The Tahoe Environmental Science Center of UC-Davis is responsible for producing State of the Lake Reports every 5 years.  This report is an excellent description of the state of the Lake Tahoe Basin and watershed.  You can find it at: http://terc.ucdavis.edu/stateofthelake/index.html

State of the Lake Report

(August 31, 2010)

The University of California, Davis, has conducted continuous monitoring of Lake Tahoe since 1968, amassing a unique record of change for one of the world’s most beautiful and vulnerable lakes.

In the UC Davis Tahoe: State of the Lake Report, we summarize how natural variability and human activity have affected the lake’s clarity, physics, chemistry and biology over that period. We also present the data collected in 2009. The data shown here reveal a unique record of trends and patterns – the result of natural forces and human actions that operate over time scales ranging from days to decades. These patterns tell us that Lake Tahoe is a complex ecosystem, and it behaves in ways we don’t always expect. While Lake Tahoe itself is unique, the forces and processes that shape it are the same as those that apply in all natural ecosystems. Consequently, Lake Tahoe provides an analog for many other systems both in the western US and worldwide.