A blackwater river is a type of river with a slow-moving channel flowing through forested swamps or wetlands. As vegetation decays, tannins leach into the water, making a transparent, acidic water that is darkly stained, resembling

black tea Black tea, also translated to red tea in various East Asian languages, is a type of tea that is more oxidized than oolong, yellow, white and green teas. Black tea is generally stronger in flavour than other teas. All five types are made from ...

. Most major blackwater rivers are in the Amazon Basin and the Southern United States. The term is used in fluvial studies, geology, geography, ecology, and biology. Not all dark rivers are blackwater in that technical sense. Some rivers in temperate regions, which drain or flow through areas of dark black loam, are simply black due to the color of the soil; these rivers are ''black mud rivers''. There are also black mud estuaries. Blackwater rivers are lower in nutrients than whitewater rivers and have ionic concentrations higher than rainwater. The unique conditions lead to flora and fauna that differ from both whitewater and clearwater rivers. The classification of Amazonian rivers into black, clear, and whitewater was first proposed by Alfred Russel Wallace in 1853 based on water colour, but the types were more clearly defined by chemistry and physics by from the 1950s to the 1980s. Although many Amazonian rivers fall clearly into one of these categories, others show a mix of characteristics and may vary depending on season and flood levels.

Comparison between white and black waters

Black and white waters differ significantly in their ionic composition, as shown in

Table 1 Table may refer to: * Table (furniture), a piece of furniture with a flat surface and one or more legs * Table (landform), a flat area of land * Table (information), a data arrangement with rows and columns * Table (database), how the table data ...

. Black waters are more acidic, resulting in an

aluminum Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...

concentration greater than that of the more neutral white waters. The major difference is the concentrations of

sodium Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable ...

magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar t ...

, and

potassium Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosph ...

; these are very low in black waters. This has ecological implications. Some animals need more calcium than is available in blackwaters, so for example,

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class G ...

s, which need much calcium to build shells, are not abundant in blackwaters. The lack of dissolved ions in black waters results in a low

conductivity Conductivity may refer to: *Electrical conductivity, a measure of a material's ability to conduct an electric current **Conductivity (electrolytic), the electrical conductivity of an electrolyte in solution ** Ionic conductivity (solid state), ele ...

, similar to that of rainwater. Black and white waters differ in their

plankton Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucia ...

ic fauna and flora. Tables 2 and 3 compare the number of planktonic animals caught in black and white water localities only a few meters apart. The black water was not as extreme an example as the Rio Negro system. However, it can be seen that the black water held greater numbers of rotifers but fewer

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...

s and

mite Mites are small arachnids (eight-legged arthropods). Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari, but genetic analysis does not show clear e ...

s. These crustaceans are important foods for

larval fish Ichthyoplankton (from Greek: ἰχθύς, , "fish"; and πλαγκτός, , "drifter") are the eggs and larvae of fish. They are mostly found in the sunlit zone of the water column, less than 200 metres deep, which is sometimes called the epi ...

. The zones where the two waters mix are attractive to

ostracod Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typi ...

s and young fish. These mixing zones tend to have many animals. The abundance is shown in Table3, which compares animals in of water.

Comparison between clear and black waters

Blackwater rivers resemble clearwater rivers in having a low conductivity and relatively low levels of

dissolved solids In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. If the attractive forces between the solvent ...

, but clearwater rivers have water that often only is somewhat acidic (typical pH ~6.5) and very clear with a greenish color. The main Amazonian clearwater rivers have their source in the

Brazilian Plateau The Brazilian Highlands or Brazilian Plateau ( pt, Planalto Brasileiro) are an extensive geographical region, covering most of the eastern, southern and central portions of Brazil, in all approximately half of the country's land area, or some 4,5 ...

(such as

Tapajós The Tapajós ( pt, Rio Tapajós ) is a river in Brazil. It runs through the Amazon Rainforest and is a major tributary of the Amazon River. When combined with the Juruena River, the Tapajós is approximately long. It is one of the largest clearw ...

