Virgin River Basin



Observed streamflow was much above average during the 1998 runoff season. The April through July streamflow volume was 165% of average on the Virgin River at Virgin and 185% of average on the Santa Clara River near Pine Valley.

The 1998 water year started out fairly dry. The October through January precipitation was only 70% of average and the February 1 snow water equivalent was just 80% of average. During February, 215% of the average monthly precipitation fell over the basin bumping the March 1 snow water equivalent to 140% of average. March and April were also wet months. The October through April precipitation ended up at 125% of average and the May 1 snow water equivalent was 195% of average.

The forecast streamflow volumes increased as the seasonal precipitation and snow water equivalent values increased but were still too low. The observed streamflow volume at all of the forecast points was above the forecast 10% exceedance values for February.