Inland Empire Regional Composting Facility

12645 6th Street
Rancho Cucamonga, California 91739

The Inland Empire Regional Composting Facility (IERCF) was constructed in 2007 under a Joint Powers Authority (JPA) agreement between the Inland Empire Utilities Agency (IEUA) and the Los Angeles County Sanitation Districts (LACSD). The IERCF, located in the city of Rancho Cucamonga, is completely enclosed to control odors to meet stringent air quality regulations and is the nation’s largest indoor biosolids composting facility.

The IERCF uses the Aerated Static Pile composting process to recycle over 200,000 wet tons/year including dewatered and stabilized biosolids from IEUA and LACSD’s wastewater treatment processes, as well as wood waste from local communities. It produces over 230,000 cubic yards of high-quality compost each year for local landscaping and horticultural use. The composted product, which is marketed as SoilPro® Premium Compost, is sold as a soil conditioner which helps improve water retention, resulting in better plant growth and water savings.

The facility consistently operates at its design capacity, receiving nearly 800 tons per day of biosolids and recycled waste products.

To learn more about IERCF, please visit the Inland Empire Regional Composting Authority’s website at