How long have biosolids been in use?

The use of sewage wastes is not a new concept. For thousands of years, Chinese society returned sewage to farmland to maintain soil structure and encourage plant growth. In parts of Europe and elsewhere biosolids have been applied on agricultural land for more than a century.

In the United States, biosolids recycling is as old as farm reclamation. Today thousands of municipalities across the USA successfully use biosolids. Similarly, biosolids use has been practised in Australia and New Zealand for more than 20 years.