Deer Creek Reservoir, Utah

 

Except for the higher mountains, most of Utah is very dry and technically a desert. Here is the current definition of a desert from the USGS article "What is a desert?"

There are almost as many definitions of deserts and classification systems as there are deserts in the world. Most classifications rely on some combination of the number of days of rainfall, the total amount of annual rainfall, temperature, humidity, or other factors. In 1953, Peveril Meigs divided desert regions on Earth into three categories according to the amount of precipitation they received. In this now widely accepted system, extremely arid lands have at least 12 consecutive months without rainfall, arid lands have less than 250 millimeters of annual rainfall, and semiarid lands have a mean annual precipitation of between 250 and 500 millimeters. Arid and extremely arid land are deserts, and semiarid grasslands generally are referred to as steppes.

In case you don't automatically convert metric measurements, here are the equivalents: 250 millimeters = about 10 inches and, of course, 500 mm is about 20 inches. Heber Valley where the Deer Creek Reservoir is located gets about 20 inches of rain a year making it right on the edge of the semi-arid definition. Where I live in Provo, we get about 18 inches of rain a year. The U.S. average rainfall across the entire country is about 38 inches of rain a year. However, currently, Utah County, where we live and the location of the Deer Creek Reservoir are both under an Exceptional Drought. The entire state has had less than an inch of rain in the last 60 days.