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37 I ~~~ I~~N I :'::1:: "." ~.-{~~ti!r::~-~~;:~.;hi~:'~.,"- Flat - ~~ ".., 1',<<,' ?:-;:-~~~'.::~:j~;.,~:;. r;'~?!~l{'-r :~ ./~;~1f~~;t0~~\~..~Ci~ -'-'-- ~l\2~ i1'l~'" :~:~~ ," -'~4 " .' .'. ,," :or. , Angle of TCpose ::..~~.Jif~.::.c~ 340_310 t.W~.;Q~~~ B~~~.~'~.:';,~~ .~. - ~,-'--~, ~:'rv.-~"':f':'-_.. Repo!te Und~rcut F1rcun 5. Range of bank fon_. Frolll T.W. Chamberlin (ed). A'P'D technical Paper 2, Aquatic Survey Termlno!oRY. Brlthh Colulllb!1I Ministry of Environrllent. "lctorl~1 B.C. 30 pllgu. Streambank Cover Streambsnk cover is defined as that "egetaUon 'lIhich projects over the channel width of the stream. It may be described as the percent of the channel width covered and generally is arbitrarily divided into two types: crown cover and overhanging cover. Crown cover refers to vegetation overhanging the stream channel by more thllD one mete~~ above the water surface. Overhanging cover is characterhed by vegetation less than one meter above the water surface. The percent of chann,.l covered is descr1 bed separately (at a point) for each bank's v.!getation coverage, not fo~ the channel itself. Streambank Zones Streambank environments have been divi.ded into the (1) toe l,one, (2) splash zone, (3) bank zone, and the (4) terrace zone (Logan 1979). Tbe position on the streambank of the four zonE'S and plan,ts adapted 1:0 the zones is illustrated in Figure 6. The toe zone is eharacterized as always being inundated. It often supports natIVe-vegetation which preVE!Dts streambank erosion. The splash zone is th.,t portion of the bank between the normal high and low water flows and receives the highest stnss. It is exposed frequently to wave wash, erosive stream currents, ice and debris movement, wet-dry cycles and freezing-thawi.ng cycles. Water depths in this zone fluctuate daily, seasonally, and by location. The bank zonE' is usually above the normal high water level. However, it can be pE~iodically exposed to wave wash, stream currents, ice and debris movement, cLOd traffic by man and animals. The terrace zone is inland from the bank zOne and is usually not subjected to erosive action of the stream. except duri.ng extreme high flows and floods.