San Diego County, CA

ZIP 91963

In ZIP 91963, 4 of the 12 things we check have at least one part graded D or F.

• Drinking water: Twin Lakes Resort has 2 contaminants at or over an EPA legal limit; 6 contaminants are above health goals, led by arsenic at 2,867× California’s Public Health Goal.
• Closer to Superfund sites than 0% of U.S. neighborhoods, with no listed site within 10 miles of its center.
• Largest share of modeled toxic air from industry: Steris Isomedix Services (97%), mostly ethylene oxide.
• Fine particles (PM2.5) average 5.7 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 344,328 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 91963

• Superfund sites nearbyA
• Factories and industrial sitesA
• Oil and gas wellsA
• Parks and nature nearbyB
• Air qualityA
• Drinking water qualityC to F
• Pesticide useD
• Neighborhood health statusD
• Past wildfire impactsF
• Past flood impactsA
• Noise levelsA
• Radiation signalsC

Based on 1 census tract · compiled September 10, 2026 · how each grade works and its sources

Loading the full report, with every source…