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The Amazon River (dark blue) and the rivers which flow into it (medium blue). Amazonrivermap.svg
The Amazon River (dark blue) and the rivers which flow into it (medium blue).
The start of a mountain stream. ReichenbachBegin2.jpg
The start of a mountain stream.

A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to using names such as creek, brook, rivulet, and rill. There are no official definitions for the generic term river as applied to geographic features, [1] although in some countries or communities a stream is defined by its size. Many names for small rivers are specific to geographic location; examples are "run" in some parts of the United States, "burn" in Scotland and northeast England, and "beck" in northern England. Sometimes a river is defined as being larger than a creek, [2] but not always: the language is vague. [1]


Melting toe of Athabasca Glacier, Jasper National Park, Alberta, Canada Melting Toe of Athabasca Glacier.jpg
Melting toe of Athabasca Glacier, Jasper National Park, Alberta, Canada

Rivers are part of the water cycle. Water generally collects in a river from precipitation through a drainage basin from surface runoff and other sources such as groundwater recharge, springs, and the release of stored water in natural ice and snowpacks.

Rivers are often considered major features within a landscape; however, they actually only cover around 0.1% of the land on Earth. They are made more obvious and significant to humans since many human cities and civilizations are built around the freshwater supplied by rivers and streams. [3] Most of the major cities of the world are situated on the banks of rivers, as they are, or were, used as a source of water, for obtaining food, for transport, as borders, as a defensive measure, as a source of hydropower to drive machinery, for bathing, and as a means of disposing of waste. In the pre-industrial era, larger rivers were a major obstruction to the movement of people, goods, and armies across them. Towns often developed at the few locations they could be crossed. Many major cities such as London are located at the lowest point at which a river could be bridged. [4]

Potamology is the scientific study of rivers, while limnology is the study of inland waters in general.


The Colorado River at Horseshoe Bend, Arizona Horseshoe Bend TC 27-09-2012 15-34-14.jpg
The Colorado River at Horseshoe Bend, Arizona
The Porvoo River (Porvoonjoki) in the medieval town of Porvoo, Finland Porvoon uusisilta 1.JPG
The Porvoo River (Porvoonjoki) in the medieval town of Porvoo, Finland

Source and drainage basin

A river begins at a source (or more often several sources) which is usually a watershed, drains all the streams in its drainage basin, follows a watercourse, and ends either at a mouth or mouths which could be a confluence, river delta, etc. The water in a river is usually confined to a channel, made up of a stream bed between banks. In larger rivers there is often also a wider floodplain shaped by flood-waters over-topping the channel. Floodplains may be very wide in relation to the size of the river channel. This distinction between river channel and floodplain can be blurred, especially in urban areas where the floodplain of a river channel can become greatly developed by housing and industry.

The term upriver (or upstream) refers to the direction towards the source of the river, i.e. against the direction of flow. Likewise, the term downriver (or downstream) describes the direction towards the mouth of the river, in which the current flows. The term left bank refers to the left bank in the direction of flow, right bank to the right in the direction of flow.


Rivers can flow down mountains, through valleys or along plains, and can create canyons or gorges. The river channel typically contains a single stream, but some rivers flow as several interconnecting streams, producing a braided river. [5] Braided rivers occur on peneplains and some of the larger river deltas. Anastamosing rivers are similar to braided rivers and are quite rare; they have multiple sinuous channel - 1 carrying large volumes of sediment. There are rare cases of river bifurcation in which a river divides, and the resultant flows end in different seas. An example is the Nerodime River in Kosovo.

A river flowing in its channel is a source of energy that acts on the river channel to change its shape and form. In 1757, German hydrologist Albert Brahms empirically observed that the submerged weight of objects that may be carried away by a river is proportional to the sixth power of the river flow speed. [6] This formulation is also sometimes called Airy's law. [7] Thus, if the speed of flow is doubled, the flow would dislodge objects with 64 times as much submerged weight. In mountainous torrential zones, this can be seen as erosion channels through hard rocks and the creation of sands and gravels from the destruction of larger rocks. A river valley that was created from a U-shaped glaciated valley can often easily be identified by the V-shaped channel that it has carved.

