Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Watershed Sciences

Department name when degree awarded

Forest Watershed Management

Committee Chair(s)

George E. Hart


George E. Hart


The influence of aspect on water yield variability over a long period, 1936-1964, was studied at two small, mountainous watersheds within the Davis County Experimental Watershed near Farmington, Utah.

North-facing Miller Creek is densely vegetated by a conifer-aspen forest and mountain brush. Miller Creek's yield was more variable for daily, monthly, seasonal, and annual flows than yields from south-west facing Halfway Creek which is covered by mountain brush. Differences between watersheds in annual yield and snowmelt season runoff were nonsignificant.

The snowmelt runoff season extended for an average of 65 days on both watersheds, but it began 24 days earlier (March 29) on Halfway. Approximately 57 percent of the mean annual flow of 19.4 inches on Halfway, and 68 percent of Miller's mean annual yield of 17.9 inches occurred during the snowmelt runoff season.

One-third of Halfway's annual flow and one-half of Miller's occurred during the May 15 to September 15 growing season when only one-fifth of the annual precipitation of 42 inches usually fell. The difference between the growing season flows from the two watersheds was significant, with Miller's flow greater by 3.4 inches.