Rancho Cucamonga

Rancho Cucamonga, CA receives a water quality score of 92/100 (Grade A) based on EPA Safe Drinking Water Information System (SDWIS) compliance data for 1 public water system serving the area.

Rancho Cucamonga's water quality is above the national average, with strong compliance records and low contaminant levels. Residents generally receive clean, safe tap water that meets EPA standards.

Rancho Cucamonga's score of 92 is 2 points above the California state average of 90, and above the nationwide average of roughly 78/100 across all U.S. states.

In the mid-size California city of Rancho Cucamonga, a single water system is responsible for servicing the entire community's needs. Located within a West Coast region defined by varied geology, large urban centers, and Central Valley agriculture, the city relies on its singular utility to navigate these diverse environmental factors. For residents and prospective homebuyers, the municipal water supply achieves an excellent overall quality rating, indicating highly reliable and clean tap water across the area.

Water quality data is sourced from the U.S. EPA SDWIS database and updated quarterly. Learn about our scoring methodology → Read our California water quality rankings report →