Winter Snowpack

January snow measurement indicates water content normal.

January 5, 2000

Winter snowpack builds in Little Cottonwood Canyon.

The snowpack building in Utah’s mountain ranges is critical for farmers and municipal drinking water suppliers who depend on the amount of water content in the snowpack for the coming year’s water supply.  While most of the valley’s along the Wasatch Front receive about 16-inches of annual precipitation, the higher mountain elevations receive as much as 60-inches of water. Not only is the water content in the snow important to water users, it is also used to predict spring run-off and the potential for flooding.

Hydrologists Dan Schenck and Larry Alserda make monthly measurements during the winter to determine the depth of snow, density and water content in the snow.  This information is used to help predict next summer’s water supply and alert flood control personnel of the potential for snowmelt run-off and potential flooding as the water flows from the mountains through urban areas. Twelve different snow courses are measured at the beginning of each month, beginning in December. The data collected includes the depth of snow, water content in inches and the percent of historic normal for a particular month of the year. 

Automatic SNOTEL measuring equipment is located throughout the State of Utah providing continuous measurements. This equipment provides the data for the remote drainage basins.

Salt Lake City has been conducting snow measurements for over 80 years. In the early years, the time necessary to complete the survey was many days.  Today it is usually completed in several days. Snowmobiles, and on occasion a helicopter, have been used to get deep into the back country.

According to Dan Schenck, the January 1, 2001 snow measures were about normal for this time of year. “Densities are running very high for this time of year which is an indication that the pack will melt at a slow rate this coming spring,” says Dan. “The snow water content that we have currently will guarantee us at least not a severe drought if we did not receive any more snow.” At this time of year about 40 percent of the snow pack has accumulated, with March typically receiving the highest amount of snow and water content. The snowpack will build until temperatures warm and spring run-off begins. This generally begins in late April or May.

On January 1, 2001, the highest water content measured was at the 8,800 foot elevation Alta Central snow course with 14-inches of water.  This site also contained the deepest snow at 44-inches. In a normal year, the water content at this site will accumulate to over 50-inches by May . The lowest measurement was at the 5,500 foot elevation Hidden Springs snow course in City Creek with 3.5-inches of water and a snow depth of 13-inches. The oldest snow course located at the Brighton Cabin, Big Cottonwood Canyon, had 11-inches of water with a snow depth of 41-inches, which is 95.7 percent of normal.

The snowpack can contain as much as 60 inches of water at the higher elevations.

The snow survey indicates that over the entire seven Wasatch Canyon watershed that the snowpack is 99 percent of normal above 7,500 feet; 99.4 percent below 7,500 feet and the average along the Wasatch Front is 99.2 percent of normal.

U.S. Department of Commerce, Natural Resource Conservation Service SNOTEL data  indicate that the snowpack water content in the Provo River Basin is 69 percent of normal; Weber Basin 77 percent of normal and the Duchesne River Basin 92 percent of normal.  These measurements are used to predict the run-off into Jordanelle and Deer Creek reservoirs, both major stored water supplies for Utah and Salt Lake Counties.

A complete record of snowpack measurements can be found on this web site at: www.slcclassic.com/utilities/snow_survey.htm