Tocantins Tocantins () is one of the 26 states of Brazil. It is the newest state, formed in 1988 and encompassing what had formerly been the northern two-fifths of the state of Goiás. Tocantins covers and had an estimated population of 1,496,880 in 20 ...

, Xingu and some right tributaries of the Madeira), but some originate in the Guiana Shield (such as

Nhamundá Nhamundá is the easternmost municipality in the Brazilian state of Amazonas. Its population was 21,443 (2020) and its area is 14,106 km².IBGE The Brazilian Institute of Geography and Statistics ( pt, Instituto Brasileiro de Geografia e ...

Paru The Border Patrol Police ( th, ตำรวจตระเวนชายแดน); (BPP) is a Thai paramilitary police under the jurisdiction of the Royal Thai Police, responsible for border security and counterinsurgency. History The Thai Bo ...

, and

Araguari Araguari is a municipality in western Minas Gerais state, Brazil. It is in the northern Triângulo Mineiro region, on the Jordão River, a tributary of the Paranaíba River, at an elevation between . The municipality of Araguari has an area of , ...

Blackwater rivers of the world

Amazonia

Apaporis River The Apaporis River is a river of the Vaupés Department, Colombia. It is a tributary of the Caquetá or Japurá River. In the last stretch before the river joins the Caquetá it forms part of the boundary between Colombia and Brazil. See also ...

: a tributary of the Japurá River *

Arapiuns River The Arapiuns River is a river in Pará state in north-central Brazil. It is a tributary of the Tapajós, and merges into the latter river about before Tapajós merges into the Amazon River. Arapiuns is a blackwater river. See also *List of river ...

: a tributary of the Tapajós River * Coari River * Mazaruni River * Mirití-Paraná River * Piorini River * Potaro River: a tributary of the Mazaruni River * Rio Negro: The largest blackwater river in the world; one of the largest Amazonian tributaries. * Tahuayo River *

Tefé River The Tefé River (Teffé River in early accounts; pt, Rio Tefé) is a tributary of the Amazon River ( Solimões section) in Amazonas state in north-western Brazil. The Tefé River flows through the Juruá-Purus moist forests ecoregion. It forms ...

Uatumã River The Uatumã River (sometimes spelled Uatamã) is a river flowing through the state of Amazonas in Brazil. It is a northern tributary of the Amazon River, and known for its extensive peacock bass population. It is a blackwater river. The river f ...

* Urubu River *

Vaupés River Vaupés River (Uaupés River) is a tributary of the Rio Negro in South America. It rises in the Guaviare Department of Colombia, flowing east through Guaviare and Vaupés Departments. It forms part of the international border between the Vaupés ...

Orinoco basin

* Morichal Largo River *

Atabapo River Atabapo River is a river of Venezuela and Colombia. It forms the international boundary between the two countries for much of its length. It is part of the Orinoco River basin. See also *List of rivers of Venezuela This is a list of rivers in Ve ...

: from the Guiana highlands of

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

west into the Orinoco *

Caroní River The Caroní River is the second most important river of Venezuela, the second in flow, and one of the longest, from the Kukenan tepui through to its confluence with the Orinoco River. The name "Caroní" is applied starting from the confluence ...

: from the Guiana Highlands of Venezuela north into the Orinoco. * Caura River: from the Guiana Highlands of Venezuela north into the Orinoco * Inírida River: from Colombia northeast into the

Guaviare River The Guaviare is a tributary of the Orinoco in Colombia. It flows together with the upper Orinoco (until here also called Río Parágua), which it clearly surpasses in length (altogether about 1760 km) and water flow. Thus, the Guaviare is hydrolo ...

which flows into the Orinoco * Ventuari River: from eastern Venezuela southwest into the Orinoco *

Vichada River The Vichada River ( es, Río Vichada, ) is a blackwater river in the country of Colombia, South America. It flows into the Orinoco River. The eastward course of the Vichada is offset by an impact structure An impact structure is a generally ...

