IA DNR: Recent rain helped to lower water demand, but groundwater levels are unchanged

Ag/Outdoor, News, Weather

August 10th, 2012 by Ric Hanson

The Iowa Department of Natural Resources has released its latest Water Summary Update. Officials say prior to the rains of August 8th, precipitation averaged 50 percent less than normal for the last two weeks. Shallow groundwater levels in parts of Iowa are at or near historic lows. Recent rainfall has helped to lower water demand, but has not impacted shallow groundwater levels. There have been reports in eastern Iowa, of private wells being drilled deeper or having pumps lowered to meet water demand.

The number of streams with “protected flow” (cannot be used for irrigation) have been reduced from 22 to 19. Streams in most of southwest Iowa are below normal flow, and the report shows shallow groundwater in all of southwest Iowa is not enough to meet the demand for irrigation. More than two-thirds of the State are now under Extreme Drought conditions, including every county stretching from northern Boone County southwest, through northwestern Fremont County. Cass County and the northwestern tip of Adair County are included in the Extreme Drought conditions, while the remaining southwest and south central counties are under Severe Drought conditions.

The past two weeks continued to be mostly hotter and drier than normal weather across Iowa. Temperatures averaged 4 degrees above normal while precipitation averaged 0.60 inches less than normal for the period. Rain totals varied from no rain at Underwood in western Iowa to nearly four inches at Nevada through August 6th. Storms on August 8th (after the cut-off time for the drought
monitor and for the precipitation map) resulted in a statewide average of 0.34  inches of rain, with almost everyone in the state seeing some rain. Among the areas with the most rain, was Audubon, Harrison, Page, and Shelby counties.

For a more thorough review of Iowa’s water resource trends July 23 through August 8, go to http://www.iowadnr.gov/watersummaryupdate. The report is prepared by the technical staff from the Iowa DNR, the Iowa Department of Agriculture and Land Stewardship, and the USGS, in collaboration with the Iowa Department of Homeland Security and Emergency Management Division.