Badwater Basin is an endorheic basin in Death Valley National Park, Death Valley, Inyo County, California, noted as the lowest point in North America, with an elevation of 282Â ft (86Â m) below sea level. Mount Whitney, the highest point in the contiguous 48 United States, is only 84.6 miles (136Â km) to the north west.
The site itself consists of a small spring-fed pool of "bad water" next to the road in a sink; the accumulated salts of the surrounding basin make it undrinkable, thus giving it the name. The pool does have animal and plant life, including pickleweed, aquatic insects, and the Badwater snail.
Adjacent to the pool, where water is not always present at the surface, repeated freezeâ€"thaw and evaporation cycles gradually push the thin salt crust into hexagonal honeycomb shapes.
The pool is not the lowest point of the basin: the lowest point (which is only slightly lower) is several miles to the west and varies in position, depending on rainfall and evaporation patterns. The salt flats are hazardous to traverse (in many cases being only a thin white crust over mud), and so the sign marking the low point is at the pool instead. The basin was considered the lowest elevation in the Western Hemisphere until the discovery of Laguna del Carbón in Argentina at âˆ'344 ft (âˆ'105 m).
Geography
At Badwater Basin, significant rainstorms flood the valley bottom periodically, covering the salt pan with a thin sheet of standing water. Newly formed lakes do not last long though, because the 1.9Â in (48Â mm) of average rainfall is overwhelmed by a 150Â in (3,800Â mm) annual evaporation rate. This is the greatest evaporation potential in the United States, meaning that a 12Â ft (3.7Â m) lake could dry up in a single year. When the basin is flooded, some of the salt is dissolved; it is redeposited as clean crystals when the water evaporates.
A popular site for tourists is the sign marking "sea level" on the cliff above the Badwater Basin.
History
It is theorized that during the Holocene, when the regional climate was less dry, streams running from nearby mountains gradually filled Death Valley to a depth of almost 3 ft (1 m), and together with Cotton Bail Marsh and Middle Basin, made up the 80 mi (130 km) long, Lake Manly. Some of the minerals left behind by earlier Death Valley lakes dissolved in the shallow water, creating a briny solution. The wet times did not last as the climate warmed and rainfall declined. The lake began to dry up and minerals dissolved in the lake became increasingly concentrated as water evaporated. Eventually, only a briny soup remained, forming salty pools on the lowest parts of Death Valley's floor. Salts (95% table salt â€" NaCl) began to crystallize, coating the surface with a thick crust from 3 to 60 in (8 to 152 cm).
See also
- Death Valley pupfish
- List of elevation extremes by country
References
Further reading
- John McKinney: California's Desert Parks: A Day Hiker's Guide. Wilderness Press 2006, ISBN 0-89997-389-2, S. 54â€"55
- Don J. Easterbrook (Hrsg): Quaternary Geology of the United States. Geological Society of America 2003, ISBN 94-592-0504-6, S.63â€"64
External links
- Badwater Basin in the Encyclopædia Britannica
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