Lake Tahoe

Coordinates: 39°N 120°W / 39°N 120°W / 39; -120
Source: Wikipedia, the free encyclopedia.

Lake Tahoe
Dáʔaw (
Carson City (6%)
Average depth1,000 ft (300 m)[1]
Max. depth1,645 ft (501 m)
Water volume36 cu mi (150 km3; 120,000,000 acre⋅ft)[2]
Residence time650 years
Shore length171 mi (114 km)
Surface elevation6,225 ft (1,897 m)[1]
FrozenRarely, in Emerald Bay[3]
IslandsFannette Island
SettlementsIncline Village, NV
South Lake Tahoe, CA
Stateline, NV
Tahoe City, CA
Kings Beach, CA
1 Shore length is not a well-defined measure.

Lake Tahoe (/ˈtɑːh/; Washo: Dáʔaw) is a freshwater lake in the Sierra Nevada of the Western United States, straddling the border between California and Nevada. Lying at 6,225 ft (1,897 m) above sea level, Lake Tahoe is the largest alpine lake in North America,[4] and at 122,160,280 acre⋅ft (150.7 km3) it trails only the five Great Lakes as the largest by volume in the United States. Its depth is 1,645 ft (501 m), making it the second deepest in the United States after Crater Lake in Oregon (1,949 ft or 594 m).[1]

The lake was formed about two million years ago as part of the Lake Tahoe Basin, and its modern extent was shaped during the ice ages. It is known for the clarity of its water and the panorama of surrounding mountains on all sides.[5] The area surrounding the lake is also referred to as Lake Tahoe, or simply Tahoe; its English name is derived from its Washo name, Dáʔaw.[6] More than 75% of the lake's watershed is national forest land, covered by the Lake Tahoe Basin Management Unit of the United States Forest Service.

Lake Tahoe is a major tourist attraction in both Nevada and California. It is home to winter sports, summer outdoor recreation, and scenery enjoyed throughout the year. Snow and ski resorts are a significant part of the area's economy and reputation.[7][8] The Nevada side also offers several lakeside casino resorts, with highways providing year-round access to the entire area.

Toponym

The name for Lake Tahoe derives from the

Washo word for the lake, Dáʔaw, meaning 'the lake.'[9] Even though dáʔaw is used in the names of other lakes with modifiers (for example, Á’waku dáʔaw for Pyramid Lake, meaning 'trout lake'), it often is used without a modifier to refer to Lake Tahoe. This may be because of Tahoe's importance to Washo culture.[10]

Geography

Lake Tahoe is the second deepest lake in the U.S., with a maximum depth of 1,645 feet (501 m),[1][11] trailing Oregon's Crater Lake at 1,949 ft (594 m).[11] Tahoe is the 17th[12] deepest lake in the world, and the sixth deepest in average depth. It is about 22 mi (35 km) long and 12 mi (19 km) wide and has 72 mi (116 km) of shoreline and a surface area of 191 square miles (490 km2). The lake is so large that its surface is noticeably convex due to the curvature of the Earth.[13] At lake level the opposing shorelines are below the horizon at its widest parts; by nearly 100 feet (30 m) at its maximum width, and by some 320 feet (98 m) along its length.[14][15] Visibility may vary somewhat with atmospheric refraction;[16] when the air temperature is much greater than the lake temperature, looming may occur where the lake surface or opposing shoreline is lifted above the horizon. Fata Morgana may be responsible for Tahoe Tessie sightings.

North Lake Tahoe aerial photo

Approximately two-thirds of the shoreline is in California.

USGS Huc 18100200) of 505 sq mi (1,310 km2) is the land area that drains to the lake and the Lake Tahoe drainage divide traverses the same general area as the Tahoe Rim Trail
.

Lake Tahoe, view of California shore from Nevada side

Lake Tahoe is fed by 63 tributaries. These drain an area about the same size as the lake and produce half its water, the other half by direct precipitation.

Sunrise over lake Tahoe
Panorama of Emerald Bay (California) October 2023

The Truckee River is the lake's only outlet,[4] flowing northeast through Reno, Nevada, into Pyramid Lake which has no outlet. It accounts for one third of the water that leaves the lake, the rest evaporating from the lake's surface. Evaporation is thought to account for 40 to 60 percent of the water usage.[18] The flow of the Truckee River and the height of the lake are controlled by the Lake Tahoe Dam at the outlet. The natural rim is at 6,223 ft (1,897 m) above sea level. The maximum legal limit to which the lake can be allowed to rise in order to store water is at 6,229.1 ft (1,898.6 m); a spillway at the dam controls overflow.[19] Around New Year 1996/1997 a Pineapple Express atmospheric river melted snow and caused the lake and river to overflow, inundating Reno and surrounding areas.[20]

Natural history

Geology

The Lake Tahoe Basin was formed by vertical motion (normal)

grabens) created the Lake Tahoe Basin in between.[1] This kind of faulting is characteristic of the geology of the adjoining Great Basin
to the east.