In the middle reaches where a river flows over flatter land, meanders may form through erosion of the river banks and deposition on the inside of bends. Sometimes the river will cut off a loop, shortening the channel and forming an oxbow lake or billabong. Rivers that carry large amounts of sediment may develop conspicuous deltas at their mouths. Rivers whose mouths are in saline tidal waters may form estuaries.

Throughout the course of the river, the total volume of water transported downstream will often be a combination of the free water flow together with a substantial volume flowing through sub-surface rocks and gravels that underlie the river and its floodplain (called the hyporheic zone). For many rivers in large valleys, this unseen component of flow may greatly exceed the visible flow.

Types and ratings

Nile River delta, as seen from Earth orbit. The Nile is an example of a wave-dominated delta that has the classic Greek letter delta (D) shape after which river deltas were named. NileDelta-EO.JPG
Nile River delta, as seen from Earth orbit. The Nile is an example of a wave-dominated delta that has the classic Greek letter delta (Δ) shape after which river deltas were named.
A radar image of a 400-kilometre (250 mi) river of methane and ethane near the north pole of Saturn's moon Titan PIA16197 Titan river.jpg
A radar image of a 400-kilometre (250 mi) river of methane and ethane near the north pole of Saturn's moon Titan

Rivers have been classified by many criteria including their topography, their biotic status, and their relevance to white water rafting or canoeing activities.

Subsurface rivers: subterranean and subglacial

Most but not all rivers flow on the surface. Subterranean rivers flow underground in caves. Such rivers are frequently found in regions with limestone geologic formations. Subglacial streams are the braided rivers that flow at the beds of glaciers and ice sheets, permitting meltwater to be discharged at the front of the glacier. Because of the gradient in pressure from the overlying weight of the glacier, such streams can even flow uphill.

Permanence of flow: perennial and ephemeral

An intermittent river (or ephemeral river) only flows occasionally and can be dry for several years at a time. These rivers are found in regions with limited or highly variable rainfall, or can occur because of geologic conditions such as a highly permeable river bed. Some ephemeral rivers flow during the summer months but not in the winter. Such rivers are typically fed from chalk aquifers which recharge from winter rainfall. In England these rivers are called bournes and give their name to places such as Bournemouth and Eastbourne. Even in humid regions, the location where flow begins in the smallest tributary streams generally moves upstream in response to precipitation and downstream in its absence or when active summer vegetation diverts water for evapotranspiration. Normally dry rivers in arid zones are often identified as arroyos or other regional names.

The meltwater from large hailstorms can create a slurry of water, hail and sand or soil, forming temporary rivers. [8]

Stream order classification

The Strahler Stream Order ranks rivers based on the connectivity and hierarchy of contributing tributaries. Headwaters are first order while the Amazon River is twelfth order. Approximately 80% of the rivers in the world are of the first and second order.

The ways in which a river's characteristics vary between its upper and lower course are summarized by the Bradshaw model. Power-law relationships between channel slope, depth, and width are given as a function of discharge by "river regime".

In certain languages, distinctions are made among rivers based on their stream order. In French, for example, rivers that run to the sea are called fleuve, while other rivers are called rivière. For example, in Canada, the Churchill River in Manitoba is called la rivière Churchill as it runs to Hudson Bay, but the Churchill River in Labrador is called le fleuve Churchill as it runs to the Atlantic Ocean. As most rivers in France are known by their names only without the word rivière or fleuve (e.g. la Seine , not le fleuve Seine, even though the Seine is classed as a fleuve), one of the most prominent rivers in the Francophone commonly known as fleuve is le fleuve Saint-Laurent (the St. Lawrence River). Since many fleuves are large and prominent, receiving many tributaries, the word is sometimes used to refer to certain large rivers that flow into other fleuves; however, even small streams that run to the sea are called fleuve (e.g. fleuve côtier , "coastal fleuve").

Topographical classification

Rivers can generally be classified as either alluvial, bedrock, or some mix of the two. Alluvial rivers have channels and floodplains that are self-formed in unconsolidated or weakly consolidated sediments. They erode their banks and deposit material on bars and their floodplains.

