Biosolids are the highly treated, safe, nutrient-rich, organic material derived from the wastewater treatment process. Biosolids have many benefits when recycled.

CASA’s biosolids program was launched in 2003 to provide proactive biosolids management leadership in the State of California. The mission of the biosolids program is to:

  • Promote environmentally sound recycling of biosolids.
  • Foster cooperation among governmental agencies, regulators, private corporations, the agricultural community, and the general public in the management of biosolids.
  • Develop and maintain a system of sharing up-to-date, accurate, science-based biosolids information with CASA member agencies, local, state and federal regulatory agencies, and the general public.
  • Identify and support appropriate university research to add to the scientific base for regulations and to stay up to date on research to respond to questions and concerns about biosolids.
  • Advocate against county biosolids recycling land application bans, and help members minimize biosolids management costs while advocating environmentally sound biosolids practices that benefit the people of California.

Fact Sheets

Biosolids 101 for Agency Managers, Directors, and Staff

March 7, 2022



Key Regulations & Issues

WEF Convening


Central Valley Salts Policy: Summary of Implications for Biosolids
April 16, 2020
Contact Greg Kester (gkester@casaweb.org) for Additional Information: 916-844-5262




Final proposal to allow biosolids use and Presentation to Technical Committee – Crops in Cologne, Germany 9-11-18


8-24-22 Wastewater-Solid Waste-Regulatory Sector Seventh Meeting

5-5-22 Wastewater-Solid Waste-Regulatory Sector Sixth Meeting

2-13-19 Wastewater-Solid Waste-Regulatory Sector Fourth Meeting

10-15-18 Wastewater and Solid Waste Sector Meeting

7-12-18 Wastewater and Solid Waste Sectors Presentations

Reclamation Projects

Fire-ravaged Land Reclamation

Superfund and other Mine Sites


Comment Letters