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Lake Tahoe
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Lake Tahoe is a large freshwater lake in the Sierra Nevada mountains of the United States. It is located along the border between California and Nevada, west of Carson City, Nevada. Lake Tahoe is the largest alpine lake in North America. Its depth is making it America's second-deepest, (Crater Lake, in Oregon, being the deepest at 1945 feet (594 m) deep).
The lake was formed about 2 million years ago and is a part of the Lake Tahoe Basin with the modern Lake being shaped during the Ice Ages.
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Encyclopedia
Lake Tahoe is a large freshwater lake in the Sierra Nevada mountains of the United States. It is located along the border between California and Nevada, west of Carson City, Nevada. Lake Tahoe is the largest alpine lake in North America. Its depth is making it America's second-deepest, (Crater Lake, in Oregon, being the deepest at 1945 feet (594 m) deep).
The lake was formed about 2 million years ago and is a part of the Lake Tahoe Basin with the modern Lake being shaped during the Ice Ages. The lake is known for the clarity of its water and the panorama of surrounding mountains on all sides. The area surrounding the lake is also referred to as Lake Tahoe, or simply Tahoe.
Lake Tahoe is a major tourist attraction for both California and Nevada. It is home to a number of ski resorts, summer outdoor recreation, and tourist attractions. Snow and skiing are a significant part of the area's economy and reputation. Mountain and lake scenery are attractions throughout the year. The Nevada side also includes large casinos. Highways provide year-round access from Reno, Carson City and Sacramento.
Geography
Lake Tahoe is the second deepest lake in the United States, with a maximum depth of , trailing only Oregon's Crater Lake at . Tahoe is also the 16th deepest lake in the world, and the fifth deepest in average depth. It is about long and wide and has of shoreline and a surface area of .
Approximately two-thirds of the shoreline is in California. The south shore is dominated by the lake's largest city, South Lake Tahoe, California, which adjoins the town of Stateline, Nevada, while Tahoe City, California is located on the lake's northwest shore. Although highways run within sight of the lake shore for much of Tahoe's perimeter, many important parts of the shoreline now lie within state parks or are protected by the United States Forest Service.
Natural history
Geology
The Lake Tahoe Basin was formed by a geologic block (normal) faulting about 2 million years ago. A geologic block fault is a fracture in the earth's crust causing blocks of land to move up or down. Uplifted blocks created the Carson Range on the east and the Sierra Nevada on the west. Down-dropped blocks (a graben) created the Lake Tahoe Basin in between.
More technically, Lake Tahoe is the youngest of several extensional basins of the Walker Lane Deformation Belt that accommodates nearly 12 mm/yr of dextral shear between the Sierra Nevada Microplate and North America. The Lake Tahoe basin is formed by a series of large down-to-the-east normal faults, including the West Tahoe—Dollar Point fault, Stateline/North Tahoe fault and the Incline Village fault. These right-stepping en-echelon faults are capable of large magnitude 7 earthquakes, with the most recent M7 paleoquake (~1500 AD) occurring on the Incline Village fault with nearly of vertical offset.
Some of the highest peaks of the Lake Tahoe Basin that formed during process of Lake Tahoe creation are Freel Peak at , Monument Peak at , Pyramid Peak at (in the Desolation Wilderness), and Mount Tallac at .
Eruptions from the extinct volcano Mount Pluto formed a dam on the north side. Melting snow filled the southern and lowest part of the basin to form the ancestral Lake Tahoe. Rain and runoff added additional water.
Modern Lake Tahoe was shaped and landscaped by scouring glaciers during the Ice Ages, which began a million or more years ago. Lake Tahoe is fed from 63 tributaries with the Truckee River as the only outlet. The Truckee flows northeast through Reno, Nevada and into Pyramid Lake, Nevada which has no outlet.
Soils of the basin come primarily from andesitic volcanic rocks and granodiorite, with minor areas of metamorphic rock. Some of the valley bottoms and lower hill slopes are mantled with glacial moraines, or glacial outwash material derived from the parent rock. Cryopsamments, Cryumbrepts, rockland, rock outcrops and rubble and stony colluvium account for over 70% of the land area in the basin (see USA soil taxonomy). The basin soils (in the < 2 mm fraction) are generally 65-85% sand (0.05–2.0 mm).
