View source for Lake Lahontan

{{Short description|Former lake in Nevada, United States}}
{{For|the modern reservoir|Lake Lahontan (reservoir)}}
{{Use American English|date=July 2025}}
{{Infobox body of water
| name               = Lake Lahontan
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| image              = 
| caption            = 
| image_bathymetry   = Wpdms shdrlfi020l lake lahontan b.jpg
| caption_bathymetry = Extent of prehistoric Lake Lahontan
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| location           = Northwestern [[Nevada]], parts of northeastern California and southern Oregon
| coordinates        = {{Coord|39.8|-118.5|region:US-NV_type:waterbody_dim:350km|display=inline,title}}
| type               = [[Endorheic lakes|Endorheic]] prehistoric lake
| etymology          = [[Louis-Armand de Lom d'Arce de Lahontan, Baron de Lahontan]]
| part_of            = [[Great Basin]]
| basin_countries    = United States
| date-flooded       = {{approx}} 12,700 years ago
| area               = {{convert|8500|sqmi}}
| max-depth          = {{convert|500 to 900|ft}}
| elevation          = {{convert|4157|ft}}
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| pushpin_map             = USA Nevada#United States
| mapframe       = yes
}}

'''Lake Lahontan''' was a large [[endorheic basin|endorheic]] [[list of prehistoric lakes|prehistoric lake]] during the [[Pleistocene]] that occupied modern northwestern [[Nevada]] and extended into northeastern [[California]] and southern [[Oregon]]. The area of the former lake is a large portion of the [[Great Basin]] that borders the [[Sacramento River]] watershed to the west.

The lake was named by [[Clarence King]] during the [[Geological Exploration of the Fortieth Parallel]]. The name honors [[Louis-Armand de Lom d'Arce de Lahontan, Baron de Lahontan]], a French soldier and explorer.<ref>{{cite book | url=http://dwgateway.library.unr.edu/keck/histtopoNV/Origin_of_Place_Names_Files/1941NevadaOriginofNames-pt1.pdf | title=Origin of Place Names: Nevada | publisher=W.P.A. | author=Federal Writers' Project | year=1941 | pages=11}}</ref><ref>{{cite report |title=Report of the geological exploration of the fortieth parallel |first=Clarence |last=King |year=1870 |number=18 |page=13 |url=https://archive.org/details/reportofgeologic01unit/mode/2up?q=lahontan |access-date=April 21, 2022}}</ref>

==History==
[[File:Lake bonneville map.svg|thumb|Lake Lahontan and other Late Pleistocene paleolakes in the Great Basin (such as Lake Bonneville) during the last major global glaciation. Lake Lahontan is shown in the context of western North America and the southern margins of the Laurentide and Cordilleran ice sheets.]]
At its peak approximately 12,700 years ago (during a period known as the Sehoo Highstand), the lake had a surface area of over {{convert|8500|sqmi}},<ref>{{cite web |url=http://www.rangerovers.net/expeditions/lahontan.html |title=Lake Lahontan Expedition |publisher=RangeRovers.net |access-date=2013-07-13 |archive-url=https://web.archive.org/web/20130712031911/http://www.rangerovers.net/expeditions/lahontan.html |archive-date=2013-07-12 |url-status=dead }}</ref> with its largest component centered at the location of the present [[Carson Sink]]. Near present day [[Pyramid Lake (Nevada)|Pyramid Lake]] the depth of the lake was then about {{convert|900|ft}}<ref>{{cite web |url=http://www.walkerlakenv.org/history.htm |publisher=Walker Lake Interpretive Association |title=History |access-date=2013-07-13}}</ref> and {{convert|500|ft}} at what is present day [[Black Rock Desert]]. Lake Lahontan, during this [[Last glacial period|most recent glacial period]], would have been one of the largest lakes in [[North America]].<ref>{{cite web |url=http://parks.nv.gov/parks/lahontan-state-recreation-area/ |title=Lahontan State Recreation Area |publisher=Nevada State Parks |access-date=2013-07-13}}</ref>

Climate change around the end of the Pleistocene [[epoch (geology)|epoch]] led to a gradual [[desiccation]] of ancient Lake Lahontan. The lake had largely disappeared in its extended form by about 9,000 years ago. As the surface elevation dropped, the lake broke up into series of smaller lakes, most of which rapidly dried up, leaving only a [[Dry lake|playa]]. These playas include the [[Black Rock Desert]], the [[Carson Sink]], and the [[Humboldt Sink]]. The only modern remnants existing as true lakes are [[Pyramid Lake (Nevada)|Pyramid Lake]] and [[Walker Lake (Nevada)|Walker Lake]]. [[Winnemucca Lake]] has been dry since the 1930s and [[Honey Lake]] periodically desiccates.  The ancient shoreline is evidenced by [[tufa]] formations throughout the area.

Surprisingly, the watershed feeding Lake Lahontan is not thought to have been significantly wetter during its highstand than it is currently. Rather, its desiccation is thought to be mostly due to increase in the [[evaporation]] rate as the climate warmed.{{Citation needed|date=May 2008}} Recent computer simulations (using the [[DSSAM Model]] and other techniques) indicate,<ref>C.M.Hogan, Marc Papineau et al. ''Development of a dynamic water quality simulation model for the Truckee River'', Earth Metrics Inc., Environmental Protection Agency Technology Series, Washington D.C. (1987)</ref> if precipitation and evaporation rates within the watershed were maintained at their historical yearly maximum and minimum, respectively, and if diversions of the [[Truckee River]] ceased, the [[Last Glacial Period#North America|Ice Age]] extent of Lake Lahontan might return.

Archaeological evidence along the shore indicates the existence of the lake coincided roughly with the first appearance of humans in the region. The [[Lahontan cutthroat trout]] evolved as a predator species within the waters of Lake Lahontan, feeding on native [[Tui chub|chub]] and [[Catostomidae|sucker]]. This subspecies of [[cutthroat trout]] survives today in tributary rivers of the [[Great Basin]], and has been reintroduced to Pyramid Lake and Walker Lake after being [[Local extinction|extirpated]] during the 20th century.

==See also==
* [[Lahontan Valley]]
* [[Lake Modoc]]
* [[Pluvial lake]]
* [[Lake Bonneville]]
* [[Lake Corcoran]]

==References==
{{Reflist}}

{{Pleistocene Lakes and Seas}}

{{DEFAULTSORT:Lahonton, Lake}}
[[Category:Former lakes of the United States]]
[[Category:Glacial lakes of the United States]]
[[Category:Lakes of the Great Basin]]
[[Category:Geology of California]]
[[Category:Geology of Nevada]]
[[Category:Geology of Oregon]]
[[Category:Pleistocene United States]]