Download a free copy of the Adobe Acrobat Reader. MF-1168 Applying municipal sewage sludge to agricultural land has been practiced in the United States for several decades. Most Kansas communities regularly use land application as a sludge disposal method, with benefits for both the wastewater utility and the agricultural producer. However, because of new regulations governing the application of sludge to land, many questions are being asked by farmers, utility managers, government officials, and consultants about this alternative. This publication provides information to help answer questions and evaluate this option.
Sewage sludge is the biological residual produced during the treatment of sewage wastewater.
Sludge, more recently being called biosolids, is the solid portion removed from wastewater during the process and might be no more than 1 percent of the wastewater flow. Characteristics of the sludge depend on the wastewater treatment process and sludge treatment. As solids increase, the sludge thickens. Normally a sludge with over 10 percent solids will not flow by gravity through a 6-inch pipe. Sludge becomes a wet semi-solid in the range of 20 to 30 percent solids.