River mouth

A river mouth is the part of a river where the river debouches into another river, a lake, a reservoir, a sea, or an ocean.[1]

The port and city are the southern terminus of the Suez Canal which flows through Egypt and debouches into the Mediterranean Sea near Port Said.

Water motion

The water from a river can enter the receiving body in a variety of different ways.[1] The motion of a river is influenced by the relative density of the river compared to the receiving water, the rotation of the earth, and any ambient motion in the receiving water, such as tides or seiches.[2]

If the river water has a higher density than the surface of the receiving water, the river water will plunge below the surface. The river water will then either form an underflow or an interflow within the lake. However, if the river water is lighter than the receiving water, as is typically the case when fresh river water flows into the sea, the river water will float along the surface of the receiving water as an overflow.

Alongside these advective transports, inflowing water will also diffuse.[1]


At the but of a river, the change in flow condition can cause the river to drop any sediment it is carrying. This sediment deposition can generate a variety of landforms, such as deltas, sand bars, spits, and tie channels.[3]

Cultural influence

Many places in the United Kingdom take their names from their positions at the mouths of rivers, such as Plymouth (i.e. mouth of the Plym River), Sidmouth (i.e. mouth of the Sid River), and Great Yarmouth (i.e. mouth of the Yare River); in Celtic, the term is Aber or Inver.

See also


  1. ^ a b c Charles, Hogg, (2014-06-12). "The flow of rivers into lakes: Experiments and models". doi:10.17863/cam.32.
  2. ^ Ma, Yanxia (2009). Continental Shelf Sediment Transport and Depositional Processes on an Energetic, Active Margin: the Waiapu River Shelf, New Zealand. pp. 2, 19.
  3. ^ Rowland, J. C.; Dietrich, W. E.; Day, G.; Parker, G. (2009). "Formation and maintenance of single‐thread tie channels entering floodplain lakes: Observations from three diverse river systems". Journal of Geophysical Research. 114 (F2). doi:10.1029/2008JF001073.
Alexandria, Eastern Cape

Alexandria is a small farming town in the Eastern Cape of South Africa and is situated 100 km North East of Port Elizabeth on the way to Bushman's River Mouth, Kenton-on-Sea and Port Alfred. Alexandria is part of the Ndlambe Local Municipality in the Sarah Baartman District Municipality of the Eastern Cape.

It might have been established by the Dutch colonial government in the late 18th century, but was named Alexandria in 1856 after Reverend Alexander Smith. It has a warm temperate climate and is unusual in southern Africa in having no distinct dry or wet season, with rain received throughout the year.

Alexandria is one of the most important chicory producing areas in South Africa and is also known for pineapple production and dairy farming. The Alexandria area also includes the Alexandria State Forest, known as Langebos to the locals, which is a narrow stretch of pristine indigenous forest bordering the Alexandria dune field, one of the largest active dune fields in the world. The Woody Cape Nature Reserve, which stretches from the Sundays River mouth to the Bushman's River mouth and includes the dune field and the indigenous forest, has been incorporated into the Addo Elephant National Park.

Apyu, California

Apyu is a former Karok settlement in Humboldt County, California. It was located about 1 mile (1.6 km) above the Salmon River mouth near the upper rapids above the mouth of the Salmon across from Ishipishi. Its precise location is unknown. It was approximately 0.5 miles (0.80 km) east of Somes Bar, a community in Siskiyou County.

Brawley Seismic Zone

The Brawley Seismic Zone (BSZ), also known as the Brawley fault zone, is a predominantly extensional tectonic zone that connects the southern terminus of the San Andreas Fault with the Imperial Fault in Southern California. The BSZ is named for the nearby town of Brawley in Imperial County, California, and the seismicity there is characterized by earthquake swarms.

Bushman's River Mouth

Bushman's River Mouth (Afrikaans Boesmansriviermond) is a town in Ndlambe Local Municipality in the Eastern Cape province of South Africa.

The village is 25 km from Port Alfred, on the west bank of the Bushman's River, just across the river from Kenton-on-Sea.A well-known holiday resort, it is the site of many shipwrecks, the best-known of them being the Volo, a Norwegian barque wrecked near the river mouth in 1896.It was established in 1897 by farmers from nearby towns (Paterson, Cookhouse, Somerset East and Cradock) when they were granted permission to camp along the banks of the Bushmans River during the Christmas holiday season. Land leases during the early 1900s led to private land ownership, and modern development, though electricity and running water only became available in the 1980s,The Dias Cross Memorial at nearby Kwaaihoek is a provincial heritage site erected to mark the location of the padrão, or stone pillar, planted by Portuguese sailors led by Bartolomeu Dias.

East Machias River

The East Machias River is a river in Washington County, Maine. From the outlet of Crawford Lake (45°00′43″N 67°35′12″W) in Crawford, it runs 35.8 miles (57.6 km) southeast to the estuary of the Machias River at the head of Machias Bay. The river mouth is on the border between the towns of East Machias and Machiasport.

Guilderton, Western Australia

Guilderton is a small coastal town north of Perth, Western Australia at the mouth of the Moore River in the Shire of Gingin.

It was originally known as Gabbadah, an Aboriginal term meaning "mouthful of water" until its gazetting as a town in 1951. The river mouth regularly opens and closes depending on the seasons, and alternates between a closed lagoon and a tidal estuary.

The town is a popular holiday destination for Perth residents who commonly refer to it as Moore River.

Imperial Fault Zone

The Imperial Fault Zone is a system of geological faults located in Imperial County in the Southern California region, and adjacent Baja California state in Mexico. It cuts across the border between the United States and Mexico.

