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i i r r i 38 Mann Draw is eph~*a~. The ~;G*i*~ arrl readily available ~;~*+* supply i.ri the rharmal is largely due to animal grazing aryl channel bank breakdown. The s ~~*+} supply exceeds the carrying capacity or stream power when the stream does flow. Water quality ~+a*+~a*^~~ carrot be used effectively as meas~~ of potential water quality impacts from land use activities in the permit area. Mann Draw water quality reflects the more significant impacts of cattle grazing, roads, aryl oil production. Ztre non-point saurne water quality from the rtorthesn botaidaxy of the permit area is physicaly insignificant in aaq~arison to the Mann Draw .,rarp.shxt area. Sediment Delivery Ratio (SDRI To evaluate the effects of surface erosion on water quality, it is rie~ssaxy to estimate the amount of eroded material that might be moved from the emdirg site into a receiving stream c3~a*+*+P~ system (Sediment Delivery Ratio) . Unforttmately, the prvoesses wRtidr describe the delivery of exuded materials are less well tmderstood than those for erosion, and data for sediment delivery are Scarce. T4iic 15 made more difficult when WOT'kim with ®h~wr;.i rhanrwlg, Historically, the dPro.+++; *+atiorr of the amount of sediment that reached a stream charurel revolved around the oonoept of delivery ratios (Gottschalk aryl Brame 1950, Monier 1958, Maner and Barnes 1953, Williams and Berndt 1972) . A delivery ratio is the volume of material delivered to a point in the watp,~h~~ divided by the gross erosion estimated for the slopes in the watershed above that point. Values range from zero to one. r~*p*+*~ y, a characteristic relationship of sediment yield to erosion does not exist. Marty factors influence a sediment delivery ratio; if these factors are not uniform frmn one watershed to another, the relationship betereest ~;~++P*+r yield and erosion shows considerable variation (Renfro 1975).