A review of Iowa’s precipitation and drought trends in 2022

Drought conditions plagued most of Iowa and much of the Mississippi River basin throughout 2022 — casting concerns over industries like agriculture and river navigation.

A review of the year’s drought and precipitation trends deems 2022 the 25th driest year on record for Iowa, according to a Iowa Department of Natural Resource water report released Thursday. But, thanks to recent rain and snowfall, 2023 is off to a better start.

“January is the driest month of the year, but over the last four days we have received nearly the entire month’s worth of moisture — which is encouraging,” said Tim Hall, Iowa DNR’s coordinator of hydrology resources, in a Thursday press release.

Precipitation decreased, temperatures below average

Increased rainfall drenched portions of the Mississippi River basin last year, sending areas like St. Louis and eastern Kentucky into crisis. But in 2022, Iowa stayed relatively parched compared to previous years.

According to the Iowa DNR report, the state only received about 27 inches of precipitation throughout the year — just more than 8 inches below normal, based on 150 years of observations.

Precipitation was below normal for nine months, particularly during the growing season. The average snowfall from December 2021 into February 2022 was nearly 10 inches below normal. That made it the least snowy winter in two decades and the 23rd least snowy based on 135 years of records.

Spring precipitation and temperatures hovered just below normal. By summer, temperatures were 1.2 degrees above normal. But rainfall lagged behind even more, which continued into the fall.

The average statewide temperature for the year was 47.4 degrees Fahrenheit, which was 1 degree below normal. That made 2022 the 44th coldest year on record.

Drought conditions expanded

At the start of 2022, about half of Iowa was experiencing abnormal dryness or moderate drought. Those conditions were only exacerbated throughout the year, marking the state’s third dry year in a row, according to the Iowa DNR report.

Severe drought crept into northwest Iowa by March, yet spring left most of the state in near-normal conditions. During the summer, however, large swaths of moderate to extreme drought spread around the state.

Northwest Iowa experienced exceptional drought — the most severe category of drought — starting in September. This is only the second time such conditions have appeared in Iowa; the first time was during the 2012-13 drought.

Drought designations peaked on Nov. 1, when 10 percent of Iowa experienced extreme drought, 34 percent severe drought and 44 percent moderate drought.

The most intense period of drought in Iowa within the 21st century occurred the week of Sept. 2012, when exceptional drought affected 2.5 percent of the state. 2012 is the 19th driest year on record.

In July, state officials discussed developing a drought plan that would include a trigger point to call for precautions, such as water rationing.

Water resources depleted, but recovering

With less precipitation from above, state stream flows and shallow aquifers were depleted throughout 2022.

The year started off with above-normal average stream flows, even getting bolstered by spring runoff. But, by the end of the year, they had declined to below-normal conditions — particularly in parts of northwest Iowa, which will remain a concern in 2023, the Iowa DNR said in its report.

Water levels in many of the state’s aquifers — which some municipalities and private wells pull from for drinking water — declined, including those around the Lower Iowa and Cedar Rivers. By the fall, various well and pump contractors reported that they couldn’t meet demand for drilling new wells and dropping well pumps deeper into existing wells, according to the report.

However, by the end of the year, groundwater levels across most of the state began to recover thanks to increased precipitation over the past two months. And soil moisture — which dropped between July and November — is also off to a good start this year.

“The above-normal moisture in the last months of 2022 is good news, but the deficits for the year are still significant,” said Hall of the Iowa DNR. “We need more moisture throughout the winter and spring months to make a significant impact on drought conditions in Iowa.”

Brittney J. Miller is the Energy & Environment Reporter for The Gazette and a corps member with Report for America, a national service program that places journalists in local newsrooms to report on under-covered issues.

Comments: (319) 398-8370; brittney.miller@thegazette.com