The purpose of this report is to summarize the mass of data pertaining to high rates of streamflow which has been assembled in Utah over a period of many decades. The pertinent data are presented in tables 1-4 and are summarized by graphs in figures 3 and 4. These data have been collected by the U. S. Geological Survey, usually in cooperation with the State of Utah or with other local or Federal agencies. Some uses for streamflow data are cited, and a few of the conclusions which may be drawn from this report are discussed.