Given the great depth of Lake Tahoe, and the locations of the normal faults within the deepest portions of the lake, modeling suggests that earthquakes on these faults can trigger tsunamis. Wave heights of these tsunamis are predicted to be on the order of in height, capable of traversing the lake in just a few minutes. A massive collapse of the western edge of the basin that formed McKinney Bay around 50,000 years ago is thought to have generated tsunami/seiche wave with height approaching .
While Lake Tahoe is a natural lake, it is also used for water storage by the Truckee-Carson Irrigation District (TCID). The lake level is controlled by a dam at the lake's only outlet, the Truckee River, at Tahoe City. The high dam can increase the lake's capacity by .
Climate
Mean annual precipitation ranges from over in watersheds on the west side of the basin to about 26 inches (660 mm) near the lake on the east side of the basin. Most of the precipitation falls as snow between November and April, although rainstorms combined with rapid snow melt account for the largest floods. There is a pronounced annual runoff of snowmelt in late spring and early summer, the timing of which varies from year to year. In some years, summertime monsoon storms from the Great Basin bring intense rainfall, especially to high elevations on the east side of the basin.
August is normally the warmest month at the Tahoe Valley Airport (elevation ) with an average maximum of 78.7 °F (25.9 °C) and an average minimum of 39.8 °F (4.3 °C). January is the coolest month with an average maximum of 41.0 °F (5.0 °C) and an average minimum of 15.1 °F (-9.4 °C). The all-time maximum of 99 °F (37.2 °C) was recorded on July 22, 1988. The all-time minimum of -29 °F (-33.9 °C) was recorded on December 9, 1972, and February 7, 1989. Temperatures exceed 90 °F (32.2 °C) on an average of 2.0 days annually. Minimum temperatures of 32 °F (0 °C) or lower occur on an average of 231.8 days annually, and minimum temperatures of 0 °F (-17.8 °C) or lower occur on an average of 7.6 days annually. Freezing temperatures have occurred every month of the year.
Ecology
Vegetation in the basin is dominated by a mixed conifer forest of Jeffrey pine (Pinus jeffreyi), lodgepole pine (P. contorta), white fir (Abies concolor), and red fir (A. magnifica). The basin also contains significant areas of wet meadows and riparian areas, dry meadows, brush fields (with Arctostaphylos and Ceanothus) and rock outcrop areas, especially at higher elevations. Ceanothus is capable of fixing nitrogen, but mountain alder (Alnus tenuifolia), which grows along many of the basin’s streams, springs and seeps, fixes far greater quantities, and contributes measurably to nitrate-N concentrations in some small streams.
Human history
Native people
The area around Lake Tahoe was originally inhabited by the Washoe tribe of Native Americans. Lake Tahoe was the center and heart of Washoe Indian territory, including the upper valleys of the Walker, Carson, and Truckee Rivers. The English name for Lake Tahoe derives from the Washo dá’aw, "lake".
Exploration
Lt. John C. Frémont was the first non-indigenous person to see Lake Tahoe, during Fremont's second exploratory expedition on February 14. 1844. John Calhoun Johnson, Sierra explorer and founder of "Johnson's Cutoff" (now U.S. Route 50), was the first white man to see Meeks Bay and from a peak above the lake he named Fallen Leaf Lake after his Indian guide. His first job in the west was in the government service, carrying the mail on snowshoes from Placerville to Nevada City, during which time he named the lake "Lake Bigler" in honor of California’s governor John Bigler. In 1853 William Eddy, the surveyor general of California, identified Tahoe as Lake Bigler. In 1862 the U.S. Department of the Interior first introduced the name Tahoe. Both names were used until well into the next century. The lake didn't receive its official and final designation as Lake Tahoe until 1945.
California and Nevada reached the compromise to partition Tahoe between the two when California became a state. With the state line east of the approximate centerline of the lake and then at 39 degrees north latitude, the state border runs southeasterly towards the Colorado River.
