The Traverse Gap is an ancient river channel on the border of the U.S. states of Minnesota and South Dakota between Lake Traverse and Big Stone Lake at Browns Valley, Minnesota. It has an unusual distinction for a valley: it contains a continental divide, and in some floods water has flowed across that divide from one drainage basin to the other. Federal courts Supreme Court Chief Justice Associate Justices Elections Presidential elections Midterm elections Political Parties Democratic Republican Third parties State & Local government Governors Legislatures (List) State Courts Counties/Parishes/Boroughs, Cities, and Towns Other countries Politics Portal      A U.S. state is any one of the fifty subnational entities of... Capital Saint Paul Largest city Minneapolis Area  Ranked 12th  - Total 87,014 sq mi (225,365 km²)  - Width 250 miles (400 km)  - Length 400 miles (645 km)  - % water 8. ... Official language(s) English Capital Pierre Largest city Sioux Falls Area  Ranked 17th  - Total 77,163 sq mi (199,905 km²)  - Width 210 miles (340 km)  - Length 380 miles (610 km)  - % water 1. ... Lake Traverse is the southernmost body of water in the Hudson Bay watershed of North America. ... Big Stone Lake is a long, narrow freshwater lake and reservoir forming the border between western Minnesota and northeastern South Dakota. ... Browns Valley is a city located in Traverse County, Minnesota. ... Fljótsdalur in East Iceland, a rather flat valley A valley or a low area between two hills dale (in Scotland, a glen) is a landform, which can range from a few square kilometres to hundreds or even thousands of square kilometres in area. ... A continental divide is a line of elevated terrain which forms a border between two watersheds such that water falling on one side of the line eventually travels to one ocean or body of water, and water on the other side travels to another, generally on the opposite side of... A flood (in Old English flod, a word common to Teutonic languages; compare German Flut, Dutch vloed from the same root as is seen in flow, float) is an overflow of water, an expanse of water submerging land, a deluge. ... This article includes a list of works cited or a list of external links, but its sources remain unclear because it lacks in-text citations. ...

Geological history

The gap was cut at the end of the last ice age. At the end of the Wisconsonian glaciation, Glacial Lake Agassiz formed from the meltwater of the Laurentide Ice Sheet. Outlets to the north were blocked by the glacier, and the outlet to the south was dammed by the Big Stone Moraine which had been left by earlier glaciers. Lake Agassiz filled until it overtopped the moraine about 12,000 years ago. The resulting enormous outflow of the lake carved a natural spillway through the moraine, through which ran Glacial River Warren.^[1] Beyond the gap, River Warren coursed down the present-day Minnesota River valley; it flowed for about 3,000 years until the ice sheet melted sufficiently to allow Lake Agassiz another outlet.^[2] With its source now draining elsewhere, River Warren ceased to flow, and the spillway gorge became the Traverse Gap.^[3] Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years For the animated movie, see Ice Age (movie). ... This article or section should be merged with Wisconsin glaciation The Wisconsinian was the last major advance of continental glaciers in North America. ... Lake Agassiz was an immense lake—bigger than all of the present-day Great Lakes combined—in the center of North America, which was fed by glacial runoff at the end of the last ice age. ... The Laurentide ice sheet was a massive sheet of ice that covered hundreds of thousands of square miles, including most of Canada and a large portion of the northern United States, between ~ 90,000 and ~ 18,000 years before the present day. ... Moraine at Mono Lake, California, United States Moraines clearly seen on a side glacier of the Gorner Glacier, Zermatt, Switzerland. ... Spillway of Llyn Brianne dam in Wales A Spillway is a structure used to provide for the controlled release of flood flows from a dam or levee into a downstream area, typically being the river that has been dammed. ... Glacial River Warren or River Warren is the name of a prehistoric river which drained Lake Agassiz in central North America between 11,700 and 9,400 years ago. ... The Mendota Bridge crossing the Minnesota River, just above its mouth View of the Minnesota River from Memorial Park; southeast of Granite Falls, MN. The Minnesota River is a tributary of the Mississippi River, approximately 332 miles (534 km) long, in the state of Minnesota in the United States. ... [[ == Headline text == This article does not cite its references or sources. ...

Topography and hydrology

Traverse Gap from ice-covered Lake Traverse (bottom of frame) south to Big Stone Lake (top). Interbasin flooding is shown: The Little Minnesota River, which originates in the Mississippi watershed, is flooding the Traverse Gap; floodwaters are crossing the continental divide into Lake Traverse in the watershed of Hudson Bay (lower right).

