Foaming in swine manure pits has become a serious safety concern in the last several years. By reducing pit capacity, foaming manure poses a serious management problem. Even more urgent, however, is the safety threat that foam creates. By trapping large amounts of explosive gas (methane), foam creates the high potential for fires and explosions, especially when the foam is destroyed, such as during agitation and pumping. PLEASE USE EXTREME CAUTION when agitating and pumping, or spraying to reduce foam: maintain ventilation rates and turn off ignition sources, such as pilot lights. Maintain ventilation even when the room is emptied of animals: a number of explosions have occurred when methane concentrations built up after ventilation was stopped as pigs were removed.

Foaming manure spilling out of pumpout

Barn with foaming manure, after explosion. Roof blew off and settled back down.
While some amount of foaming may be typical in manure storages, the type of foam that is currently causing problems is a persistent, occasionally very fast-growing substance that has a mucus-like texture. To see an example of the type of foam we are concerned about click here to view a Youtube video.
We are looking for solutions to the foaming manure. If you have made attempts, successful or not, to remove foam, we are interested! If you would be willing to share your experience with U of MN researchers, please contact Rose at sten0086@umn.edu or call David at 612-625-4262.
If you are a vendor selling a product that aims to reduce foam or inhibit foam formation please send your contact information to David at schmi071@umn.edu and we will add you to the list we are compiling and will shortly make pubic.
Additional Information
- Foaming Manure Pits David Schmidt. Presented to Iowa Manure Applicators January 2011.
- Pit Foaming- What have we Learned? David Schmidt, University of Minnesota, Minnesota Pork Congress 2010 Swinecast.
- Pit Pumping Safety. Jay Harmon, Iowa State University.
- Update on Deep Pit Foaming. Robert Burns, Iowa State University.
- Producer Survey: If you are a swine producer and concerned about foaming and fires please assist University Researchers in their efforts to find solutions to this very serious problem by filling out this short survey.
- Ventilate and Take Other Safety Measures to Prevent Manure Pit Explosions
University of Minnesota, Press Release - Safety Measures to Prevent Manure Pit Explosions
Minnesota Pork Board - Livestock Producers Facing Explosion Hazards with Manure Pumping
Iowa State Extension News Release - Safety Alert—Explosions in Swine Confinement Barns While Pumping Pits(pdf)
Minnesota Grain and Feed Association - Fires and Foam what have we learned?
Iowa Pork Congress/Swinecast., Dr. Robert Burns and Dr. Larry Jacobson - Preparing Swine Barns to Sit Empty
University of Minnesota Extension Service, Mark Whitney - Emergency Ventilation for Hog Barns Brumm (acrobat connect)
Swine Consultancy, Mike Brumm
(PDF Version) - Pit Pumping Guidelines (pdf)
Iowa State University, Mike Brumm and Jay Harmon - Emergency Action Plans (pdf)
Minnesota Pork Board - Printable Door Tags (pdf)
Minnesota Pork Board
