Many irrigated farms dependent upon varying streamflow frequently encounter periods of inadequate water supply because streamflow is inadequate to serve all water rights. Streams fed by mountain snowmelt exhibit sharply peaked hydrographs. During the peak runoff period most water rights can be served. Thereafter streamflow declines rapidly, and many of the later water rights are denied water. Farms that are prohibited from diverting water suffer reduction in crop yields and income. To get the most benefit from varying flow, streams must be closely monitored so that as many rights as possible can be served with the original flow and the return flow that occurs.