Livestock facilities in areas of recent heavy rainfall have seen surface runoff from those structures total thousands of gallons of runoff water, and those with dirty water containment ponds should be checking to see if they are in danger of running over.
That is a warning from Mary Keena, North Dakota State University Extension livestock environmental management specialist, who is based at the Carrington Research Extension Center.
Typically, producers are concerned about waste pond levels in the spring and watch them pretty closely, especially since that is the time of year when most of the runoff will occur due to snow melt. These ponds are then forgotten about during the summer, since most are evaporation type ponds, Keena explained.
The ponds should be maintained so they have two feet of freeboard space that allows for a 24-hour, 25-year storm event. If the water level is getting into that freeboard space, plans should be made to pump some of the water out of the containment pond to avoid having the water overflow.
“I haven’t heard of anyone going over yet, which we don’t want to happen for several reasons,” she said. “You never want a discharge you don’t know about. If it leaves your property it is no longer considered ‘contained’ and that is when it is called a discharge. In addition, the flowing water could cause structural damage to the containment pond.”
Keena suggests obtaining a sample of the containment pond water and sending to a laboratory such as AgVise for a nutrient analysis. Even though the nutrient content of the water will be minimal, it is still important to update your nutrient management plan by recording the nutrient content and the amount of water applied through such means as a sprinkler or irrigation system.
“Any time water leaves that pond it should be checked for nutrients,” she stressed.
Keena noted there are not typically a lot of solids contained in a water retention pond – it is different from the manure storage system where the solids and liquids are all together in the liquid manure. She has checked with a few operators of this type of system and they are generally in good shape because the facilities are pumped out twice a year – in the spring and in the fall.
“Allowing your containment ponds to overtop is not only a violation of your animal feeding operations permit, it is also cost prohibitive,” said Rachel Strommen, environmental scientist at the North Dakota Department of Environmental Quality (NDDEQ). “The water leaving the containment pond via a breach may cause erosion that will be costly to fix. Also, when the water leaves on its own accord, it cannot be directed to a safe source (cropland) and can be the source of unnecessary pollution to waters of the state.”
Strommen noted that any water that leaves a containment pond and enters waters of the state via culvert, creek or other waterway is considered an unpermitted release.
If a producer does have an unpermitted release, the NDDEQ must be contacted at 701-328-5210, and will be required to record all weather events that caused the release, date of the release, time of release, location of the release, volume of manure or runoff released and the action taken to clean up and minimize the release.
Keena also suggests producers follow an example of how to determine the account of effluent to apply in the “Containment Pond Management” publication at is available online at https://www.ag.ndsu.edu/lem/resources/useful-publications.
Also, more information is available at your local NDSU Extension agent’s office or at the NDDEQ Division of Water Quality at the following website: https://deq.nd.gov/WQ.