California 10/2008 Ricky - Lake Tahoe

We take a break from our reading, resting, restoring, and recreating to take the short drive down to Lake Tahoe.

Lake Tahoe is the second deepest lake in the United States, with a maximum depth of 1,645 feet trailing only Oregon's Crater Lake at 1,949 ft. Tahoe is also the 16th deepest lake in the world, and the fifth deepest in average depth. It is about 22 mi long and 12 mi wide and has 72 mi of shoreline and a surface area of 191 square miles.

Approximately two-thirds of the shoreline is in California. The south shore is dominated by the lake's largest city, South Lake Tahoe, CA, which adjoins the town of Stateline, NV, while Tahoe City, CA 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 US Forest Service.

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 created the Lake Tahoe Basin in between.

More technically, Lake Tahoe is the youngest of several extensional basins. The Lake Tahoe basin is formed by a series of large down-to-the-east normal faults.

Some of the highest peaks of the Lake Tahoe Basin that formed during process of Lake Tahoe creation are Free Peak at 10,891 feet, Monument Peak at 10,067 feet, Pyramid Peak at 9,983 feet , and Mount Tallac at 9,735 feet.

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, NV and into Pyramid Lake, Nevada which has no outlet.

Soils of the basin come primarily from volcanic rocks. Some of the valley bottoms and lower hill slopes are mantled with glacial moraines, or glacial outwash material derived from the parent rock.

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 10 to 33 ft 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 330 ft.

While Lake Tahoe is a natural lake, it is also used for water storage. The lake level is controlled by a dam at the lake's only outlet, the Truckee River, at Tahoe City. The 6 feet high dam can increase the lake's capacity by 732,000 acre·ft.

Native people

The area around Lake Tahoe was originally inhabited by the Washoe tribe. Lake Tahoe was the center and heart of Washoe Indian territory. The English name for Lake Tahoe derives from the Washo dá’aw, "lake".

Exploration

Lt. John C. Fremont 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 US 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, during which time he named the lake "Lake Bigler" in honor of California’s governor. In 1853 William Eddy, the surveyor general of California, identified Tahoe as Lake Bigler. In 1862 the US 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 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 to the east in Virginia City, NV. 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.

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.

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 156 km³ (37 cu mi) and its hydraulic residence time so long (about 650 years), its eutrophication may be essentially irreversible.

Lake Tahoe is a tributary watershed drainage element, 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), this drainage basin has been studied extensively.

Lake Tahoe never freezes. Since 1970, it has mixed to a depth of at least 1,300 ft 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.

We stop to take in a local Oktoberfest.

Oktoberfest is a sixteen-day festival held each year in Munich, Bavaria, Germany during late September (and running to early October). It is one of the most famous events in the city and the world's largest fair, with some six million people attending every year, and is an enjoyable event with an important part of Bavarian culture. Other cities across the world also hold Oktoberfest celebrations, modeled after the Munich event.

Oktoberfestbiers are the beers that have been served at the event in Munich since 1818, and are supplied by 6 breweries known as the Big Six. Traditionally Oktoberfestbiers were the lagers of around 5.5 to 6% - brewed in March and allowed to ferment slowly during the summer months. Originally these would have been dark lagers, but from 1872 a strong March brewed version of an amber-red made by Josef Sedlmayr became the favourite Oktoberfestbier.

How about a little Oooomppaaah music.

Since the 1970s the type of beer served at the festival has been a pale lager between 5 and 6% abv, and the terms Oktoberfest and Märzen are used by non-Oktoberfest brewers in Germany and the USA to market pale lagers of this strength.

The Munich Oktoberfest, traditionally, takes place during the sixteen days up to and including the first Sunday in October. In 1990, the schedule was modified in response to German reunification so that if the first Sunday in October falls on the 1st or 2nd, then the festival will go on until October 3 (German Unity Day).

Visitors also eat huge amounts of food, most of it traditional hearty fare such as chicken, roast pork, knuckle of pork, grilled fish on a stick, sausages, and pretzels, as well as all those krauts.

Emerald Bay is a state park and a National Natural Landmark. The park is home to Eagle Falls and Vikingsholm, a 38-room mansion that is one of the finest examples of Scandinavian architecture in the western hemisphere. The park contains the only island in Lake Tahoe, Fannette Island.

In 1969, Emerald Bay was recognized as a National Natural Landmark. In 1994, California State Parks included the surrounding water of the bay as a part of the park, making Emerald Bay one of the first underwater parks of its type in the state, protecting the various wrecks and other items on the bay's bottom.

Summer temperatures at the park range from the low 40 °F (4 °C) at night to mid-70 °F (25 °C) during the day, and during the winter visitors will usually experience temperatures between 20 and 40 °F (-7 and 4 °C). During harsh winters, the bay freezes over. The bay is about 1.7 miles (2.7 km) in length, and about two-thirds of a mile (1 km) wide at its widest point.

We complete the circle of the Lake, stop to do a little shopping, and head back to Sierraville.