Bedrock rivers form when the river downcuts through the modern sediments and into the underlying bedrock. This occurs in regions that have experienced some kind of uplift (thereby steepening river gradients) or in which a particularly hard lithology causes a river to have a steepened reach that has not been covered in modern alluvium. Bedrock rivers very often contain alluvium on their beds; this material is important in eroding and sculpting the channel. Rivers that go through patches of bedrock and patches of deep alluvial cover are classified as mixed bedrock-alluvial.

Alluvial rivers can be further classified by their channel pattern as meandering, braided, wandering, anastomose, or straight. The morphology of an alluvial river reach is controlled by a combination of sediment supply, substrate composition, discharge, vegetation, and bed aggradation.

Biotic classification

There are several systems of classification based on ecological conditions typically assigning classes from the most oligotrophic or unpolluted through to the most eutrophic or polluted. [9] Other systems are based on a whole eco-system approach such as developed by the New Zealand Ministry for the Environment. [10] In Europe, the requirements of the Water Framework Directive has led to the development of a wide range of classification methods including classifications based on fishery status [11]

A system of river zonation used in francophone communities [12] [13] divides rivers into three primary zones:

The international scale of river difficulty is used to rate the challenges of navigation—particularly those with rapids. Class I is the easiest and Class VI is the hardest.


Studying the flows of rivers is one aspect of hydrology. [14]



River meandering course RiverMeanderingCourse.jpg
River meandering course

Rivers flow downhill with their power derived from gravity. The direction can involve all directions of the compass and can be a complex meandering path. [15] [16] [17]

Rivers flowing downhill, from river source to river mouth, do not necessarily take the shortest path. For alluvial streams, straight and braided rivers have very low sinuosity and flow directly down hill, while meandering rivers flow from side to side across a valley. Bedrock rivers typically flow in either a fractal pattern, or a pattern that is determined by weaknesses in the bedrock, such as faults, fractures, or more erodible layers.


Volumetric flow rate, also known as discharge, volume flow rate, and rate of water flow, is the volume of water which passes through a given cross-section of the river channel per unit time. It is typically measured in cubic metres per second (cumec) or cubic feet per second (cfs).

Volumetric flow rate can be thought of as the mean velocity of the flow through a given cross-section, times that cross-sectional area. Mean velocity can be approximated through the use of the law of the wall. In general, velocity increases with the depth (or hydraulic radius) and slope of the river channel, while the cross-sectional area scales with the depth and the width: the double-counting of depth shows the importance of this variable in determining the discharge through the channel.


Fluvial erosion

In its youthful stage, a river causes erosion in the watercourse, deepening the valley. Hydraulic action loosens and dislodges aggregate which further erodes the banks and the river bed. Over time, this deepens the river bed and creates steeper sides which are then weathered. The steepened nature of the banks causes the sides of the valley to move downslope causing the valley to become V-shaped.

Waterfalls also form in the youthful river valley where a band of hard rock overlays a layer of soft rock. Differential erosion occurs as the river erodes the soft rock more readily than the hard rock, this leaves the hard rock more elevated and stands out from the river below. A plunge pool forms at the bottom and deepens as a result of hydraulic action and abrasion. [18]


Flash flooding caused by a large amount of rain falling in a short amount of time Trapped woman on a car roof during flash flooding in Toowoomba 2.jpg
Flash flooding caused by a large amount of rain falling in a short amount of time
The mouth of the River Seaton in Cornwall after heavy rain caused flooding and significant erosion of the beach. Seaton Beach after heavy rainfall.jpg
The mouth of the River Seaton in Cornwall after heavy rain caused flooding and significant erosion of the beach.

Flooding is a natural part of a river's cycle. The majority of the erosion of river channels and the erosion and deposition on the associated floodplains occur during the flood stage. In many developed areas, human activity has changed the form of river channels, altering magnitudes and frequencies of flooding. Some examples of this are the building of levees, the straightening of channels, and the draining of natural wetlands.