Despite the low elevation and flat topography of its floor, the Traverse Gap marks the Northern Divide between the watersheds of the Arctic and the Atlantic Oceans. On the north, Lake Traverse is the source of the Bois des Sioux River, a source stream of the Red River of the North, which drains via Lake Winnipeg and the Nelson River to Hudson Bay in the Arctic Ocean. To the south, Big Stone Lake is the source of River Warren's remnant, the Minnesota River, tributary to the Mississippi, which drains to the Gulf of Mexico and the Atlantic. Big Stone Lake is now fed by the Little Minnesota River, the headwaters of which are in South Dakota, enters the gap from the west, and flows south through the old channel to Big Stone Lake. Within the gap, the Little Minnesota (part of the Mississippi watershed) is less than one mile (1.6 km) from Lake Traverse (in the drainage basin of Hudson Bay).^[3][4] Continental divides in North America. ... Watershed has more than one meaning: Look up watershed in Wiktionary, the free dictionary. ... The Arctic Ocean, located in the northern hemisphere and mostly in the Arctic north polar region, is the smallest of the worlds five oceans and the shallowest. ... See also the Red River disambiguation page. ... Winnipeg Beach, Manitoba, on Lake Winnipeg Lake Winnipeg (52°30′N 97°47′W) is a very large (24,400 km²) lake in central North America, in the province of Manitoba, Canada, about 55 km north of the city of Winnipeg. ... The Nelson River is a river of north-central North America, in the Canadian province of Manitoba. ... Hudson Bay, Canada. ... The Mississippi River, derived from the old Ojibwe word misi-ziibi meaning great river (gichi-ziibi big river at its headwaters), is the second-longest named river in North America, with a length of 2320 miles (3733 km) from Lake Itasca to the Gulf of Mexico. ... Gulf of Mexico in 3D perspective. ... “Atlantic” redirects here. ... The Little Minnesota River is a tributary of the Minnesota River in northeastern South Dakota and west-central Minnesota in the United States. ...

The floor of the Traverse Gap is flat, which allows the waters of one basin to flood across the continental divide into the other basin in times of high water. The maximum elevation on the floor of the valley is 987 feet (300.8 m) above sea level.^[3] The Browns Valley Dike at the south end of Lake Traverse is at the same elevation; this structure was built to reduce the likihood of flooding south across the continental divide. At 983.9 feet (299.9 m),^[5][6] that divide is lower than the level of the dike, and flooding at Lake Traverse has the potential to drain over the Big Stone Dike into the Minnesota River watershed. At the south end of the gap, the Big Stone Lake reservoir pool is maintained at 967 feet (294.7 m), and it has recently flooded to over 975 feet (297.2 m). The Little Minnesota River upstream and at a higher elevation near the divide has flooded to a level where it drained across that divide into Lake Traverse.^[5] While the natural state of the area has been altered by the dike and control structures on the two lakes, interbasin flooding did occur prior to construction of those improvements.^[5] The Traverse Gap therefore allows waters which would naturally flow to the Atlantic Ocean to flow to the Arctic instead,^[7] and in the past has allowed water from Lake Traverse to flow in the other direction to Big Stone Lake in the Atlantic basin.^[8]

Geography and human uses

The ancient channel through the gap is a mile (1.6 km) wide and some 130 feet (40 m) deeper than the surrounding terrain through which it was carved.^[3] The distance from Lake Traverse to Big Stone Lake is about five miles (8 km). The Minnesota-South Dakota border longitudinally bisects the old channel; the continental divide crosses it transversely at its northern end.^[9]

Historically the Traverse Gap was used by the Red River ox carts as one of the earliest of the Red River Trails; it now is crossed by Minnesota State Highway 28. The community of Browns Valley, Minnesota is in the northern part of the gap. The rural part of the valley floor contains pastures, cropland, and marshes along the Little Minnesota River. The Red River ox cart was a large, two-wheeled cart made entirely of wood, and usually in the form of oak and pulled by oxen. ... The Red River Trails were a network of ox trails connecting the Red River Colony (Selkirk Settlement) in the Canadian province of Manitoba, with the head of navigation of the Mississippi River at St. ... Minnesota State Highway 28 is a highway which runs from the South Dakota border in Browns Valley, Minnesota to Little Falls, Minnesota. ... Browns Valley is a city located in Traverse County, Minnesota. ...

References

2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini era. ... May 5 is the 125th day of the year in the Gregorian calendar (126th in leap years). ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini era. ... May 4 is the 124th day of the year in the Gregorian calendar (125th in leap years). ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini era. ... May 4 is the 124th day of the year in the Gregorian calendar (125th in leap years). ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini era. ... May 6 is the 126th day of the year in the Gregorian calendar (127th in leap years). ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini era. ... May 4 is the 124th day of the year in the Gregorian calendar (125th in leap years). ...

External links to visual media

• Browns Valley, MN Spring 2007. Flooding. JOR Engineering, Inc. (2007-03-14). Retrieved on 2007-05-10. Additional photographs of March 2007 flooding of Traverse Gap, including interbasin flooding across the continental divide.
• "Geology of the Southern Outlet of Glacial Lake Agassiz - Field Trip". Minnesota Groundwater Association Newsletter 23 (4): 15. Retrieved on 2007-05-04.  Photograph across Traverse Gap, showing flat valley floor and adjacent terraced uplands.

Coordinates: 45°35′6″N, 96°49′48″W 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini era. ... May 10 is the 130th day of the year in the Gregorian calendar (131st in leap years). ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini era. ... May 4 is the 124th day of the year in the Gregorian calendar (125th in leap years). ... This page is a candidate for speedy deletion. ... Map of Earth showing lines of latitude (horizontally) and longitude (vertically), Eckert VI projection; large version (pdf, 1. ...