New standards for manure spreading released by DATCP

New standards have been released for the Department of Natural Resources (DNR) manure spreading restrictions that affect 16 counties where bedrock is especially vulnerable to groundwater.

The new technical standards were published by the Department of Agriculture, Trade, and Consumer Protection (DATCP) and apply to manure spreading on silurian bedrock areas. In those areas, the bedrock of Silurian dolomite rock is overlain by soils of 20 feet or less, according to the University of Wisconsin-Extension, and groundwater is particularly vulnerable to contamination.

By providing a standard, producers now have a process to measure the depth to bedrock for their respective, affected lands

The affected counties include  Brown, Calumet, Dodge, Door, Fond Du Lac, Kenosha, Kewaunee, Mantiwoc, Milwaukee, Outagamie, Ozaukee, Racine, Sheboygan, Walworth, Washington, and Waukesha. “For crop and livestock producers who fall under the requirements of this rule, this technical standard provides science-based methods for confirming the accuracy of depth to bedrock in these areas,” said Sara Walling, DATCP’s agricultural resource management division administrator.

A document outlining the new standards notes that it may be used “for all fields receiving mechanical applications of manure in areas where the mapped bedrock consists of Silurian dolomite with a depth to bedrock of 20 feet or less and where the existing silurian bedrock map information is being refuted.” An entire process is outlined by the new standard, including the stages of a site assessment, as well as various methods of assessing bedrock contamination.

Manure is often used as a nutrient for agricultural projects, and its management has become a cornerstone to the state’s plans for improving water quality. Manure  spills can range from minor to catastrophic, especially if a spill enters a water system. In June, a manure spill of unknown size in Lincoln County resulted in an observable fish kill, according to the DNR. Manure has also been linked to nitrate contamination of Wisconsin’s water supplies. Approximately 7,000 fish were reported as killed due to the Lincoln County spill. The DNR and DATCP are working with the involved farm to address any long-term needs the farm may have.

This article has been updated with additional information regarding the Lincoln County manure spill, provided by the DNR.