Lake Tahoe is one of the world’s most beautiful yet vulnerable
lakes. Renowned for its remarkable clarity, Tahoe straddles the
Nevada-California border, stretching 22 miles long and 12 miles
wide in a granitic bowl high in the Sierra Nevada.
Tahoe sits 6,225 feet above sea level. Its deepest point is 1,645
feet, making it the second-deepest lake in the nation, after
Oregon’s Crater Lake, and the tenth deepest in the world.
John R. Teerink (1921-1992) was the director of the California
Department of Water Resources (DWR) from 1973-1975 during
Governor Ronald Reagan’s administration.He had various lead roles
in the implementation of the State Water Project during his
29-year career at DWR. He progressed through the ranks as junior
engineer, assistant chief engineer and then deputy director until
his appointment to head the department.
A tributary is a river or stream
that enters a larger body of water, especially a lake or river.
The receiving water into which a tributary
feeds is called the “mainstem,” and the point where they come
together is referred to as the “confluence.”
Trihalomethanes are the most common type of “disinfection
byproduct,” which is a substance created from the treatment
of water with organic matter.
How They Form
Chlorine is the most popular water disinfectant, used widely
since the beginning of the 20th century to kill viruses and
microorganisms in water. It has had a major role in significantly
reducing global instances of cholera and typhoid given its
effectiveness and relatively low cost.
Though seemingly a long-way from California’s Central Valley, the
Trinity Dam helps supply irrigation water for Valley farmers and
for hydropower production.
Constructed in the far northwest of California in the 1950s,
Trinity Dam and Lewiston Dam, just downstream, increased the
storage capacity of the federal Central Valley
Project by more than 2.5 million acre-feet.
From it headwaters high in California’s Sierra Nevada, the
Truckee River flows into and through Lake Tahoe, continuing down
the Truckee River canyon to the Reno metropolitan area and then
across miles of Nevada high desert before flowing into Pyramid
Lake, 40 miles northeast of Reno.
The river’s 145-mile course takes it from alpine forests to high
desert sagebrush. (The portion of the Truckee that begins in
California in the Sierra Nevada and flows into Lake Tahoe is
called the Upper Truckee River.)
Until the early 1900s, Central
California’s Tulare Lake naturally appeared every winter as the
southernmost rivers flowing out of the Sierra Nevada filled the
dry lakebed with rainfall and melted snow.
In the spring, the shallow lake near Visalia could cover as much
as 790 square miles, or four times the surface area of Lake
Tahoe. By the end of the hot San Joaquin Valley summer, however,
the giant lake – once the largest freshwater body west of the
Mississippi River – could disappear primarily due to evaporation.
The Tuolumne River is one of the major tributaries draining the
western Sierra Nevada.
Beginning high in the mountains of Yosemite at 13,000 feet, the
Tuolumne River forms at Mt. Lyell, flows through Tuolumne
Meadows, and cascades through canyons including the Grand Canyon
of the Tuolumne , as it descends 150 miles into the San Joaquin
Valley. There, the Tuolumne empties into the San Joaquin River.
The water helps irrigate the agriculturally-rich region,
particularly Stanislaus County. The dam at Don Pedro Reservoir
near Turlock is also used to generate electricity.