Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Civil and Environmental Engineering

Committee Chair(s)

Gaylord V. Skogerboe


Gaylord V. Skogerboe


The effect of irrigation efficiency upon the water demand for agricultural purposes in the Utah Lake drainage area has been evaluated in this study . Irrigation demand is the quantity of water at the supply source necessary to satisfy crop water requirements, taking into account irrigation efficiency.

The Utah Lake drainage area was divided into hydrologic subareas and districts to facilitate analysis. The demand, surplus, and deficit quantities for each area was determined. The computations were made using constant mean quantities. Within a given area, the diverted water was assumed to be applied uniformly to satisfy agricultural crop demands, and the contribution of groundwater was neglected.

The quantity of major interest is the surplus or deficit, which has been computed for present and potential future irrigation effiencies taking into account historical diversions and precipitation, and estimated root zone storage. The crop demand is not adequately met in the study area. There is a surplus in the Provo district (29,000 acre-feet annually), while deficits occur in the Spanish Fork district (69,000 acre-feet annually) and Northern Juab Valley subarea (38,000 acre-feet annually). The common pattern is excessive diversions in May and insufficient diversions in July through September. The present mean irrigation efficiency of 36 percent in the Utah Lake dra inage area results in an annual deficit of 111,000 acre-feet, of which 69,000 acre-feet occurs in Utah Valley. The maximum monthly deficit is 76,000 acre-feet, which occurs in August.

Provided irrigation efficiencies were increased to 68 percent, surplus would exist in every month and the annual surplus would be 159,000 acre-feet. The combination of additional storage facilities to modify the diversion to coincide with crop demand, reallocation of water from water -plenty to water -short areas, and increasing the irrigation efficiency would provide the best economic use of water for the benefit of the area. (169 pages)




This work made publicly available electronically on February 6, 2013.