Beach, and
<br />tvliami. This development also interferes with the natural ability of the
<br />barriers to absorb storm energies, thereby reducing protection for
<br />mainland populations and development as well.
<br />
<br />
<br />
<br />j.'"
<br />The Curps esti7lUlif:s dull in. IN Unilfd States there are
<br />574,500 Tm'ks if stream bank with erosion problems-
<br />142,100 with serious problems. About 78% if all stream
<br />bank erosion Ides place 1.vest of the main. stem if IN
<br />A1isrissippi Rh'er.
<br />
<br />
<br />Hunum o(wpation. and use of a floodpli;in. threatens its
<br />natural resouras in. man] wa)'s. Signifu.:an.t a'llWng these
<br />is tlu poten.tial Jor irureased poilutwn. due to impropn
<br />waste disposal, spillf, and various forms if rwnpoim
<br />foura pollution
<br />
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