In many cases human activities in rivers and floodplains have dramatically increased the risk of flooding. Straightening rivers allows water to flow more rapidly downstream, increasing the risk of flooding places further downstream. Building on flood plains removes flood storage, which again exacerbates downstream flooding. The building of levees only protects the area behind the levees and not those further downstream. Levees and flood-banks can also increase flooding upstream because of the back-water pressure as the river flow is impeded by the narrow channel banks. Detention basins finally also reduce the risk of flooding significantly by being able to take up some of the flood water.

Sediment yield

Sediment yield is the total quantity of particulate matter (suspended or bedload) reaching the outlet of a drainage basin over a fixed time frame. Yield is usually expressed as kilograms per square kilometre per year. Sediment delivery processes are affected by a myriad of factors such as drainage area size, basin slope, climate, sediment type (lithology), vegetation cover, and human land use / management practices.

The theoretical concept of the 'sediment delivery ratio' (ratio between yield and total amount of sediment eroded) indicates that not all of the sediment is eroded within a certain catchment that reaches out to the outlet (e.g., deposition on floodplains). Such storage opportunities are typically increased in catchments of larger size, thus leading to a lower yield and sediment delivery ratio.

Frozen river in Alaska Frozen river in Alaska.jpg
Frozen river in Alaska

Brackish water

Brackish water occurs in most rivers where they meet the sea. The extent of brackish water may extend a significant distance upstream, especially in areas with high tidal ranges.


River biota

The organisms in the riparian zone respond to changes in river channel location and patterns of flow. The ecosystem of rivers is generally described by the river continuum concept, which has some additions and refinements to allow for dams and waterfalls and temporary extensive flooding. The concept describes the river as a system in which the physical parameters, the availability of food particles and the composition of the ecosystem are continuously changing along its length. The food (energy) that remains from the upstream part is used downstream.

The general pattern is that the first order streams contain particulate matter (decaying leaves from the surrounding forests) which is processed there by shredders like Plecoptera larvae. The products of these shredders are used by collectors, such as Hydropsychidae, and further downstream algae that create the primary production become the main food source of the organisms. All changes are gradual and the distribution of each species can be described as a normal curve, with the highest density where the conditions are optimal. In rivers succession is virtually absent and the composition of the ecosystem stays fixed.


The chemistry of rivers is complex and depends on inputs from the atmosphere, the geology through which it travels and the inputs from man's activities. The chemical composition of the water has a large impact on the ecology of that water for both plants and animals and it also affects the uses that may be made of the river water. Understanding and characterizing river water chemistry requires a well designed and managed sampling and analysis.


Leisure activities on the River Avon at Avon Valley Country Park, Keynsham, United Kingdom. A boat giving trips to the public passes a moored private boat. River avon at keynsham arp.jpg
Leisure activities on the River Avon at Avon Valley Country Park, Keynsham, United Kingdom. A boat giving trips to the public passes a moored private boat.

Construction material

The coarse sediments, gravel, and sand, generated and moved by rivers are extensively used in construction. In parts of the world this can generate extensive new lake habitats as gravel pits fill with water. In other circumstances it can destabilize the river bed, and the course of the river and cause severe damage to spawning fish populations which rely on stable gravel formations for egg laying. In upland rivers, rapids with whitewater or even waterfalls occur. Rapids are often used for recreation, such as whitewater kayaking. [19]

Energy production

Watermill in Belgium. Braine-le-Chateau JPG02.jpg
Watermill in Belgium.

Fast flowing rivers and waterfalls are widely used as sources of energy, via watermills and hydroelectric plants. Evidence of watermills shows them in use for many hundreds of years, for instance in Orkney at Dounby Click Mill. Prior to the invention of steam power, watermills for grinding cereals and for processing wool and other textiles were common across Europe. In the 1890s the first machines to generate power from river water were established at places such as Cragside in Northumberland and in recent decades there has been a significant increase in the development of large scale power generation from water, especially in wet mountainous regions such as Norway.

Food source

Rivers have been a source of food since pre-history. [20] They are often a rich source of fish and other edible aquatic life and are a major source of fresh water, which can be used for drinking and irrigation. Rivers help to determine the urban form of cities and neighborhoods, and their corridors often present opportunities for urban renewal through the development of foreshoreways such as river walks. Rivers also provide an easy means of disposing of wastewater and, in much of the less developed world, other wastes.

