San Diego

San Diego, CA receives a water quality score of 86/100 (Grade B) based on EPA Safe Drinking Water Information System (SDWIS) compliance data for 6 public water systems serving the area.

San Diego'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.

San Diego's score of 86 is 4 points below the California state average of 90, and above the nationwide average of roughly 78/100 across all U.S. states.

Residents and homebuyers in this major West Coast metro area can generally expect reliable, above-average water quality delivered across several distinct systems. Because San Diego is situated in a region defined by large urban centers, varied geology, and California's agricultural activity, managing the municipal supply involves navigating diverse environmental influences. While overall quality marks are solid and reassuring, the minor gap from a perfect rating indicates some room for local optimization. For prospective buyers, this means the tap water is generally dependable, though verifying the specific reports of the utility serving your chosen property is a smart step in the home-buying process.

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 →