Lake Tahoe is the youngest of several extensional basins of the

Tunnel Creek Road, Lake Tahoe, Nevada (2022)

Three principal faults form the Lake Tahoe basin: the West Tahoe Fault, aligned between

recurrence interval of 3,000–4,000 years.[26]

Some of the highest peaks of the Lake Tahoe Basin that formed during the process of Lake Tahoe creation are Freel Peak at 10,891 feet (3,320 m), Monument Peak at 10,067 feet (3,068 m), Pyramid Peak at 9,984 feet (3,043 m) (in the Desolation Wilderness), and Mount Tallac at 9,735 feet (2,967 m).[1] The north shore boasts three peaks at over 10,000 feet (3,048 m): Mount Rose at 10,785 feet (3,287 m), Mount Houghton at 10,490 feet (3,197 m) and Relay Peak at 10,388 feet (3,166 m). Mt. Rose is a very popular hiking and backcountry skiing destination.

Eruptions from the now-extinct volcano Mount Pluto formed a volcanic 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.[27]

The Sierra Nevada adjacent to Lake Tahoe were carved by scouring

Fallen Leaf Lake, among others. Lake Tahoe itself never held glaciers, but instead water is retained by damming Miocene
volcanic deposits.

Soils of the basin come primarily from

glacial outwash material derived from the parent rock. Sandy soils, rock outcrops and rubble and stony colluvium
account for over 70% of the land area in the basin. 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 in 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 (3 to 10 m) in height, capable of traversing the lake in just a few minutes.[28] A massive collapse of the western edge of the basin that formed McKinney Bay around 50,000 years ago is thought to have generated a tsunami/seiche wave with a height approaching 330 ft (100 m).[29]

Climate

Fallen Leaf Lake and Lake Tahoe in background from Angora Ridge Rd. to the Angora Lakes
Resort

Lake Tahoe has a

monsoon
storms from the Great Basin bring intense rainfall, especially to high elevations on the northeast side of the basin.

August is normally the warmest month at the Lake Tahoe Airport (elevation 6,254 ft; 1,906 m) 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 °C) was recorded on July 22, 1988. The all-time minimum of −16 °F (−27 °C) was recorded on December 9, 1972. Temperatures exceed 90 °F (32 °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 (−18 °C) or lower occur on an average of 7.6 days annually. Freezing temperatures have occurred in every month of the year.[30][31]

Climate data for Tahoe City, California (Elevation 6,230 ft; 1,900 m)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °F (°C) 59
(15)
60
(16)
67
(19)
74
(23)
89
(32)
90
(32)
99
(37)
94
(34)
87
(31)
80
(27)
70
(21)
60
(16)
99
(37)
Mean daily maximum °F (°C) 38.6
(3.7)
40.3
(4.6)
44.0
(6.7)
50.4
(10.2)
59.6
(15.3)
68.7
(20.4)
77.9
(25.5)
77.2
(25.1)
69.8
(21.0)
58.8
(14.9)
46.9
(8.3)
40.3
(4.6)
56.0
(13.3)
Mean daily minimum °F (°C) 19.1
(−7.2)
19.9
(−6.7)
22.8
(−5.1)
26.9
(−2.8)
32.8
(0.4)
38.6
(3.7)
44.4
(6.9)
43.7
(6.5)
39.0
(3.9)
32.3
(0.2)
25.8
(−3.4)
20.8
(−6.2)
30.5
(−0.8)
Record low °F (°C) −14
(−26)
−15
(−26)
−6
(−21)
5
(−15)
9
(−13)
24
(−4)
22
(−6)
28
(−2)
21
(−6)
9
(−13)
1
(−17)
−16
(−27)
−16
(−27)
Average precipitation inches (mm) 5.97
(152)
5.29
(134)
4.12
(105)
2.14
(54)
1.20
(30)
0.65
(17)
0.26
(6.6)
0.30
(7.6)
0.59
(15)
1.82
(46)
3.57
(91)
5.55
(141)
31.47
(799)
Average snowfall inches (cm) 45.9
(117)
36.5
(93)
35.2
(89)
15.9
(40)
3.7
(9.4)
0.2
(0.51)
0
(0)
0
(0)
0.3
(0.76)
2.4
(6.1)
15.5
(39)
35.2
(89)
190.7
(484)
Source: The Western Regional Climate Center[32]

Ecology