Rivers have been used for navigation for thousands of years. The earliest evidence of navigation is found in the Indus Valley civilization, which existed in northwestern India around 3300 BC. [21] Riverine navigation provides a cheap means of transport and is still used extensively on most major rivers of the world like the Amazon, the Ganges, the Nile, the Mississippi, and the Indus.

In some heavily forested regions such as Scandinavia and Canada, lumberjacks use rivers to float felled trees downstream to lumber camps for further processing, saving much effort and cost by transporting the huge heavy logs by natural means. [22]

Political borders

Rivers have been important in determining political boundaries and defending countries. For example, the Danube was a long-standing border of the Roman Empire, and today it forms most of the border between Bulgaria and Romania. The Mississippi in North America and the Rhine in Europe are major east–west boundaries in those continents. The Orange and Limpopo Rivers in southern Africa form the boundaries between provinces and countries along their routes.

Sacred rivers

Sacred rivers and their reverence is a phenomenon found in several religions, especially religions in which nature is revered. For example, the Indian-origin religions of Buddhism, Hinduism, Jainism, and Sikhism revere and preserve groves, forests, trees, mountains and rivers as sacred. Among the most sacred rivers in Hinduism are the Ganges, [23] Yamuna, [24] [25] and Sarasvati [26] rivers. Other sacred rivers for Indian religions include the Rigvedic rivers, the Narmada, the Godavari, and the Kaveri rivers. The Vedas and Gita, the most sacred of Hindu texts, were written on the banks of the Sarasvati river.


River bank repair River bank repair on the River Avon, Saltford.jpg
River bank repair

Rivers are often managed or controlled to make them more useful or less disruptive to human activity.

River management is a continuous activity as rivers tend to 'undo' the modifications made by people. Dredged channels silt up, sluice mechanisms deteriorate with age, levees and dams may suffer seepage or catastrophic failure. The benefits sought through managing rivers may often be offset by the social and economic costs of mitigating the bad effects of such management. As an example, in parts of the developed world, rivers have been confined within channels to free up flat flood-plain land for development. Floods can inundate such development at high financial cost and often with loss of life.

Rivers are increasingly managed for habitat conservation, as they are critical for many aquatic and riparian plants, resident and migratory fishes, waterfowl, birds of prey, migrating birds, and many mammals.


Man-made causes, such as the over-exploitation and pollution, are the biggest threats and concerns which are making rivers ecologically dead and drying up the rivers.

Plastic pollution imposes threats on aquatic life and river ecosystems because of plastic's durability in the natural environment. Plastic debris may result in entanglement and ingestion by aquatic life such as turtles, birds, and fish, causing severe injury and death. Human livelihoods around rivers are also impacted by plastic pollution through direct damage to shipping and transport vessels, effects on tourism or real estate value, and the clogging of drains and other hydraulic infrastructure leading to increased flood risk. [27]

See also

Arts, entertainment, and media

Related Research Articles

Levee Ridge or wall to hold back water

A levee, dike, dyke, embankment, floodbank, or stop bank is a structure that is usually earthen and that often runs parallel to the course of a river in its floodplain or along low-lying coastlines. The purpose of a levee is to keep the course of rivers from changing and to protect against flooding of the area adjoining the river or coast. Levees can be naturally occurring ridge structures that form next to the bank of a river, or be an artificially constructed fill or wall that regulates water levels. Ancient civilizations in the Indus Valley, ancient Egypt, Mesopotamia and China all built levees. Today, levees can be found around the world, and failures of levees due to erosion or other causes can be major disasters.

Floodplain Land adjacent to a river which is flooded during periods of high discharge

A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge. The soils usually consist of clays, silts, sands, and gravels deposited during floods.

Braided river Network of river channels separated by small, and often temporary, islands

A braided river, or braided channel, consists of a network of river channels separated by small, often temporary, islands called braid bars or, in English usage, aits or eyots.

