Fresno State University’s campus dairy has partnered with Chilean company BioFiltro to clean up wastewater, with the help of earthworms. Wastewater from the dairy runs to a pool of wood shavings, which the earthworms eat while depositing their own castings, removing nutrients.

The company is testing nitrates, nitrogen and phosphates to show progress in the process. Today, the pilot plant filters just 15 percent of the water. The color of the water is visibly cleaner, according to Fresno’s KFSN, but still a light brown due to the woodchips.

The company is working with both dairies and USDA-NRCS to help clean water on dairies that can be used for irrigation.

Source: KFSN, The Fresno Bee