Ten percent of the wastewater treated by Clean Water Services is used for irrigation and in area wetlands during the summer months. Biosolids recovered through the treatment process are sold to farmers in the region as fertilizer. Additionally, the Durham Advanced Wastewater Treatment Facility is the first in the nation to recover fertilizer from a natural byproduct of wastewater treatment. In 2007 the Durham facility began working with Ostara Nutrient Recovery Technologies to construct a $2.5 million multi-reactor plant that allows the Durham facility to run part of its waste stream through special reactors that transform potentially damaging nutrients into environmentally friendly fertilizer, which Ostara sells commercially.