: from Colombia east into the Orinoco *

Tomo River Tomo River is a river of Colombia. It is part of the Orinoco River basin. See also *List of rivers of Colombia Atlantic Ocean Amazon River Basin * Amazon River ** Guainía River or Negro River *** Vaupés River or Uaupés River **** Papu ...

: from Colombia east into the Orinoco *

Tuparro River Tuparro River is a river of Colombia found in Vichada Department. It gives its name to El Tuparro National Natural Park. Tuparro is part of the Orinoco River basin. See also *List of rivers of Colombia References

*Rand McNally, The New Inter ...

: from Colombia east into the Orinoco

Southern United States

Ashepoo River Ashepoo River is a short blackwater river in South Carolina, United States. It rises in a confluence of swamps south of Walterboro, flows in a southeast direction and empties into Saint Helena Sound at . The entire course of the river lies withi ...

: along with the Edisto and the

Combahee River The Combahee River ( ) is a short blackwater river in the southern Lowcountry region of South Carolina formed at the confluence of the Salkehatchie and Little Salkehatchie rivers near the Islandton community of Colleton County, South Carolina ...

s in South Carolina makes up the

ACE Basin National Wildlife Refuge The Ernest F. Hollings ACE Basin National Wildlife Refuge is a portion of the larger ACE Basin area, and the only portions that are federally protected. The wildlife refuge is divided into two units: the Edisto River unit and the Combahee Rive ...

. * Big Cypress, Black Cypress, and Little Cypress and the small rivers in the watershed of

Caddo Lake Caddo Lake (french: Lac Caddo) is a lake and bayou (wetland) on the border between Texas and Louisiana, in northern Harrison County and southern Marion County in Texas and western Caddo Parish in Louisiana. The lake is named after the Caddoans ...

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

and

Louisiana Louisiana , group=pronunciation (French: ''La Louisiane'') is a state in the Deep South and South Central regions of the United States. It is the 20th-smallest by area and the 25th most populous of the 50 U.S. states. Louisiana is borde ...

Blackwater River A blackwater river is a type of river with a slow-moving channel flowing through forested swamps or wetlands. As vegetation decays, tannins leach into the water, making a transparent, acidic water that is darkly stained, resembling black tea ...

: a tributary of the

Chowan River The Chowan River (cho-WAHHN)
, from the North Carolina Collection's website at the

: a major river in the western Florida panhandle *

, West Virginia: Located in the

Blackwater Canyon Blackwater Canyon is a rugged, heavily wooded, long gorge carved by the Blackwater River in the Allegheny Mountains of eastern West Virginia, USA. For many years, it has been the object of controversy as environmental activists have contended w ...

in Tucker County. Blackwater Falls, a five-story waterfall, is located along this river with rapids ranging from ClassIII-V+. * Black River: a tributary of the Pee Dee River in

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north ...

and South Carolina *

Cape Fear River The Cape Fear River is a long blackwater river in east central North Carolina. It flows into the Atlantic Ocean near Cape Fear, from which it takes its name. The river is formed at the confluence of the Haw River and the Deep River (North Carol ...

, North Carolina: flows into the Atlantic Ocean. * Cashie River, North Carolina: flows into

Albemarle Sound Albemarle Sound () is a large estuary on the coast of North Carolina in the United States located at the confluence of a group of rivers, including the Chowan and Roanoke. It is separated from the Atlantic Ocean by the Currituck Banks, a bar ...

. *

Caloosahatchee River The Caloosahatchee River is a river on the southwest Gulf Coast of Florida in the United States, approximately long.U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed April 18, 2011 It dr ...

