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loss of summer water tables. valley bottoms situation. This paper collates and evaluates information relating to streamflow increases after events in small valley bottoms. Relationships between streamflow and valley-bottom conditions are discussed. New research and mangement approaches which might lead to "win-win" solutions for both live- stock and wildlife, are suggested. streamflow (Winegar, pers. conun. 1982), and The result has been localized reductions in for both wildlife and livestock; definitely also in lowered the value of a "lose-lose" INFORMATION REVIEW Reported summer streamflow increases deal with streams of orders one through four. Increased summer flow in ephemeral or intermittent stream channels may result in reductions in the time a stream stays dry, or in devel- opment of perennial flow. Increased summer flow does not necessarily imply increase in annual water yield. Through improved storage, reductions in yield during high flow and increases in yield during low flow may both occur, and result only in a more uniform annual flow regimen. Three types of modification along small, western streams have led to summer flow increase; small dam construction, suppression of woody stream- side vegetation, and the removal of livestock from streamsides. Dams Conversion to perennial flow has been reported as a result of check dam construction in four watershed improvement projects; one in New Mexico (Jester and McKirdy 1966), one in Oregon (Anon. 1979), one in Texas (Brown 1963), and one in Colorado (Heede 1977). The best-documented case was in Colorado in the Alkali Creek drainage. The drainage was fenced and cattle excluded in 1958. In 1963, check dams were installed in ephemeral gully networks for erosion control and disturbed areas were seeded. In 1967, livestock were reintroduced at a low stocking rate. In 1970, the rehabil- itated gullies unexpectedly developed perennial flow (Heede 1967). Evi- dence of prior beaver activity in the drainage was noted at the time of con- structionf and since. 1977 beaver have reoccupied the drainage (Heede, pers. conun. 1983). Precipitation remained normal during the term of the study. Increases in grass cover and new sediment deposits in the gullies (increasing water storage within the channels) were believed to be respon- sible for change to perennial flow. willows and rushes had become firmly established by 1977. Rigorous scientific study on the effects of beaver dams on summer streamflow in the west is lacking, but the observers agree that beaver dams can reduce peak flows and enhance summer flows (Smith 1938, Rassmussen 1940, Tappe, 1942, Wire and Hatch 1943, Grasse and Putnam 1950, Grasse 1951, Denny 1952, Yaeger and Hill 1954, Call 1960, Bates 1963, Call 1970). Streamside Vegetation Conversion to perennial flow has been reported upon removal of valley- bottom vegetation in three western studies; one in Oregon (Winegar, pers. 67