Brahmaputra River River in Tibet, India, and Bangladesh

The Brahmaputra, also known as the Yarlung Tsangpo in Tibet, the Siang/Dihang River in Arunachal Pradesh, and Luit in Assamese, is a trans-boundary river which flows through Tibet, India, and Bangladesh. It is the 9th largest river in the world by discharge, and the 15th longest.

Fluvial processes Processes associated with rivers and streams

In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluvioglacial is used.

Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.

Gully Landform created by running water and/or mass movement eroding sharply into soil

A gully is a landform created by running water, mass movement, or commonly a combination of both eroding sharply into soil or other relatively erodible material, typically on a hillside or in river floodplains or terraces. Gullies resemble large ditches or small valleys, but are metres to tens of metres in depth and width and are characterised by a distinct 'headscarp' or 'headwall' and progress by headward erosion. Gullies are commonly related to intermittent or ephemeral water flow usually associated with localised intense or protracted rainfall events, or snowmelt. Gullies can be formed and accelerated by cultivation practices on hillslopes in farmland, and they can develop rapidly in rangelands from existing natural erosion forms subject to vegetative cover removal and livestock activity.

Kobuk River River in Alaska, United States

The Kobuk River is a river located in the Arctic region of northwestern Alaska in the United States. It is approximately 280 miles (451 km) long. Draining a basin with an area of 12,300 square miles (32,000 km2), the Kobuk River is among the largest rivers in northwest Alaska with widths of up to 1,500 feet and flow at a speed of 3–5 miles per hour in its lower and middle reaches. The average elevation for the Kobuk River Basin is 1,300 feet (400 m) above sea level, ranging from near sea level to 11,400 feet. Topography includes low, rolling mountains, plains and lowlands, moderately high rugged mountainous land, and some gently sloped plateaus and highlands. The river contains an exceptional population of sheefish, a large predatory whitefish within the salmon family, found throughout the Arctic that spawns in the river's upper reaches during the autumn. A portion of the vast Western Arctic Caribou Herd utilize the Kobuk river valley as winter range.

Channel (geography) Type of landform in which part of a body of water is confined to a relatively narrow but long region

In physical geography, a channel is a type of landform consisting of the outline of a path of relatively shallow and narrow body of water or of other fluids, most commonly the confine of a river, river delta or strait. The word is cognate to canal, and sometimes takes this form, e.g. the Hood Canal.

Alluvial plain Region on which rivers have deposited sediment

An alluvial plain is a largely flat landform created by the deposition of sediment over a long period of time by one or more rivers coming from highland regions, from which alluvial soil forms. A floodplain is part of the process, being the smaller area over which the rivers flood at a particular period of time, whereas the alluvial plain is the larger area representing the region over which the floodplains have shifted over geological time.

Meander One of a series of curves in a channel of a matured stream

A meander is one of a series of regular sinuous curves in the channel of a river or other watercourse. It is produced as a watercourse erodes the sediments of an outer, concave bank and deposits sediments on an inner, convex bank which is typically a point bar. The result of this coupled erosion and sedimentation is the formation of a sinuous course as the channel migrates back and forth across the axis of a floodplain.

Streamflow, or channel runoff, is the flow of water in streams and other channels, and is a major element of the water cycle. It is one component of the movement of water from the land to waterbodies, the other component being surface runoff. Water flowing in channels comes from surface runoff from adjacent hillslopes, from groundwater flow out of the ground, and from water discharged from pipes. The discharge of water flowing in a channel is measured using stream gauges or can be estimated by the Manning equation. The record of flow over time is called a hydrograph. Flooding occurs when the volume of water exceeds the capacity of the channel.

An overbank is an alluvial geological deposit consisting of sediment that has been deposited on the floodplain of a river or stream by flood waters that have broken through or overtopped the banks. The sediment is carried in suspension, and because it is carried outside of the main channel, away from faster flow, the sediment is typically fine-grained. An overbank deposit usually consists primarily of fine sand, silt and clay. Overbank deposits can be beneficial because they refresh valley soils.