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

: flows west from

Lake Okeechobee Lake Okeechobee (), also known as Florida's Inland Sea, is the largest freshwater lake in the U.S. state of Florida. It is the tenth largest natural freshwater lake among the 50 states of the United States and the second-largest natural freshwa ...

to the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

. *

Chowan River The Chowan River (cho-WAHHN)
, from the North Carolina Collection's website at the

. *

Edisto River The Edisto River is one of the longest free-flowing blackwater rivers in North America, flowing over 250 meandering miles from its sources in Saluda and Edgefield counties, to its Atlantic Ocean mouth at Edisto Beach, South Carolina. It rises i ...

, South Carolina: flows into the Atlantic Ocean. *

Econlockhatchee River The Econlockhatchee River (Econ River for short) is an U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map , accessed April 21, 2011 north-flowing blackwater tributary of the St. Johns River. The E ...

, a

tributary A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drai ...

of the St. Johns River in Central Florida. *

Forked Deer River The Forked Deer River system is the main drainage of the central portion of West Tennessee. Locals pronounce the first word of the river's name with two syllables, as in “Forkéd” (). The Forked Deer consists of various streams designated ...

: located in West Tennessee * Four Hole Swamp, a tributary of the Edisto River in South Carolina. *

Little Manatee River The Little Manatee River flows , from east of Fort Lonesome, Florida South of Hwy 674 and Earl Reynolds Rd In Hillsborough County through southern Hillsborough County, Florida including towns such as Sun City, Florida, and Gulf City, Florida ...

, Florida: flows into

Tampa Bay Tampa Bay is a large natural harbor and shallow estuary connected to the Gulf of Mexico on the west-central coast of Florida, comprising Hillsborough Bay, McKay Bay, Old Tampa Bay, Middle Tampa Bay, and Lower Tampa Bay. The largest freshwater ...

. *

Great Coharie Creek Great Coharie Creek is a long 5th order tributary to the Black River in Sampson County, North Carolina. Variant names According to the Geographic Names Information System, it has also been known historically as: *Cohary Swamp Course Great Co ...

, North Carolina: flows into the Black River. * Little Pee Dee River, South Carolina: flows into the Pee Dee River. *

Lynches River Lynches River, named for Thomas Lynch, Jr., signer of the Declaration of Independence, rises in North Carolina near Waxhaw, North Carolina, at about 700 feet (210 m) elevation, flowing only a short distance to the South Carolina border, and th ...

, South Carolina: flows into the Pee Dee River. *

Lumber Lumber is wood that has been processed into dimensional lumber, including beams and planks or boards, a stage in the process of wood production. Lumber is mainly used for construction framing, as well as finishing (floors, wall panels, wi ...

Drowning Creek The Lumber River, sometimes referred to as the Lumbee River, is a river in south-central North Carolina in the flat Coastal Plain. European settlers first called the river Drowning Creek, which is the name of its headwater. The waterway known as ...

: located in North and South Carolina. Part of

Lumber River State Park Lumber River State Park is a List of North Carolina state parks, North Carolina state park along the Lumber River in Scotland County, North Carolina, Scotland, Hoke County, North Carolina, Hoke, Robeson County, North Carolina, Robeson and Columbu ...

Myakka River (big water) , image = Myakka River.jpg , image_size = , image_caption = Myakka River in El Jobean , image_alt = , map = Myakkarivermap.png , map_size = 200px , map_caption ...

: 66 mile-long river with its headwaters in Manatee County, Florida. The Myakka River discharges into Charlotte Harbor. *

Obion River The Obion River system is the primary surface water drainage system of northwestern Tennessee, United States. Description The Obion has four major forks, the North Fork, Middle Fork, South Fork and Rutherford Fork (which is named after Henr ...

: located in Northwest Tennessee *

Ochlockonee River The Ochlockonee River ( ) is a fast running river, except where it has been dammed to form Lake Talquin in Florida, originating in Georgia and flowing for before terminating in Florida. Background The name is from the Hitchiti language words ...

: a river in northern Florida *

Ogeechee River The Ogeechee River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed April 26, 2011 blackwater river in the U.S. state of Georgia. It heads at the confluence of its North and Sout ...

