Utah Reservoirs Approaching Capacity With High Snowpack Levels This Year

Jun 12, 2019

The Natural Resource Conservation Service (NRCS) recently released the Utah Water Supply Report for spring, revealing that reservoir levels across Utah are significantly above average this year and approaching capacity. This information is especially important for dam managers and water conservation districts who distribute water to their water users.

This year, the Snow Water Equivalent, which is a measurement of the amount of water in the snowpack, is greater than 90% of measurements recorded over the last 30-40 years. Snowpack measurements are an important predictor for water supplies in Utah.

“In most of the West, and particularly states like Utah, most of the water that we use comes from melted snow," said Jordan Clayton, a hydrologist with NRCS. "We’ve determined that for Utah the number is actually more than 95% of our water is derived from snowmelt-related processes, so it is obviously critically important to know how much water is stored on the mountains in the form as snow."

He said there are some risks associated with the high levels of snow still present in a few high elevation basins in Utah.

“What we were hoping for, in terms of flood risk when you have a big snowpack year, was to see a more gradual release of that stored water, and that’s luckily what we’ve gotten for the most part," Clayton said. "There has been some rapid melt in the last week or so, but that is part of why we reissued an update to our spring forecast report, to address the fact that there’s-- in a few basins in particular--still lingering substantial amounts of snow and also not a huge amount of reservoir capacity to store that water,"

Forecasts for the flow rates of streams contributing water to reservoirs are created using precipitation and snow water equivalent data, but Clayton said the next steps towards improving these predictions could be incorporating soil moisture data. Higher soil moisture improves the efficiency of snowmelt flow because less water will be soaked up by the soils in the basin if they are saturated.