The Mohawk River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map, accessed October 3, 2011 river in the U.S. state of New York. It is the largest tributary of the Hudson River, flowing into it in Cohoes, a few miles north of the state capital of Albany.Mohawk River , The Columbia Gazetteer of North America The river is named for the Mohawk Nation of the Haudenosaunee Confederacy. A significant portion of the river's valley served as the path of the Erie Canal,Mohawk River, Encyclopedia Britannica. A 117-mile (188-km) section of the Canal was dug parallel to the river from Rome to its mouth at Albany. key to developing both New York state and the Great Lakes area. The Mohawk's largest tributary, the Schoharie Creek, accounts for over one quarter (26.83%) of the river's watershed, with West Canada Creek contributing another 16.33% of total.
Course The river's source is at the confluence of the West Branch Mohawk River and East Branch Mohawk River in north-central Oneida County. It begins flowing generally southeastward towards the Hamlet of Hillside, first receiving Blue Brook then McMullen Brook and Haynes Brook. In Hillside is the confluence of Lansing Kill, after which it flows towards the Hamlet of North Western receiving Stringer Brook along the way. After North Western it receives Tannery Brook then Wells Creek in the Hamlet of Frenchville. At Frenchville it curves to the southwest and heads toward the Hamlet of Westernville receiving Deans Gulf along the way. In Westernville it enters Delta Reservoir. After exiting the reservoir it heads south toward the City of Rome receiving Hurlbut Glen Brook and passing the Rome Fish Hatchery along the way. On the south side of the City it enters the Erie Canal and begins to flow east.
After Rome the river flows generally east through the Mohawk Valley, passing by the cities of Utica, Little Falls, Canajoharie, Amsterdam, and Schenectady before entering the Hudson River at Cohoes, just north of Albany.
Modifications The river and its supporting canal, the Erie Canal, connect the Hudson River and port of New York with the Great Lakes at Buffalo, New York."The New York State Canal System" Carmella R. Mantello, In: Proceedings from the 2009 Mohawk Watershed Symposium, Union College, 27 March 2009 The lower part of the Mohawk River has five permanent dams, nine movable dams (seasonal), and five active hydropower plants."Lower Mohawk River Fisheries" Norman McBride, In: Proceedings from the 2009 Mohawk Watershed Symposium, Union College, 27 March 2009
Schoharie Creek and West Canada Creek are the principal tributaries of the Mohawk River. Both of these tributaries have several significant dams including the Hinckley Dam on the West Canada and the Gilboa Dam on the upper reaches of Schoharie Creek. The Gilboa Dam, which was completed in 1926 as part of the New York City water supply system, is the subject of an active and aggressive rehabilitation project."The Gilboa Dam and Schoharie Reservoir" Howard Bartholomew, Michael Quinn, In: Proceedings from the 2009 Mohawk Watershed Symposium, Union College, 27 March 2009
Geology
The Mohawk watershed drains a large section of the Catskill Mountains, the Mohawk Valley proper, and a section of the southern Adirondack Mountains. All three regions have distinct bedrock geology, and the underlying rocks become progressively younger to the south.Rickard, L.V., Y.W. Isachsen, and D.W. Fisher, 1970, Geologic Map of New York State, 1970. 1:250,000. Consists of five sheets: Niagara, Finger Lakes, Hudson-Mohawk, Adirondack, and Lower Hudson, Map and Chart Series No. 15 Overall, this part of New York is represented by lower Paleozoic sedimentary rocks that unconformably overlie the Grenville-aged (Proterozoic, here about 1.1 billion years old) metamorphic rocks of the Adirondacks.Physical Geography of New York In the watershed, these rocks are only significant in the headwaters of the West Canada Creek. Much of the main trunk of the Mohawk River sits in Cambro-Ordovician carbonates (limestone) and Middle Ordovician sandstones and shales.Lower Ordovician Faunas, stratigraphy, and sea-level history of the Middle Beekmantown Group, Northeastern NY, Journal of Paleontology; September 2006; v. 80; no. 5; p. 958-980 The southern tributaries (Catskill Mountains) are underlain by a thin sequence of Devonian limestones that are overlain by a thick sequence of sandstones and shale of the Catskill Delta, which is also Devonian in age.Geologic History of the north-central Appalachians, American Journal of Science, Vol. 297, September 1997, P.729-761
During the Pleistocene (c. 1.8 to 0.01 mya), the watershed was extensively modified by continental glaciation. As a result of glacial scour and deposition, the surficial deposits in much of the watershed are poorly sorted boulder- and clay-rich glacial till. During deglaciation, several glacial lakes left varved clay deposits. In the final stages of deglaciation, approximately 13,350 years ago,Catastrophic draining of Glacial Lake Iroquois, Catastrophic meltwater discharge down the Hudson Valley: A potential trigger for the Intra-Allerød cold period, Geology; February 2005; v. 33; no. 2; p. 89-92 the catastrophic draining of Glacial Lake Iroquois, a pro-glacial lake, was through what would become the modern Mohawk Valley.John C. Ridge, Shed Brook Discontinuity and Little Falls Gravel: Evidence for the Erie interstade in central New York, GSA Bulletin; June 1997; v. 109; no. 6; p. 652-665. In this final phase, the enormous discharge of water caused local deep scour features (e.g. the Potholes at Little Falls), and extensive sand and gravel deposition, which is one of the key sources of municipal groundwater including the Scotia Delta, which is also known as the Great Flats Aquifer."Responsible Planning for future ground water use from the Great Flats Aquifer" Thomas M. Johnson, in: Proceedings from the 2009 Mohawk Watershed Symposium, Union College, 27 March 2009
Etymology The river is named for the Mohawk Nation of the Haudenosaunee Confederacy. In the 1700s and before, the Mohawk people, a section of the Haudenosaunee Confederacy, were based in the Mohawk Valley. Their territory ranged north to the St. Lawrence River, southern Quebec and eastern Ontario; south to greater New Jersey and into Pennsylvania; eastward to the Green Mountains of Vermont; and westward to the border with the Haudenosaunee Oneida Nation's traditional homeland territory.
