RENO, Nev. — Lake Tahoe's clarity last year was the best it's been in a decade and scientists say the continued improvement has them increasingly optimistic that regulating land use throughout the basin and taking other steps to protect the mountain waters are paying off.
Lake clarity averaged 75.3 feet in 2012, an improvement of 6.4 feet from the year before, according to the UC Davis Environmental Research Center and Tahoe Regional Planning Agency.
That's the best it's been since 2002 when the 10-inch white plate called a Secchi disk that is used to measure clarity was visible as deep as 78 feet. It's also a 10-foot foot improvement from the all-time average low of 65.1 feet recorded in 1997-98.
Scientists say the alpine lake's waters were clear enough to see more than 100 feet down back in 1968 before development accelerated in the Tahoe Basin. A steady decline over the next 15 years dropped visibility as shallow to 73.4 feet in 1983.
Stepped up efforts to protect the lake over the past decade and a half have ranged from banning certain jet skis that dump excessive fuel in the waters to regulating construction to minimize soil erosion and improving roads that add to runoff and promote algae growth, one of the biggest threats to clear waters.