Triple divide

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A triple divide or triple watershed is a point on Earth's surface where three drainage basins meet. A triple divide results from the intersection of two drainage divides. Triple divides range from prominent mountain peaks to minor side peaks, down to simple slope changes on a ridge which are otherwise unremarkable. The elevation of a triple divide can be thousands of meters to barely above sea level. Triple divides are a common hydrographic feature of any terrain that has rivers, streams and/or lakes.

Map showing worldwide drainage basins and triple divides

Topographic triple divides do not necessarily respect the underground path of water. Thus, depending on the infiltration and the different geological layers, the hydrologic triple divide is often offset from the topographic triple divide.

A hydrological apex is a triple divide whose waters flow into three different oceans. Triple Divide Peak in the U.S. state of Montana and, depending on definition, Snow Dome in Canada are the only such places on Earth.[notes 1]

Africa

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An unnamed hill on the border between the Central African Republic and South Sudan: the exact point is at 09°08′24″N 23°28′07″E / 9.14000°N 23.46861°E / 9.14000; 23.46861 (Congo-Nile-Lake Chad Triple Divide). Water from this point flows to the Atlantic Ocean via the Congo River, to the Mediterranean Sea via the Nile, or to endorheic Lake Chad. At this point meet the second, third and eighth largest drainage basins in the world, making it one of the most important triple divides on earth.[1]

Antarctica

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Antarctica is completely circled by the Southern Ocean, and so it has no triple divides.

Older definitions of the oceans did not include the Southern Ocean, and instead had the Atlantic, Pacific and Indian Oceans touch the shores of Antarctica. Based on this outdated definition, Dome Argus is the highest point in the East Antarctic ice sheet and could be considered a triple divide if it is assumed that the ice forms a watershed. (80°22′S 77°21′E / 80.367°S 77.350°E / -80.367; 77.350 (Dome Argus))[2]

Asia

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Asia is dominated by endorheic basins. There is a point in southern China where the Pacific Ocean, Indian Ocean, and endorheic basins meet and another point in northern China where the Pacific Ocean, endorheic and Arctic Ocean basins meet.[3]

Australia

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Australia has two continental drainage divide tripoints, both close to each other along Queensland's Great Dividing Range. Both are named after two 1845 exploration party leaders who sought to solve the question of Australia's rivers, Thomas Mitchell and Edmund Kennedy.

Europe

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Landmark at Lunghin Pass in Grisons, Switzerland.
Landmark name Coordinates Location Watersheds Divides Refs
Lunghin Pass 46°24′48.71″N 9°39′48.53″E / 46.4135306°N 9.6634806°E / 46.4135306; 9.6634806 (Lunghin Pass) Piz Lunghin, Switzerland
Klepáč 50°09′27.01″N 16°47′27″E / 50.1575028°N 16.79083°E / 50.1575028; 16.79083 (Klepáč) Králický Sněžník Mountains, Czech Republic and Poland [5]
Unnamed point 47°56′29.2″N 5°30′17.2″E / 47.941444°N 5.504778°E / 47.941444; 5.504778 (Langres Plateau Triple Divide) Langres, France
Witenwasserenstock 46°31′41.9″N 8°28′27.3″E / 46.528306°N 8.474250°E / 46.528306; 8.474250 (Witenwasserenstock) Valais and Uri, Switzerland
Roundway Hill 51°22′39.0″N 1°59′08.2″W / 51.377500°N 1.985611°W / 51.377500; -1.985611 (Roundway) Devizes, Wiltshire, United Kingdom [6]

North America

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Triple Divide Peak and Snow Dome are the major triple divides of North America
 
Landmark at the triple divide in Potter County, Pennsylvania.
 
Triple Divide Peak, Montana
 
Snow Dome, British Columbia

North America has 3 triple divides in the United States which are intersections of continental divides, and a fourth one in British Columbia. Waters at these triple divides flow into three different oceans, seas or gulfs. Triple Divide Peak in Montana is considered the triple divide "hydrological apex" of North America, though Snow Dome on the Alberta-British Columbia border also has a claim depending on how the Arctic and Atlantic oceans are defined. North America is the only continent that has a triple point dividing basins draining into three different oceans.[7] Where the Continental Divide splits and joins to form the boundary of the Great Divide Basin, it forms two triple points.