Stream load

Stream load is a geologic term referring to the solid matter carried by a stream. Erosion and bed shear stress continually remove mineral material from the bed and banks of the stream channel, adding this material to the regular flow of water. The amount of solid load that a stream can carry, or stream capacity, is measured in metric tons per day, passing a given location. Stream capacity is dependent upon the stream's velocity, the amount of water flow, and the gradation.

Stream Body of surface water flowing down a channel

A stream is a continuous body of surface water flowing within the bed and banks of a channel. Depending on its location or certain characteristics, a stream may be referred to by a variety of local or regional names. Long large streams are usually called rivers, while smaller, less voluminous and more intermittent streams are known as streamlets, brooks or creeks.

Alluvial river Type of river

An alluvial river is one in which the bed and banks are made up of mobile sediment and/or soil. Alluvial rivers are self-formed, meaning that their channels are shaped by the magnitude and frequency of the floods that they experience, and the ability of these floods to erode, deposit, and transport sediment. For this reason, alluvial rivers can assume a number of forms based on the properties of their banks; the flows they experience; the local riparian ecology; and the amount, size, and type of sediment that they carry.

Bedrock river Type of river

A bedrock river is a river that has little to no alluvium mantling the bedrock over which it flows. However, most bedrock rivers are not pure forms; they are a combination of a bedrock channel and an alluvial channel. The way one can distinguish between bedrock rivers and alluvial rivers is through the extent of sediment cover.

Channel patterns are found in rivers, streams, and other bodies of water that transport water from one place to another. Systems of branching river channels dissect most of the sub-aerial landscape, each in a valley proportioned to its size. Whether formed by chance or necessity, by headward erosion or downslope convergence, whether inherited or newly formed. Depending on different geological factors such as weathering, erosion, depositional environment, and sediment type, different types of channel patterns can form.

Riparian-zone restoration Ecological restoration of river banks and floodplains

Riparian-zone restoration is the ecological restoration of riparian-zonehabitats of streams, rivers, springs, lakes, floodplains, and other hydrologic ecologies. A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth; the habitats of plant and animal communities along the margins and river banks are called riparian vegetation, characterized by Aquatic plants and animals that favor them. Riparian zones are significant in ecology, environmental management, and civil engineering because of their role in soil conservation, their habitat biodiversity, and the influence they have on fauna and aquatic ecosystems, including grassland, woodland, wetland or sub-surface features such as water tables. In some regions the terms riparian woodland, riparian forest, riparian buffer zone, or riparian strip are used to characterize a riparian zone.

Meander cutoff

A meander cutoff is a natural form of a cutting or cut in a river occurs when a pronounced meander (hook) in a river is breached by a flow that connects the two closest parts of the hook to form a new channel, a full loop. The steeper drop in gradient (slope) causes the river flow gradually to abandon the meander which will silt up with sediment from deposition. Cutoffs are a natural part of the evolution of a meandering river. Rivers form meanders as they flow laterally downstream, see sinuosity.


  1. 1 2 "Mapping, Remote Sensing, and Geospatial Data: What is the difference between 'mountain', 'hill', and 'peak'; 'lake' and 'pond'; or 'river' and 'creek?'". United States Geological Survey . Retrieved 25 August 2019.
  2. "WordNet Search: River". The Trustees of Princeton University. Retrieved 2 October 2009.
  3. Basic Biology (16 January 2016). "River".
  4. see for example John Speed's atlas 'The Theatre of the Empire of Great Britaine' published in 1611 and 1612 and the UK 'Old Series' of Ordnance Survey maps (1817-1830)
  5. Walther, John V. (15 February 2013). Earth's Natural Resources. Jones & Bartlett Publishers. ISBN   978-1-4496-3234-2.
  6. Garde, R.J. (1995). History of fluvial hydraulics. New Age Publishers. p. 14. ISBN   978-81-224-0815-7. OCLC   34628134.
  7. Garde, R.J. (1995). History of fluvial hydraulics. New Age Publishers. p. 19. ISBN   978-81-224-0815-7. OCLC   34628134.
  8. "Sand River" in Iraq is actually a rapid movement of ice blocks. Tampabayreview.com. Retrieved on 14 July 2016.
  9. River Classification scheme. sepa.org.uk
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Further reading