a sustainable choice
Biosolids are the nutrient-rich organic product of wastewater treatment - a never ending resource. Biosolids return valuable nutrients and carbon to the land. Experience shows that biosolids enrich soils and keep them productive and healthy!
King County's Loop® biosolids are recycled as a fertilizer and soil conditioner in agriculture and forestry, and a portion of our biosolids is composted by a private company and sold as GroCo compost for use in landscaping and gardening.