With the vast snows of the winter still mostly on the ground and more precipitation expected, some livestock producers might have concerns about the capacity of their manure storage systems. That’s according to South Dakota Cooperative Extension Environmental Quality Engineer/Specialist Erin Cortus, who said the South Dakota Department of Environment and Natural Resources (DENR) has put together a fact sheet on manure management-system practices for wet weather conditions.
“The fact sheet can help producers prevent discharges or flooding of their manure management systems, and it was designed for those producers operating under a South Dakota DENR General Water Pollution Control Permit,” Cortus said. “The fact sheet also includes some important practices for all producers to follow. We want to remind all producers that careful planning now will reduce the risk of manure discharges later.”
The fact sheet Cortus mentioned, “Wet Weather Manure Management System Management Practices, March 2011” is available online. Or ask for help retrieving the document at your county Extension office. Cortus said that all producers should monitor and record the levels of their manure storage systems on at least a weekly basis.
“This is not only a requirement of the General Permit, but it can also help any producer prepare and plan for land application,” she said. “To keep clean water out of manure containment systems, producers should also ensure clean water diversions are in good working order and free of ice.”
Taking this step can prevent ice jams that can cause clean water to come into contact with manure and enter a manure management system, Cortus said.
“Similarly, we’d encourage producers to watch for ice buildup in manure transfer areas like piping between pens and in manure settling channels or sediment basins, so that the manure will flow to areas where it is contained,” Cortus said. “To allow for normal winter operation in open lots, the General Permit allows snow containing some manure to be removed from a feeding operation and to be land-applied on land with slopes less than 4 percent.”
The law requires buffer zones of at least 100 feet be maintained to any drainage, and the department recommends producers follow the Natural Resources Conservation Service Nutrient Management Standard 590.
“That requirement allows no more than 10 percent of the annual solid manure production to be applied in the winter,” Cortus said. “By removing snow from around feed bunks, watering areas, lot areas, and sediment basins, the amount of water the manure containment system will have to handle will be reduced during spring melt.”
Producers whose manure storage systems become full before land-application conditions are ideal can apply excess to wet or frozen land. However, there are application guidelines that lessen the potential environmental impact of this practice.
“This action is preferable to an overflowing manure containment system, but it is important to start watching your fields now so you can determine the best fields available if you have to land-apply manure,” said Cortus. “If applying on frozen or wet soil is the only option, look for the driest fields available that are flat or that have less than 4 percent slope. Consider vegetated or no-till land, and remember to maintain at least a 100-foot buffer zone from any drainage.”
Producers, regardless of whether they are required to have a General Permit, are responsible for discharges from their property. All producers must inform the South Dakota DENR of any accidental discharge within 24 hours by calling (605) 773-3351 between 8 a.m. and 5 p.m. Mondays through Fridays. PD
—From SDSU Extension news release