Mining era
Upon discovery of gold in the South Fork of the American River in 1848, thousands of gold seekers going west passed near the basin on their way to the gold fields. European civilization first made its mark in the Lake Tahoe basin with the 1858 discovery of the Comstock Lode, a silver deposit just 15 miles (24 km) to the east in Virginia City, Nevada. From 1858 until about 1890, logging in the basin supplied large timbers to shore up the underground workings of the Comstock mines. The logging was so extensive that loggers cut down almost all of the native forest. In 1864, Tahoe City was founded as a resort community for Virginia City, the first recognition of the basin’s potential as a destination resort area.
Development
Public appreciation of the Tahoe basin grew, and during the 1912, 1913, and 1918 congressional sessions, congressmen tried unsuccessfully to designate the basin as a national park. During the first half of the 20th century, development around the lake consisted of a few vacation homes. The post-World War II population and building boom, followed by construction of gambling casinos in the Nevada part of the basin during the mid-1950s, and completion of the interstate highway links for the 1960 Winter Olympics held at Squaw Valley, resulted in a dramatic increase in development within the basin. From 1960 to 1980, the permanent residential population increased from about 10,000 to greater than 50,000, and the summer population grew from about 10,000 to about 90,000. Since the 1980s, development has slowed due to controls on land use.
Government and Politics
Lake Tahoe lies within the borders of both California and Nevada, and as such is not governed by any single entity. In California, Lake Tahoe is divided between Placer County and El Dorado County. In Nevada, Lake Tahoe is divided among Washoe County, Douglas County and Carson City (an independent city).
The Tahoe Regional Planning Agency (TRPA) is a federal regulatory agency which is charged with environmental protection of the Lake Tahoe Basin through land-use regulation and planning.
Mansions
Lake Tahoe is also the location of several 19th and 20th century palatial homes of historical significance. The Thunderbird Lodge built by George Whittel Jr once included nearly 27 miles of the Nevada shoreline. Vikingsholm was the original settlement on Emerald Bay and included an island teahouse and a 28 room home. The Ehrman Mansion is a summer home built by a former Wells Fargo president in Sugar Pine Point and is now a state park.
Environmental issues
Water quality
In spite of land-use planning and export of treated sewage effluent from the basin, the lake is becoming increasingly eutrophic (having an excessive richness of nutrients), with primary productivity increasing by more than 5% annually, and clarity decreasing at an average rate of 0.25 meters per year. Fine sediment, much of it resulting from land disturbance in the basin, accounts for about half of the loss in clarity. Charles Goldman from UC Davis was directly responsible for prompting Tahoe officials to pump all sewage effluent from the basin when Tahoe was being greatly developed in the 1950s. Goldman made local officials understand that even treated sewage would greatly affect the water quality of Lake Tahoe.
Until the early 1980s, nutrient-limitation studies showed that primary productivity in the lake was nitrogen-limited. Now, after a half-century of accelerated nitrogen input (much of it from direct atmospheric deposition), the lake is phosphorus-limited. Because the volume of the lake is so large and its hydraulic residence time so long (about 650 years), its eutrophication may be essentially irreversible.
Lake Tahoe is a tributary watershed drainage element within the Truckee River Basin, and its sole outlet is the Truckee River, which continues on to discharge to Pyramid Lake. Because of the sensitivity of Truckee River water quality (involving two protected species, the cui-ui sucker fish and the Lahontan cutthroat trout), this drainage basin has been studied extensively. The primary investigations were stimulated by the U.S. Environmental Protection Agency, who funded the development of the DSSAM model to analyze water quality below Lake Tahoe.
Lake Tahoe never freezes. Since 1970, it has mixed to a depth of at least a total of 6 or 7 times. Dissolved oxygen is relatively high from top to bottom. Analysis of the temperature records in Lake Tahoe has shown that the lake warmed (between 1969 and 2002) at an average rate of 0.015 °C per year. The warming is caused primarily by increasing air temperatures, and secondarily by increasing downward long-wave radiation. The warming trend is reducing the frequency of deep mixing in the lake, and may have important effects on water clarity and nutrient cycling.
Ecosystem changes
Since the 1960s, the Lake's food web and zooplankton populations have undergone major changes. In 1963–65, opossum shrimp (Mysis relicta) were introduced to enhance the food supply for the introduced Kokanee salmon (Onchorhynchus nerka). The shrimp began feeding on the lake's cladocerans (Daphnia and Bosmina), and their populations virtually disappeared by 1971. The shrimp provide a food resource for salmon and trout, but also compete with juvenile fish for zooplankton. Since the 1970s, the cladoceran populations have somewhat recovered, but not to former levels.
