City of Philadelphia






Biosolids -- Beneficial Use

 

Biosolids are the recyclable material resulting from treatment of wastewater. Approximately 40-50 percent of the 8-9 million tons of biosolids produced each year by municipal wastewater treatment facilities are recycled for beneficial use and reused in a variety of applications, including:

  • Agricultural land used for commercial crop production
  • Landscaping and home gardens
  • Forested areas
  • Public sites, such as parks and recreation areas
  • Disturbed land, including construction and strip-mined areas

Biosolids are managed by a two-tier network of regulations. The federal Part 503 regulations, in conjunction with state regulations, ensure that biosolids recycling is a safe and integral part of this country's water quality and waste management programs.

 

Biosolids recycling returns a useful resource to the environment. Biosolids are rich in nutrients, containing nitrogen and phosphorus along with other supplementary nutrients in smaller doses, such as potassium, sulfur, magnesium, calcium, copper and zinc. Soil that is lacking in these substances can be reclaimed with biosolids use. The application of biosolids to land improves soil properties and plant productivity, and reduces dependence on inorganic fertilizers.

 

Less Disposal in Landfills

In the past, biosolids have been disposed of in landfills and even in the ocean. Now, as more and more treatment plants improve wastewater quality, treated biosolids are an even greater resource to be recycled and returned to the environment. Recycling reduces the volume of waste to be disposed of in limited capacity landfills. And the threat of pollution problems from disposal practices such as landfilling, ocean dumping or discharge to coastal waters is avoided.

 

Benefiting the Land

U.S. Environmental Protection Agency statistics indicate that nearly 50 percent of biosolids are applied to the land. Land application of biosolids takes place in 46 of the 50 states. There are more than 500,000 acres that can receive biosolids under the approval programs in these states. Virtually all land uses are compatible with biosolids application if biosolids are properly treated and their application is well-managed.

 

Copyright @1996 Water Environment Federation.
Internet mail to: webfeedback@wef.org
Adapted by: Philadelphia Water Department, Biosolids Management Unit, 215-685-6248