Design recommendations for milkhouse wastewater treatment systems

Four different types of milk house wastewater treatment systems were installed on fifteen dairy farms in Minnesota. All of the treatment systems had a septic tank for primary treatment. Installed systems include aeration with discharge to tile lines or subsoil infiltration, irrigation to cropland or pasture, a large soil surface infiltration area covered with bark (bark beds),or a recirculating media filtration system with discharge to a subsoil infiltration area. All systems are being monitored for influent waste strength and flow and overall system performance (system performance measures differ with system type). System economics, operation and maintenance are also being documented. Lessons learned from the installation and monitoring of these systems has led to some general guidelines for the selection, design, an installation of these systems.