: a 245-mile river in eastern

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

that passes to the south of the city of Savannah and enters the Atlantic Ocean at Ossabaw Sound. * Ohoopee River: a 119-mile-long (192 km) river in east-central

. It is a tributary of the

Altamaha River The Altamaha River is a major river in the U.S. state of Georgia. It flows generally eastward for 137 miles (220 km) from its origin at the confluence of the Oconee River and Ocmulgee River towards the Atlantic Ocean, where it empt ...

, which flows to the Atlantic Ocean. *

Pasquotank River The Pasquotank River
, from the North Carolina Collection's website at the

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and ...

. Located between Camden and Pasquotank counties, the Pasquotank connects directly to the

and is part of the Intracoastal Waterway via

Elizabeth City Elizabeth City is a city in Pasquotank County, North Carolina, United States. As of the 2020 census, it had a population of 18,629. Elizabeth City is the county seat and largest city of Pasquotank County. It is the cultural, economic and educ ...

. * Peace River: located in central Florida, flows into Charlotte Harbor. *

Pithlachascotee River The Pithlachascotee River, often called the Cotee or "Cootie" River, is a blackwater river in Pasco County, Florida. Originating near Crews Lake, the river flows for over U.S. Geological Survey. National Hydrography Dataset high-resolution flo ...

: a small river in central

* Pocomoke River: a river in southern

Delaware Delaware ( ) is a state in the Mid-Atlantic region of the United States, bordering Maryland to its south and west; Pennsylvania to its north; and New Jersey and the Atlantic Ocean to its east. The state takes its name from the adjacent Del ...

and southeastern

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

on the

Delmarva Peninsula The Delmarva Peninsula, or simply Delmarva, is a large peninsula and proposed state on the East Coast of the United States, occupied by the vast majority of the state of Delaware and parts of the Eastern Shore regions of Maryland and Virginia. ...

. The river is a tributary to the

Chesapeake Bay The Chesapeake Bay ( ) is the largest estuary in the United States. The Bay is located in the Mid-Atlantic region and is primarily separated from the Atlantic Ocean by the Delmarva Peninsula (including the parts: the Eastern Shore of Maryland / ...

. * Santa Fe River: a river in northern Florida *

Satilla River The Satilla River rises in Ben Hill County, Georgia, United States, near the town of Fitzgerald, and flows in a mostly easterly direction to the Atlantic Ocean. Along its approximately U.S. Geological Survey. National Hydrography Dataset hig ...

: a river in southeast

that flows through the city of Waycross and empties into the Atlantic Ocean near

Cumberland Island Cumberland Island, in the southeastern United States, is the largest of the Sea Islands of Georgia. The long-staple Sea Island cotton was first grown here by a local family, the Millers, who helped Eli Whitney develop the cotton gin. With its ...

. * Scuppernong River: a small river in

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

and Tyrrell Counties in eastern

Pettigrew State Park Pettigrew State Park is a North Carolina State Park in Tyrrell and Washington Counties, North Carolina in the United States. It covers around the shore lines of Lake Phelps and the Scuppernong River. The park's developed facilities are sout ...

* Sopchoppy River: a river in northern Florida * St. Mary's River (Florida–Georgia): a 130-mile river located in southeast Georgia and is bordered by the Satilla River Basin to the north and the Suwannee River Basin to the west. * St. Johns River: The largest river in Florida. Flows north through

Jacksonville Jacksonville is a city located on the Atlantic coast of northeast Florida, the most populous city proper in the state and is the List of United States cities by area, largest city by area in the contiguous United States as of 2020. It is the co ...

and into the Atlantic. * St. Sebastian River, Indian River County, Florida. * Suwannee River: a large river in southern

and northern Florida flowing into the Gulf of Mexico *

Upper Little River Upper may refer to: * Shoe upper or ''vamp'', the part of a shoe on the top of the foot * Stimulant, drugs which induce temporary improvements in either mental or physical function or both * ''Upper'', the original film title for the 2013 found fo ...

