The Maumee Torrent, also known as the Maumee Megaflood, was a catastrophic draining of Lake Maumee, the ancestor of present-day

Lake Erie Lake Erie ( ) is the fourth-largest lake by surface area of the five Great Lakes in North America and the eleventh-largest globally. It is the southernmost, shallowest, and smallest by volume of the Great Lakes and also has the shortest avera ...

, that occurred approximately 14,000 to 17,000 years ago during the late

Wisconsin glaciation The Wisconsin glaciation, also called the Wisconsin glacial episode, was the most recent glacial period of the North American ice sheet complex, peaking more than 20,000 years ago. This advance included the Cordilleran Ice Sheet, which nucleated ...

. It happened when the waters of Lake Maumee, possibly in response to an advance of the ice front at the eastern end of the lake, overtopped a "

sag SAG, SAg or sag may refer to: Land formations * Sag (geology), or ''trough'', a depressed, persistent, low area * Sag pond, a body of water collected in the lowest parts of a depression People * Ivan Sag (1949–2013), American linguist ...

" or low spot in the Fort Wayne

Moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...

, which was a deposit of glacial debris that acted as a natural dam at the site of present-day

Fort Wayne, Indiana Fort Wayne is a city in Allen County, Indiana, United States, and its county seat. Located in northeastern Indiana, the city is west of the Ohio border and south of the Michigan border. The city's population was 263,886 at the 2020 census ...

. This unleashed a massive flow of water that scoured a one- to two-mile-wide outlet running southwest to the

Wabash River The Wabash River () is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed May 13, 2011 river that drains most of the state of Indiana, and a significant part of Illinois, in the United ...

known as the "Wabash-Erie Channel", which probably followed the course of earlier, less massive drainage. The channel, now a small stream called the

Little River Little River may refer to several places: Australia Streams New South Wales *Little River (Dubbo), source in the Dubbo region, a tributary of the Macquarie River * Little River (Oberon), source in the Oberon Shire, a tributary of Coxs River (Haw ...

, is the largest

topographical Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the landforms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary scienc ...

feature in

Allen County, Indiana Allen County is a county in the U.S. state of Indiana. As of the 2020 Census, the population was 385,410, making it the List of counties in Indiana, third-most populous county in Indiana. The county seat and largest city is Fort Wayne, Indiana, ...

. As much as 30 feet of fine sand, silt and organic sediments were deposited in the channel before drainage reversed and was captured by the present-day

Maumee River The Maumee River (pronounced ) (; ) is a river running in the Midwestern United States from northeastern Indiana into northwestern Ohio and Lake Erie. It is formed at the confluence of the St. Joseph River (Maumee River), St. Joseph and St. Mar ...

U.S. Route 24 U.S. Route 24 or U.S. Highway 24 (US 24) is one of the original United States Numbered Highways of 1926 which runs east and west for most of its routing. It originally ran from Pontiac, Michigan, in the east to Kansas City, Misso ...

between Fort Wayne and Huntington follows the channel.Water Resource Availability in the Maumee River Basin, Indiana, pages 37 & 48
Water Resource Assessment 96-5, Indianapolis: Indiana Department of Natural Resources, Division of Water (1996) Approximately 14,000 years

before present Before Present (BP) or "years before present (YBP)" is a time scale used mainly in archaeology, geology, and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Because ...

, Lake Maumee overtopped the Fort Wayne Moraine. The flood removed all earlier sediment and deepened the valley bottom by . Lake Maumee had reached above

sea level Mean sea level (MSL, often shortened to sea level) is an mean, average surface level of one or more among Earth's coastal Body of water, bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical ...

when the lake poured through a sag in the Fort Wayne Moraine into the ancestral Little River and then the

. There is some evidence that the final rise in lake level that caused it to overtop the moraine was caused by a minor re-advance of the glacier further east in the basin. The soft till of the moraine was quickly eroded by the volume of water in the lake, releasing a massive volume of water. A second outlet opened at Six-Mile Creek into the St. Marys River and into the Little River Valley. The earlier sediments were removed in bulk, leaving only the Sand Point and a few gravel terraces on the valley walls. The flood scoured the length of the Wabash River. The

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

bedrock under the Little River Valley near Huntington created a sill, limiting the depth to which the Torrent and the future river could erode. The well-developed beach ridges in

Ohio Ohio ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the ...

and eastern Allen County show a series of lower lake levels.

References

External links

Indiana Geological Survey: Allen County - A Geologic Atlas

Rich Clark and Scott Russell Sanders, ''Wild and Scenic Indiana'', San Francisco: Brown Trout Publishers, 2005, p. 67.
{{ISBN, 0-7631-8464-0 Geological history of the Great Lakes Floods in the United States Geology of Indiana Geography of Allen County, Indiana Geography of Huntington County, Indiana Megafloods