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- Lake Tahoe is one of the clearest and
most beautiful large sub-alpine lakes in the world.
- It has a relatively small watershed (800 square kilometers, including the lake) for the size of the lake surface (500 square kilometers).
- Lake Tahoe formed about 2 million years ago due to plate tectonics and a volcanic dam at its north end. It lies at an elevation of 6,225 feet.
- At 1,657 feet, Lake Tahoe is the 11th deepest lake in the world. The average depth is 1,027. It is 23 miles long at it´s longest and 12 miles wide at it´s widest.
- 63 streams feed into Lake Tahoe; only one flows out of it – the Truckee River.
- The lake was naturally clear before European-American settlement, because its watershed filtered contaminants such as sediments and nutrients before they entered the lake.
- The lake was known only to the Paiute Indians until General John Charles Fremont discovered it in 1844.
- Between 1870 and 1900, the forests of the basin were heavily logged for use in mine shafts at the Comstock Silver Lode. Today the forest is only 5 percent old-growth.
- Urbanization of the basin has eliminated 75 percent of its marshes, 50 percent of its meadows, and 35 percent of its stream zone habitats.
- In 2000, government census numbers showed that the residential or year-round population at Lake Tahoe was 56,169 people and expected to grow to about 58,458 by 2010.
- Millions of visitors come to Lake Tahoe, with 23 million visitor-days per year.
- Once nutrients enter the lake, they can fuel algal growth for 25 to 50 years. This algae is the primary cause for the loss in clarity.
- The growth of algae has increased about four-fold since measurements were first taken in the lake 1950´s. The lake is losing an average of over one foot of clarity each year.
- The three main sources of new nutrients entering Lake Tahoe are streams, groundwater, and direct atmospheric deposition onto the lake surface.
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