, North Carolina: flows into the

. * Upper Nanticoke River, Delaware and Maryland: flows into the Chesapeake Bay. * Village Creek, a 63 Mile long stream in the

Big Thicket The Big Thicket is the name given to a somewhat imprecise region of a heavily-forested area of Southeast Texas in the United States. This area represents a portion of the mixed pine-hardwood forests of southeast US. The National Park Service esta ...

region of southeast Texas: flows into the Neches River. * Waccamaw River, North and South Carolina: flows into the Atlantic Ocean. * White Oak River, North Carolina: flows into the Atlantic Ocean. * Wolf River: arises in Northern Mississippi and runs through southwest Tennessee/Memphis into Mississippi River

Northern United States

* Black River, New York: a river starting in the western

Adirondacks The Adirondack Mountains (; a-də-RÄN-dak) form a massif in northeastern New York with boundaries that correspond roughly to those of Adirondack Park. They cover about 5,000 square miles (13,000 km2). The mountains form a roughly circular d ...

that flows into

Lake Ontario Lake Ontario is one of the five Great Lakes of North America. It is bounded on the north, west, and southwest by the Canadian province of Ontario, and on the south and east by the U.S. state of New York. The Canada–United States border ...

. *

Black River (Gogebic County) The Black River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed May 1, 2012 river on the Upper Peninsula of the U.S. state of Michigan, flowing mostly in Gogebic County into Lake ...

Michigan Michigan () is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the List of U.S. states and ...

: a river in the far western

Upper Peninsula The Upper Peninsula of Michigan – also known as Upper Michigan or colloquially the U.P. – is the northern and more elevated of the two major landmasses that make up the U.S. state of Michigan; it is separated from the Lower Peninsula by ...

that flows into

Lake Superior Lake Superior in central North America is the largest freshwater lake in the world by surface areaThe Caspian Sea is the largest lake, but is saline, not freshwater. and the third-largest by volume, holding 10% of the world's surface fresh wa ...

. The northern section of the river is listed as a

National Wild and Scenic River The National Wild and Scenic Rivers System was created by the Wild and Scenic Rivers Act of 1968 (Public Law 90-542), enacted by the U.S. Congress to preserve certain rivers with outstanding natural, cultural, and recreational values in a free- ...

. *

Mullica River The Mullica River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed April 1, 2011 river in southern New Jersey in the United States. The Mullica was once known as the ''Little Egg Ha ...

and its tributaries from the

Pine Barrens Pine barrens, pine plains, sand plains, or pineland areas occur throughout the U.S. from Florida to Maine (see Atlantic coastal pine barrens) as well as the Midwest, West, and Canada and parts of Eurasia. Perhaps the most well known pine-barre ...

New Jersey New Jersey is a state in the Mid-Atlantic and Northeastern regions of the United States. It is bordered on the north and east by the state of New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delaware ...

, where the dark water is called cedar water * Gooseberry River: a river in northern Minnesota that leaches from peat bogs and pine forests * Ocqueoc River, Michigan: a river in the northern Lower Peninsula that flows in Lake Huron *

Tahquamenon River The Tahquamenon River is an U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed January 3, 2012 blackwater river in the U.S. state of Michigan that flows in a generally eastward direction th ...

: a river in the

that flows into

* Tuckahoe River,

: a short river in southern New Jersey that flows into Great Egg Harbor

Africa

* Most Congo and Lower Guinean rivers that flow through rainforests are blackwater. * The Congo basin lakes Mai-Ndombe and Tumba are blackwater. * The

New Calabar The Kalabari Kingdom, also called Elem Kalabari ( Kalabari: ''New Shipping Port''), is the independent traditional state of the Kalabari people, an Ijaw ethnic group, in the Niger River Delta. It is recognized as a traditional state in what is n ...

and Sombreiro Rivers (both exiting in the Niger River Delta) are blackwater.

