Lake clarity improves slightly from 2019 Submitted to The Union Scientists from the UC Davis Tahoe Environmental Research Center determined Lake Tahoe’s clarity improved slightly in 2020, averaging 62.9 feet during the year. | UC Davis Tahoe Environmental Research Center / Katherine Kerlin Lake Tahoe’s water clarity measurements, which are indicators of the health of the watershed, averaged 62.9 feet through 2020, the UC Davis Tahoe Environmental Research Center and the Tahoe Regional Planning Agency announced earlier this month. Lake Tahoe’s clarity peaked in February 2020, when it was deeper than 80 feet. It was at its lowest in mid‐May, when it measured slightly more than 50 feet. These readings were within the average range of the last decade.