Why Flooding in Utah Could Last for Months

Severe flooding that triggered a state of emergency in Utah could last for months. Here's why.

This past winter and early spring, Utah saw record-breaking snowpack levels.

An influx of extremely wet weather descended on the state over winter and into early spring. This boosted snowpack levels up to 26.1 inches of snow water equivalent, the Natural Resources Conservation Service reported at the end of March. This broke the previous high snowpack record seen 40 years ago, Salt Lake City TV station KSL reported.

The increased snowpack levels were a welcome sight as Utah has suffered decades of drought. But now, the snow is melting too quickly, as the weather begins to warm up. This is causing severe flooding. Due to there being such a large amount of snow, the flooding could continue for months as the snow melts into the spring and summer.

A memo from Utah Governor Spencer Cox said that this increased snowmelt is already causing avalanches, landslides, rockslides, mudslides, and "other dangerous conditions."

"We're incredibly grateful for the moisture we've received this winter, but the extra rain and hefty snowpack present increasing flood risks as the snow melts," Cox said in a statement. "By declaring a state of emergency, the state will be better able to tap into reserve funds to support flood response and mitigation efforts. In short, we'll be better prepared for what lies ahead this spring."

Over one million sandbags have been distributed around the state to help people mitigate the effects of flooding.

Utah has been in a severe drought for years, along with much of the southwestern U.S.

The wet weather helped replenish some of the Southwest's most important reservoirs. And water levels at Utah's Great Salt Lake—which reached historic lows in December—have risen due to the rains.

But when an area receives "whiplash" weather such as this—when periods of extreme heat are followed by extreme rain and snowfall—it can cause issues.

When an area has been in drought for so long, water can fail to saturate in the parched ground, meaning it floods instead.

And, when warm weather melts all the snowpack very suddenly, there is too much run-off for the area to cope with.

The wet weather has however, massively helped the state's drought conditions.

A drought map released on April 13 by the U.S. Drought Monitor showed that the drought in Utah had greatly eased with no areas any longer suffering from extreme drought.

In comparison, a drought map from January 10, just three months ago, showed that most of the state was in either a severe or extreme drought. Other areas were in a moderate drought, while small parts were just abnormally dry.

Now, 30 percent of the state has no drought at all.

But this may only be a short-term change.

As the Southwest has been in a drought for so long, experts have warned that it could take years of above-average rainfall to make any lasting change.

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