In June 2007, the Angora Fire burned approximately throughout the South Lake Tahoe area. While the impact of ash on the lake's ecosystem is predicted to be minimal, the impact of potential future erosion is not yet known.
Environmental protection
Until recently, construction on the banks of the Lake had been largely under the control of wealthy real estate developers. Construction activities have resulted in a clouding of the lake's blue waters. Currently, the Tahoe Regional Planning Agency is regulating construction along the shoreline (and has won two Federal Supreme Court battles over recent decisions). These regulations are unpopular with many residents, especially those in the Tahoe Lakefront Homeowners Association.
The League to Save Lake Tahoe (Keep Tahoe Blue) has been the public interest watchdog in the Lake Tahoe Basin for 50 years. Founded when a proposal to build a four-lane highway around the lake—with a bridge over the entrance to Emerald Bay—was proposed in 1957, the League has repeatedly thwarted poorly designed development projects and environmentally unsound planning. Currently evaluating the "Pathways 2007" comprehensive plan being developed by TRPA, the League embraces responsible and diversified use of the Lake's resources while protecting and restoring its natural attributes.
Since 1980, the Lake Tahoe Interagency Monitoring Program (LTIMP) has been measuring stream discharge and concentrations of nutrients and sediment in up to 10 tributary streams in the Lake Tahoe Basin, California-Nevada. The objectives of the LTIMP are to acquire and disseminate the water quality information necessary to support science-based environmental planning and decision making in the basin. The LTIMP is a cooperative program with support from 12 federal and state agencies with interests in the Tahoe Basin. This data set, together with more recently acquired data on urban runoff water quality, is being used by the Lahontan Regional Water Quality Control Board to develop a program (mandated by the Clean Water Act) to limit the flux of nutrients and fine sediment to the Lake.
Tourist activities
Much of the area surrounding Lake Tahoe is devoted to the tourism industry and there are many restaurants, ski slopes and casinos catering to visitors.
Winter sports
During ski season, thousands of people from all over Nevada and California, including Las Vegas, Los Angeles, San Diego and San Francisco, flock to the slopes for some of the best skiing in the world. Lake Tahoe, in addition to its panoramic beauty, is well known for its blizzards.
Some of the major ski areas in Tahoe include:
The majority of the ski resorts in the Lake Tahoe region are on the northern end of the lake, near Truckee, California and Reno, Nevada. Kirkwood, Sierra-at-Tahoe and Heavenly are located on the southern side of the lake, approximately 80 miles (129 km) from Reno. It is common for visitors to ski amongst these 3 resorts when staying in Southern Lake Tahoe and not venture to the northern lake resorts (Squaw Valley, Northstar at Tahoe, Sugar Bowl, etc.).
Scattered throughout Tahoe are public and private sled parks. Some, such as Granlibakken are equipped with rope tows to help sledders get up the hill.
Many ski areas around Tahoe also have snow tubing, such as Squaw Valley. Snow tubing is popular among people who are interested in alternative sports. Throughout Tahoe, cross country skiing, snowmobile riding, and snowshoeing are also popular, thus there are many trails for them.
Water sports
During late Spring to early Fall, the lake is popular for water sports and beach activities. The two cities most identified with the Lake Tahoe tourist area are South Lake Tahoe, California and the smaller Stateline; smaller centers on the northern shoreline include Tahoe City and Kings Beach.
Boating is a primary activity in Tahoe in the summer. There are lake front restaurants all over the lake, most equipped with docks and buoys (See the restaurants section). There are all sorts of boating events, such as sailboat racing, firework shows over the lake, guided cruises, and more. As an interstate waterway, Lake Tahoe is subject to the United States Coast Guard. Lake Tahoe is home to Coast Guard Station Lake Tahoe.
SCUBA diving is popular at Lake Tahoe, with some dive sites offering dramatic drop-offs or wall dives. Diving at Lake Tahoe is considered advanced due to the increased risk of decompression sickness (DCS) while diving at such a high altitude.
