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IA dairy, DNR looking for safe manure application fields

February 19, 2016, Decorah, IA – A dairy producer about 11 miles north of Decorah contacted the Iowa Department of Natural Resources recently seeking permission for emergency winter manure application.

The producer was building water holding tanks at when he discovered a leaking water line had nearly filled his manure storage structure. He pumped some to another storage area, but still needs to land apply about 600,000 gallons of diluted manure to get by until spring.

Working with DNR’s Manchester field office, several fields from the operation’s manure management plan have been identified for potential emergencies.

“[He] plans to apply manure this week, but it will depend upon field conditions,” said Brett Meyers of the IA DNR. “It’s important to pick relatively flat fields with no underlying tile intakes, and avoid applying before a rain.

“He did everything right by preplanning for an emergency, notifying us and reviewing the plan to ensure the fields meet state requirements and have a low risk of runoff,” Meyers added. “Still, it’s a reminder for other producers to check for water leaks and inspect pits regularly to make sure they have capacity over winter.”

The dairy farm is in an area where soils are shallow over bedrock. Snow cover and frozen ground prevent injecting or incorporating the manure, increasing the chances for runoff to reach a stream. Meyers will inspect crop fields after manure application starts, looking for any problem areas.

Except in an emergency, producers with 500 or more animal units in confinement (totally roofed) buildings are prohibited from land applying liquid manure between Dec. 21 and April 1 if the ground is snow-covered, and between Feb. 1 and April 1 if the ground is frozen.

In an emergency, producers must notify their DNR field office before application and are limited to applying manure to fields listed in their manure management plan that have slopes less than four percent, a phosphorus index of less than two. Any tile inlets in the field must be plugged during and for two weeks after application.