History The river has long been important to transportation and migration to the west as a passage through the Appalachian Mountains, between the Catskill Mountains and Allegheny Plateau to the south and the Adirondack Mountains to the north. The Mohawk Valley allowed easier passage than going over the mountains to the north or south of the valley. As a result, it was strategically important during the French and Indian War and the American Revolutionary War, and a number of important battles were fought here. The fertile Mohawk Valley also attracted early settlers.
The river was the highway of the native Mohawk people. The Mohawk name for the river is Teionontatátie, "a river flowing through a mountain" (or Yeionontatátie, "going round a mountain").
The first recorded European exploration of the Mohawk was a trip by the Dutchman Harman Meyndertsz van den Bogaert in 1634. He followed the river upstream from Albany for a distance of 100 miles, including all the territory of the Mohawks.
In 1661 Dutch colonists founded the city of Schenectady on the Mohawk River approximately from Albany. "For fifty years Schenectady was the outpost of civilization and Dutch-English rule in the Mohawk valley."
In 1712 the British, now in control of New York, built Fort Hunter at the confluence of the Mohawk and the Schoharie Creek, about upriver from Schenectady. Around 600 Palatine Germans were settled along the Mohawk and Schoharie Creek. Swedish explorer and botanist, Pehr Kalm, visited the area along the river in the mid-18th century where he encountered some of the indigenous peoples belonging to the Haudenosaunee Confederacy, and recorded some of their customs in his journal.
In the early nineteenth century water transport was a vital means of transporting both people and goods. A corporation was formed to build the Erie Canal along the Mohawk River to Lake Erie. Its construction simplified and reduced the difficulties of European westward settler migration and encouraged Manifest Destiny.
Later in the 19th century railroads followed the Water Level Route along the Mohawk Valley, and in the 20th major east–west roads such as Route 5 and a limited-access superhighway, the New York State Thruway (later coterminous with Interstate 90), were built in the valley.
The Mohawk River Heritage Corridor Commission was created to preserve and promote the natural and historic assets of the Mohawk River. This commission was created by the NY State Legislature in 1997 to improve historic preservation along the river.Mohawk Valley Heritage Corridor Commission website
Flooding and discharge The Mohawk River has a relatively long record of flooding that has been documented back to settlement in the 17th century.Historic flooding on the Mohawk River The average volume of water that flows through the Mohawk is about every year.Historic flooding on the Mohawk River Much of the water flows through the watershed in the spring as snow melts rapidly and enters the tributaries and the main trunk of the river. The maximum average daily flow on the river occurs between late March and early April. For the period between 1917 and 2000, the highest mean daily flow is c. as measured at Cohoes, near the confluence with the Hudson. The lowest mean daily flow of occurs in late August. There is a long record of significant and damaging floods along the entire length of the river.
Because the river and its tributaries typically freeze in the winter, the spring melt is commonly accompanied by ice floes that get stuck and jammed along the main trunk of the river. This annual spring breakup typically occurs in the last few weeks of March, although there are numerous floods that have occurred before or after this time, such as in 2018 when the ice jam breakup happened in late February after record warm weather in the region. These ice jams can cause considerable damage to structures along the riverbanks and on the floodplain. The most severe flood of record on the main trunk of the Mohawk River was the spring breakup flood that occurred from 27 to 28 March 1914. This flood caused a tremendous amount of damage to the infrastructure because it was a spring breakup flood with enormous amounts of ice. Ice jams of some significance occur about every other year.Historical and modern ice jams on the Lower Mohawk River - Schenectady"A historical perspective of Ice Jams on the lower Mohawk River." John I. Garver, Jaclyn M.H. Cockburn, In: Proceedings from the 2009 Mohawk Watershed Symposium, Union College, 27 March 2009
One major flood on the Mohawk was on 26–29 June 2006, during the Mid-Atlantic United States flood of 2006. Flooding was caused by a stalled frontal system that resulted in of rain across central New York and widespread flooding occurred in the Mohawk, Delaware, and Susquehanna watersheds. Across the state, this event caused over $227 million in damage and resulted in the loss of four lives. This flooding was acute in the upper parts of the Mohawk watershed."The Flood of June 2006 in the Mohawk, Delaware, and Susquehanna river basins." Thomas P Suro, United States Geological Survey, In: Proceedings from the 2009 Mohawk Watershed Symposium, Union College, 27 March 2009