The peak discharge also exceeded the peak that occurred during the spring snowmelt floods of 1950 and 1979. The peak at Jamestown is unusual because most of the runoff contributing to the peak came from areas in and adjacent to Jamestown. Little flooding was attributed to releases from Pipestem or Jamestown Reservoirs. The extent and damages caused by the flooding were much greater than might be expected on the basis of computed recurrence intervals for peak discharges. During the 1993 flood, summer vegetation increased the resistance to flow, and a higher stage was required to pass a given discharge.
Widespread floods are unusual in North Dakota during the growing season.