Water Quality Index Score: 70, Fair
The Otay watershed is the southernmost watershed we monitored this year. The portion of the watershed drained by the Otay River includes parts of unincorporated San Diego County, Chula Vista, and San Diego before the river reaches the southern end of San Diego Bay. Both types of indicator bacteria were frequently elevated and were the main contributor to the “Fair” grade in 2016. Nitrate levels were also well above good water quality thresholds, especially towards the end of the year, a trend that has continued into 2017 and we’re keeping an eye on now.
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.