Australia

Gordon River The Gordon River is a major perennial river located in the central highlands, south-west, and western regions of Tasmania, Australia. Course and features The Gordon River rises below Mount Hobhouse in the Franklin-Gordon Wild Rivers Nationa ...

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

: a river rising in the center of the island and flowing westward, emptying into

Macquarie Harbour Macquarie Harbour is a shallow fjord in the West Coast region of Tasmania, Australia. It is approximately , and has an average depth of , with deeper places up to . It is navigable by shallow-draft vessels. The main channel is kept clear by th ...

on the West Coast * Pieman River, Tasmania: a river on the West Coast which leaches from rainforests and heathlands *

Davey River The Davey River is a perennial river located in the south-west region of Tasmania, Australia. Course and features The Davey River rises on the western slopes of the Frankland Range, below Coronation Peak, and flows generally south by west thro ...

, Tasmania: a relatively small river in the southwest corner of the island which runs through extensive heathlands, peat bogs and button grass plains * Noosa River,

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , establishe ...

: a small section of the Noosa River running between Lake Cootharaba and Lake Cooroibah Other rivers in Australia may experience infrequent 'blackwater events' associated with flood waters connecting to forested floodplains and these events may be associated with hypoxic waters ow oxygen Examples include the

Murray River The Murray River (in South Australia: River Murray) (Ngarrindjeri: ''Millewa'', Yorta Yorta: ''Tongala'') is a river in Southeastern Australia. It is Australia's longest river at extent. Its tributaries include five of the next six longest ...

Edward River Edward River, or Kyalite River, an anabranch of the Murray River and part of the Murray–Darling basin, is located in the western Riverina region of south western New South Wales, Australia. The river rises at Picnic Point east of Mathoura, a ...

Wakool River Wakool River, an anabranch of the Edward River that is part of the Murray River catchment within the Murray–Darling basin, is located in the western Riverina region of south western New South Wales, Australia. The Wakool River splits from t ...

and

Murrumbidgee River The Murrumbidgee River () is a major tributary of the Murray River within the Murray–Darling basin and the second longest river in Australia. It flows through the Australian state of New South Wales and the Australian Capital Territory, desce ...

Indonesia

* Sabangau River

Images of blackwater rivers

Amazon blackwater.JPG, Amazon tributary classified as blackwater Bald Cypress.JPG, Cluster of

bald cypress ''Taxodium distichum'' (bald cypress, swamp cypress; french: cyprès chauve; ''cipre'' in Louisiana) is a deciduous conifer in the family Cupressaceae. It is native to the southeastern United States. Hardy and tough, this tree adapts to a wide ...

trees in

Trap Pond State Park Trap Pond State Park is a 3,653 acre (8.5 km²) Delaware state park located near Laurel, Delaware, USA. It is one of the largest surviving fragments of what was once an extensive wetland in what is now southwestern Sussex County. The state ...

in Southern

Manaus-Amazon-NASA.jpg, Manaus, the largest city on the Amazon River, from a

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...

satellite image, surrounded by the muddy Amazon river and the blackwater Rio Negro File:Blackwater and muddy water, Big Thicket NP. Jack Gore Baygall Unit, Hardin Co. TX; 3 Apr 2020.jpg, A cypress slough where baygall blackwater (left) mixes with the more typical muddy waters (right) of the region.

National Preserve, Jack Gore Baygall Unit, Hardin Co. Texas; 3 April 2020 File:Caño Ceima Cachivera, Mitú, Vaupés.jpg, Caño Ceima Cachivera, Mitú, Vaupés: one of the most visited waterfalls and indigenous communities In

Mitú Mitú () is the capital town of the department of Vaupés in Colombia. It is a small town located in South eastern Colombia in the Amazon Basin. Founded in 1936, Mitú lies next to the Vaupés River at 180 meters above sea level. It is where th ...

, Colombia

References

{{Wetlands Aquatic ecology Rivers