Triple divides of North America
Landmark name Coordinates Location Watersheds Divides Refs
Triple Divide Peak 48°34′23″N 113°31′00″W / 48.57306°N 113.51667°W / 48.57306; -113.51667 (Triple Divide Peak) Flathead County, Montana Continental Divide of the Americas and Laurentian Divide [8]
Snow Dome 52°11′13″N 117°19′01″W / 52.18694°N 117.31694°W / 52.18694; -117.31694 (Snow Dome) Alberta and British Columbia Continental Divide of the Americas and Arctic Divide [9]
Unnamed hill 41°50′48″N 77°50′14″W / 41.8467340°N 77.8372183°W / 41.8467340; -77.8372183 (Unnamed hill in Potter County, PA) Potter County, Pennsylvania Eastern Continental Divide and Saint Lawrence River Divide [10][11]
Hill of Three Waters 47°26.863′N 92°56.8′W / 47.447717°N 92.9467°W / 47.447717; -92.9467 (Hill of Three Waters) approximately 3.2 km (2 mi) north of Hibbing, Minnesota Saint Lawrence River Divide and Laurentian Divide [12]
Eastern divide termination 30°15.146′N 082°23.578′W / 30.252433°N 82.392967°W / 30.252433; -82.392967 (Eastern Continental Divide termination)) near Kissimmee, Florida Lake Okeechobee basin and the Eastern Continental Divide [13]
Great Divide Basin 42°00′01″N 107°59′02″W / 42.00028°N 107.98389°W / 42.00028; -107.98389 (Great Divide Basin North) Wyoming, where the Continental Divide splits and joins to form the boundary of the Great Divide Basin Continental Divide of the Americas, Great Divide Basin [14]
Guzmán Basin 33°08′34″N 107°51′16″W / 33.1427458°N 107.8545162°W / 33.1427458; -107.8545162 (Reeds Peak, NM) Reeds Peak, New Mexico[notes 2] Continental Divide of the Americas, Great Divide Basin [15]
Chihuahua rim, Guzmán Basin 31°19′56.9″N 108°45′21.5″W / 31.332472°N 108.755972°W / 31.332472; -108.755972 (Chihuahua Rim) Chihuahua, Mexico[notes 2]
  • Pacific Ocean (Colorado)
  • Gulf of Mexico (Rio Grande)
  • Guzmán Basin
Continental Divide of the Americas, Great Divide Basin [16]
Three Waters Mountain 43°23′37″N 109°47′09″W / 43.39361°N 109.78583°W / 43.39361; -109.78583 (Three Waters Mountain)[17] Wyoming
  • Gulf of California (Colorado)
  • Pacific Ocean (Columbia)
  • Gulf of Mexico (Mississippi)
Continental Divide of the Americas, Unnamed Divide
Commissary Ridge triple divide 42°35′18″N 110°44′09″W / 42.588347°N 110.735839°W / 42.588347; -110.735839 (Commissary Ridge)[18] Wyoming
  • Gulf of California (Colorado)
  • Pacific Ocean (Columbia)
  • Great Basin

Other points are often considered to be triple divides because they separate basins of continental rivers.

The highest elevation (4,040 m or 13,240 ft) significant triple divide in the lower 48 states of the United States, in Kings Canyon National Park in Fresno/Inyo counties, California, is a sub-peak of Mount Wallace of the central Sierra Nevada:

Numerous other triple divide points result from intersection of river basin divides, including:

South America

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Continental divide of the Americas in South America

There are triple points in South America where the divide splits.

See also

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Notes

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  1. ^ a b c Sources disagree on whether Hudson Bay is part of the Atlantic Ocean or the Arctic Ocean. Snow Dome is a hydrological apex only if Hudson Bay is considered to be part of the Atlantic Ocean, but not if it is considered to be part of the Arctic Ocean.
  2. ^ a b Where the Continental Divide splits in New Mexico and joins in Chihuahua, Mexico, to form the boundary of Guzman Basin are two triple points.

References

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  1. ^ Barbour, K.M. (1961). "A Geographical Analysis of Boundaries in Inter-Tropical Africa". Essays on African Population. Taylor & Francis. GGKEY:W5HTG750C3U. Retrieved 2013-05-04.
  2. ^ "Dome Argus". Peak Bagger. Retrieved December 28, 2021.
  3. ^ "Essentials of Endorheic Basins and Lakes: A Review in the Context of Current and Future Water Resource Management and Mitigation Activities in Central Asia, Figure 1, page 2" (PDF). Journal of Water. Retrieved December 28, 2021.
  4. ^ "Queensland Globe". State of Queensland. Retrieved 9 June 2019.
  5. ^ "Klepáč – Trójmorski Wierch (CZ/PL)". Sharing Water. Retrieved 2023-10-06.
  6. ^ "Catchment Data Explorer". Environment Agency. Retrieved 2024-01-03.
  7. ^ "Ocean Triple Divide Points". Peakbagger.com. Archived from the original on 2017-06-25. Retrieved 2017-07-01.
  8. ^ "Triple Divide Peak". USGS GNIS. Retrieved December 23, 2021.
  9. ^ "Canada National Parks Act (S.C. 2000, c. 32)" (PDF). Schedule 1 - National Parks of Canada. Government of Canada. Retrieved 2021-03-21.
  10. ^ "Triple Continental Divide". Uncovering Pennsylvania. 24 September 2018. Retrieved December 23, 2021.
  11. ^ "Triple Divide". USGS GNIS. Retrieved December 23, 2021.
  12. ^ "Hill of Three Waters or Triple Divide". Historical Markers Database. Retrieved December 22, 2021.
  13. ^ "Cresting the Continental Divide – In Florida?". GeoCaching. Retrieved December 23, 2021.
  14. ^ Francis, Julie. "The Great Divide and Green River Basins". Wyoming State Geological Survey. Retrieved December 30, 2021.
  15. ^ "Reeds Peak". USGS GNIS. Retrieved December 23, 2021.
  16. ^ "List". High Pointers. Retrieved December 23, 2021.
  17. ^ "Three Waters Mountain". Geographic Names Information System. United States Geological Survey, United States Department of the Interior. Retrieved August 25, 2013.
  18. ^ "Commissary Ridge Triple Point". Peak Bagger. Retrieved December 24, 2021.
  19. ^ "Headwaters Hill". USGS.
  20. ^ "Crumbly Spire". Peak Bagger. Retrieved December 24, 2021.

Citations

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  • Joseph A. DiPietro (2012-12-21). Landscape Evolution in the United States: An Introduction to the Geography, Geology, and Natural History. Newnes.