Utah's mountain soils are wetter than they've ever been at this point in fall, and the numbers have Wasatch Front canyon communities watching closely.

Statewide soil moisture entered Nov. 2 at nearly 78% saturation, based on readings from 144 mountain monitoring sites, the Deseret News reported. The figure is roughly four percentage points above the normal peak during spring snowmelt, when soils are typically at their wettest.

That matters for Millcreek Canyon.

"We're kind of in uncharted territory," Jordan Clayton, a hydrologist for the Natural Resources Conservation Service (NRCS) and director of the Utah Snow Survey, told the Deseret News.

What's behind the spike

The record reading follows what is expected to be one of Utah's wettest Octobers on record. Some Wasatch, Uinta, southwest and southeast mountain sites received close to 10 inches of precipitation in October, according to the Deseret News. Mountain precipitation landed in the 98th percentile, and 20 NRCS sites recorded their wettest October ever. Another 22 posted their second-wettest.

Current soil moisture is about five percentage points above this past year's spring peak. It sits only four points below the highest level in the 20-year modern measurement record, set when 2023's record snowpack melted, according to the Deseret News.

The high moisture has already caused problems. Flash flooding, landslides and rockslides hit parts of the state in October, the Deseret News reported. In Big Cottonwood Canyon, flooding and debris restricted uphill traffic on SR-190 on Oct. 11, according to KUTV.

Spring outlook is uncertain

High fall soil moisture means snowmelt runs off more efficiently in spring, feeding the system that supplies about 95% of Utah's water, according to the Deseret News. But whether that translates to flooding depends on how much snow accumulates this winter.

Clayton told the Deseret News that the impending snow collection season is important in learning what happens when soil moisture is this wet in fall. He noted that soil moisture data wasn't collected in 1983, when a record-wet fall combined with record-high snowpack to produce widespread flooding and landslides across parts of the state.

That year, Salt Lake County alone tallied 1,500 damaged sites at an estimated $34 million in costs, according to the Seven Canyons Trust. Statewide damage reached an estimated $200 million. Salt Lake County was among 12 counties that received federal disaster status.

The National Oceanic and Atmospheric Administration (NOAA) winter outlook, released Oct. 15, places the Intermountain West in "equal chances" for below-average, near-average or above-average precipitation from December through February. Long-range models appear to favor moisture lingering through at least November, but above-normal temperatures could factor into snow levels, the Deseret News reported.

Last year's soil moisture was also strong in fall and winter, but Utah collected its worst snowpack on record, leading to poor reservoir inflows.

What Millcreek residents can do

Millcreek's preparedness resources page lets residents check whether their property sits in a floodplain using the city's online maps. Sandbags are available at no cost, up to 25 per household, at the Salt Lake County Public Works Yard at 604 W. 6960 S. in Midvale.

Residents can report flooding to Millcreek at 801-214-2700 during business hours or 385-468-6101 after hours. Chris Catalano, the city's emergency manager, can be reached at 801-214-2715.

Salt Lake County Flood Control advises residents along streams to keep yard debris away from banks. Branches, grass clippings and firewood can block culverts and bridge crossings when water rises, causing flooding and bank erosion.

NOAA's next three-month outlook update is scheduled for Nov. 19.