Currently, the snow water equivalent (SWE) in the Farmington hills is greater than it was in 1983, the year of Utah's big flood.
However, there are several differences between the snowfall in Davis County so far this year and the events that led up to the mud slides and flooding in the spring of 1983.
The years 1981-1982 were very wet, breaking many records. State records show that September 1982 received 10 times the normal amount of moisture.
September 2003 was mostly dry, by contrast, as was most of the year. And the only serious precipitation that fell during the fall came in the Christmas storm.
Going into spring, Utah is much drier than it was in the year that four-foot mud rivers cut through Farmington. According to Dave Adamson, director of public works for the county, Northern Utah would still need to receive massive amounts of snow, the snow would need to remain late into the season and there would need to be a rapidly warming spring for a repeat performance of 1983.
By May 21, 1983, there were nearly 57 inches of SWE above Farmington. Late May temperature days were well above average. Memorial Day 1983 was 90 degrees.
One month later there were only seven inches of SWE above Farmington.
Adamson said that 200 years from now, people will still look back on 1983 as an anomaly.
"A whole bunch of variables had to work together to make [the floods of] 1983. The stars aligned to make it happen," Adamson said, explaining that everything leading to the mud slides was very uncommon.
William Case, writing for the Utah Geological Survey, said, "Debris flows may be generated when hillside . . . material becomes rapidly saturated with water and flows into a channel. Intense rainfall, rapid snow melt, or higher levels of ground water flowing through fractured bedrock triggers the movement."
For now, the water on the foothills is frozen, and the ground underneath relatively dry compared to this time in 1983.
But the Farmington Fire of last year may have changed the equation.
Root systems and grasses help hold and secure dirt and rocks. Though the fire did not completely destroy the vegetation, it was badly damaged.
In preparation for this year, officials reseeded the burned foothills with healthy grass. The new grass serves both to prevent mud slides and to stave off the growth of "cheat grass," a weed that dies off in the summer, potentially increasing the fire danger for this year.
Three monitoring stations in the Farmington hills constantly monitor accumulated precipitation, snow depth, SWE, soil temperature, and temperature.
Adamson says the only sure thing to do is watch and monitor.
"If something's going to happen," he said, "this time we'll probably know weeks in advance."
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