Lake Tahoe Seasonal and Long-term Summer and Winter Clarity Trend Assessment

Trends in clarity, as measured by Secchi depth, vary between summer and winter seasons. The long- term summer trend is consistently declining, with a noticeable cyclic pattern. Winter clarity is showing a different long-term trend. The ongoing summer clarity decline effectively offsets improvements in winter, confounding average annual clarity restoration efforts. The cause for the diverging seasonal clarity trends has not been well documented. This project conducts analyses of the watershed and in-lake monitoring data to evaluate drivers of seasonal clarity conditions.