UC Davis scientists say clarity last year hovered around the same range it’s been the past five years after showing a marked decline in previous decades. Researcher Geoff Schladow says it’s good news. 

"Well it indicates that we may have turned the corner at Lake Tahoe. It really looks like we may be on the right track now." 

UC Davis scientists say the lake's waters were clear to an average depth of 72 1/2 feet in 2005, a slight change from the year before.

Scientists believe the fine particles of soil and nutrients that fuel algae growth are causing the loss of clarity. The pollutants enter the lake through erosion, runoff and atmospheric deposition.