Beneficial reuse of municipal biosolids in agriculture

Abstract

Farmers have known for centuries that animal manures spread on pastures and cropland can improve soil fertility. In the 1920s, farmers began to use sludge from municipal wastewater treatment plants as a fertilizer. Through decades of research, the scientific and agricultural communities have come to understand that municipal sludge or "biosolids" contain valuable nutrients and organic matter that improve the soil in a way similar to animal manures. It is important to understand that biosolids are not raw sewage. Biosolids are organic solids that have been treated to stabilize organic matter and reduce disease-causing organisms or pathogens. This publication was developed to help answer some common questions regarding the use of biosolids and to give farmers benchmarks for good practices.