Water Quality Index Score: 76, Fair
The Los Peñasquitos watershed originates in the foothills near Iron Mountain, and includes the communities of Poway, Mira Mesa, Sorrento Valley, and parts of Carmel Valley, Scripps Ranch, and Del Mar. Precipitation and runoff is funneled through Los Peñasquitos Lagoon before reaching the Pacific Ocean. Our water quality results in 2016 were fair, with ammonia and phosphorus the main pollutants of concern. These excess nutrients often enter waterways in runoff from fertilized lawns and waste discharges.
How to read our water quality pie charts: these handy charts are designed to give you a sense of which of the factors we measured contributed to the overall water quality score (the number in the center) for each watershed. The size/color of the pie slice gets larger/warmer with increased frequency and magnitude of deviations from good water quality standards for each indicator.