Hiking and bicycling
There are hundreds of hiking and mountain biking trails all around the lake. They range in length, difficulty, and popularity. One of the most famous of Tahoe's trails is the Tahoe Rim Trail, a 165 mile (270 km) trail that circumnavigates the lake. Directly to the west of the lake is the Granite Chief Wilderness, which provides great hiking and wilderness camping. Also, to the southwest is the very popular Desolation Wilderness. One of the most popular trailheads is the Eagle Lake Trailhead. There are also several paved off-road bicycle paths.
Gambling
Gambling is legal on the Nevada side of Lake Tahoe. Casinos, each with a variety of slot machines and table games, are located on the South Shore in Stateline, and on the North Shore in Crystal Bay and Incline Village.
North Shore - Crystal Bay:
- Cal Neva Lodge & Casino
- Crystal Bay Club
- Jim Kelley's Tahoe Nugget
- Tahoe Biltmore Lodge & Casino
North Shore - Incline Village:
South Shore - Stateline:
Transport
Lake Tahoe is accessible via Reno-Tahoe International Airport or Sacramento International Airport. General aviation access is available via the Lake Tahoe Airport in South Lake Tahoe and the Truckee-Tahoe Airport in Truckee.
The nearest passenger train service is the Amtrak station in Truckee.
Image:Caverock.JPG|Cave Rock Tunnel on US 50
Image:50 through South Lake Tahoe by Mark Miller.jpg|U.S. Route 50 in South Lake Tahoe
Highways
Visitors can reach Lake Tahoe under ideal conditions within 2 hours from the Sacramento area, 1 hour from Reno or 30 minutes from Carson City. In winter months, chains or snow tires are often necessary to reach Tahoe from any direction. Traffic can be heavy on weekends due to tourists if not also from weather.
The primary routes to Lake Tahoe are on Interstate 80 via Truckee, US Highway 50 via South Lake Tahoe and Nevada Highway 431 via Incline Village. All of the highways accessing and encircling Lake Tahoe are paved 2-lane mountain roads. US 50 traverses part of the eastern shore of the lake.
California Highway 89 follows the western shore of the lake through the picturesque wilderness and connects camping, fishing and hiking locations such as those at Emerald Bay State Park, DL Bliss State Park and Camp Richardson. Farther along are communities such as Meeks Bay and Tahoe City. Finally, the highway turns away from the lake and heads northwest toward Truckee.
California Highway 28 completes the circuit from Tahoe City around the northern shore to communities such as Kings Beach, Crystal Bay, and into Incline Village, Nevada where the road becomes Nevada Highway 28. Highway 28 returns along the eastern shore to US Highway 50 near Spooner Lake.
In the media
The Ponderosa Ranch of the TV series Bonanza is located on the Nevada side of Lake Tahoe. The opening sequence of the TV series was filmed at the McFaul Creek Meadow, with Mount Tallac in the background.
In the motion picture The Godfather Part II, the Corleone family lived in a compound on the shores of the Nevada side of Lake Tahoe. In a famous scene from the final minutes of the film, Fredo Corleone is taken out onto the lake for a fishing trip, only to be executed for treachery, on the orders of his brother Michael (Al Pacino), who watches from the shore. The house and grounds portrayed in the film are actually located on the California side of Lake Tahoe: Fleur du Lac, the summer estate of Henry J. Kaiser. The only structures used in the movie that still remain are the complex of old native stone boathouses with their wrought iron gates. Although Fleur du Lac is private property and no one is allowed ashore there, the boathouses and multi-million dollar condominiums are easily viewed from the lake.
Most of the film Smoking Aces was filmed In South Lake Tahoe and Stateline. Many of the hotels and casinos are visible in the film with their older names. The climactic scenes of the 1987 Charles Bronson film Assassination were filmed around and on Lake Tahoe. Both The Bodyguard and City Of Angels filmed their climactic scenes at and around Lake Tahoe and the surrounding Fallen Leaf Lake (California). Meg Ryan's bike-riding scene prominently features Lake Tahoe in the background.
The British TV program Top Gear filmed at Lake Tahoe in Episode 2 of Series 12 in 2008.
Peaks and mountains
See also
External links
- - USGS/Western Geographic Science Center
- - UC Davis research & outreach
- by George Wharton James
- - Lake Tahoe pages
- - California Rivers Assessment database
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