See the figure for cross section of a dairy waste storage pond. Note the upper pumpdown stake. Pumping should begin when water reaches this level. Cross section of a dairy waste storage pond. Dairy waste solids, particularly those from freestall housing bedding, can accumulate quickly in waste storage ponds.
Solids can cause pumping problems, and over time can greatly reduce usable storage pond volume.
Serious consideration should be given to the installation of solids separation equipment between the freestall housing and waste storage pond. Properly designed gravity settling basins can remove up to 50 percent of the waste solids but must have a minimum of 4 to 6 feet elevation between the bottom of the barn collection channel and the maximum height of the storage pond liquid surface to work properly. They require periodic cleaning out with a tractor front end loader and work best when at least two are constructed side by side to allow alternating use and some manure solids drying out before cleaning. Mechanical separators are typically either rotating or stationary screens and generally remove 20 to 30 percent of the waste solids. These separators require little attention and produce manure solids that may be easily recycled as bedding or land applied off-farm with solid manure spreaders.