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<br />Ephemeral stream - A st,eam that flows only in di,ect ,esponse to
<br />p,ecipitation and ,eceives little 0, now wate, f,om sp,ings 0, no
<br />sustained supply f,om snowmelt or othe, sources. An epheme,al
<br />st,eam's channel is at all times above the ,..ater table.
<br />
<br />Erosion - Removal of soil particles from the land su,face due to water
<br />or wind action.
<br />
<br />Erosion control matting
<br />placed or sp,ayed on
<br />erosion or providing
<br />estab I i shed,
<br />
<br />Fib,ous matting (e,g, jute, pape" etc,)
<br />a streambank fo, the pu,pose of preventing
<br />tempo,a,y stab i I i zat i Oil unt i I vegetat ion is
<br />
<br />Fabriform - G,out-fi I led fabric mattress used for st,eambank
<br />p,otection,
<br />
<br />Fascine - A bundle of b,ush, sticks, or timbe, used to make a
<br />foundation mat 0, to construct a ,evetment to protect a
<br />streambank against erosion.
<br />
<br />Fence - A streambank protection technique consisting of wire mesh 0,
<br />timber attached to a series of posts, sometimes in double rows;
<br />the space between the rows may be filled with rock, b,ush, or
<br />othe, materials, Fences may be placed either parallel to the
<br />bank 0, extended into the stream, in either case these structures
<br />decrease the stream velocity and encourage sediment deposition as
<br />the flow passes through the fence.
<br />
<br />Fetch - The a,ea in which waves are generated by wind having a rather
<br />constant di rection and speed; sometimes used synonymously with
<br />fetch length.
<br />
<br />Fetch length - The horizontal distance (in the direction of the wind)
<br />over which Wind generates waves and wind setup.
<br />
<br />Fi Iter - Layer of fab,ic, sand, gravel, or graded ,ock placed, or
<br />developed naturally where suitable in-place materials exist,
<br />between the bank revetment and so i I for one more of three
<br />purposes: to prevent the soi I from moving tr.rough the ,evetment
<br />by piping, extrusion, or erosion; to prevent the revetment from
<br />sinking into the soil; and to permit natural seepage from the
<br />streambank, thus preventing bui Idup of excessive hydrostatic
<br />p,essure.
<br />
<br />Flanking - E,osion ,esulting from streamflow between the bank and the
<br />landward end of a rive,-training or a g,ade-control structure,
<br />
<br />Flow slide - Satu,ation of a bank to the point where the soil material
<br />behaves mora I ike a I iquid than a sol id; the, soi Ilwater mixture
<br />may then move downslope ,esulting in a bank failure.
<br />
<br />Gabian - A wicke,wo,k or wire mesh baskat or cage fi I led with stone 0,
<br />other materials placed against a streambank to prevent erosion,
<br />
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