Klasies River Caves

The Klasies River Caves are a series of caves located to the east of the Klasies River mouth on the Tsitsikamma coast in the Humansdorp district of Eastern Cape Province, South Africa. The three main caves and two shelters at the base of a high cliff have revealed evidence of middle stone age-associated human habitation from approximately 125,000 years ago. The 20 metres (66 ft) thick deposits were accumulated from 125,000 years ago. Around 75,000 years ago, during cave remodelling, the stratigraphic sediments were moved out into external middens.

In 2015, the South African government submitted a proposal to add the caves to the list of World Heritage Sites.From 1960, Ronald Singer, Ray Inskeep, John Wymer, Hilary Deacon, Richard Klein and others suggested the excavation yielded the earliest known evidence of behaviourally modern humans.

Further analysis suggested that the specimens fall "outside the range of modern variation".


A lagoon is a shallow body of water separated from a larger body of water by barrier islands or reefs. Lagoons are commonly divided into coastal lagoons and atoll lagoons. They have also been identified as occurring on mixed-sand and gravel coastlines. There is an overlap between bodies of water classified as coastal lagoons and bodies of water classified as estuaries. Lagoons are common coastal features around many parts of the world.

List of longest rivers of the United States (by main stem)

The main stems of 38 rivers in the United States are at least 500 miles (800 km) long. The main stem is "the primary downstream segment of a river, as contrasted to its tributaries". The United States Geological Survey (USGS) defines a main-stem segment by listing coordinates for its two end points, called the source and the mouth. Some well-known rivers like the Atchafalaya, Willamette, and Susquehanna are not included in this list because their main stems are shorter than 500 miles.

Seven rivers in this list cross or form international boundaries. Two—the Yukon and Columbia rivers—begin in Canada and flow into the United States. Three—the Milk and Saint Lawrence rivers and the Red River of the North—begin in the United States and flow into Canada. Of these, only the Milk River crosses the international border twice, leaving and then re-entering the United States. Two rivers, the Colorado and the Rio Grande, begin in the United States and flow into or form a border with Mexico. In addition, the drainage basins of the Mississippi and Missouri rivers extend into Canada, and the basin of the Gila River extends into Mexico.Sources report hydrological quantities with varied precision. Biologist and author Ruth Patrick, describing a table of high-discharge U.S. rivers, wrote that data on discharge, drainage area, and length varied widely among authors whose works she consulted. "It seems," she said, "that the wisest course is to regard data tables such as the present one as showing the general ranks of rivers, and not to place too much importance on minor (10–20%) differences in figures."

List of longest streams of Oregon

Seventy-seven rivers and creeks of at least 50 miles (80 km) in total length are the longest streams of the U.S. state of Oregon. All of these streams originate in the United States except the longest, the Columbia, which begins in the Canadian province of British Columbia and flows 1,249 miles (2,010 km) to the sea near Astoria. The second-longest, the Snake River, which at 1,078 miles (1,735 km) is the only other stream of more than 1,000 miles (1,600 km) on the list, begins in Wyoming and flows through parts of Idaho and Washington, as well as Oregon. Some of the other streams also cross borders between Oregon and California, Nevada, Idaho, or Washington, but the majority flow entirely within Oregon.

The Atlas of Oregon ranks 31 rivers in the state by average streamflow; the top five are the Columbia, Snake, Willamette, Santiam, and Umpqua. Not all Oregon rivers with high average flows are on this list of longest streams because neither their main stems nor any of their tributaries (including what are called "forks") are at least 50 miles (80 km) long. High-flow streams mentioned in the Atlas but not included in this long-stream list are the Metolius, Hood, Youngs, and Coos rivers. On the other hand, the list includes four low-flow intermittent streams—Dry River, Rattlesnake Creek, Rock Creek, and Dry Creek—that cross parts of the Oregon High Desert.

The direction of Oregon stream flow is influenced by four major drainage divides: the Oregon Coast Range on the west, the Cascade Range further inland, the Klamath–Siskiyou Mountains in the southwest, and the Blue Mountains in the northeast. One set of streams, including the Nehalem River, flows directly into the Pacific Ocean or into larger streams flowing directly to the Pacific; other streams, such as the Deschutes River, flow into the Columbia River or its tributaries. A third set, including the Klamath River and its tributaries, originates in Oregon, but its waters eventually flow into northern California before reaching the ocean. Other streams like the Donner und Blitzen River flow into closed basins, such as Malheur Lake, that have no outlet to the sea.Source data for the table below came from topographic maps created by the United States Geological Survey and published on-line by TopoQuest, and from the Atlas of Oregon; the Oregon Atlas and Gazetteer; two federally produced geographic information system (GIS) datasets—the National Hydrography Dataset and the National Watershed Boundary Dataset—and other sources as noted. In the table, total lengths are given in miles (mi) and kilometers (km), and elevations are in feet (ft) and meters (m).

List of rivers of South Africa

This is a list of rivers in South Africa.

It is quite common to find the Afrikaans word -rivier as part of the name. Another common suffix is "-kamma", from the Khoisan term for "river"

(often tautologically the English term "river" is added to the name). The Zulu word amanzi (water) also forms part of some river names.

The Afrikaans term spruit (compare spring) often labels small rivers.


The Mississauga are a subtribe of the Anishinaabe-speaking First Nations people located in southern Ontario, Canada. They are closely related to the Ojibwe. The name "Mississauga" comes from the Anishinaabe word Misi-zaagiing, meaning "[Those at the] Great River-mouth." It is closely related to the Ojibwe word Misswezahging, which means ‘a river with many outlets.’

New York Bay

New York Bay is the collective term for the marine areas surrounding the river mouth of the Hudson River into the Atlantic Ocean, in New Jersey and New York City.

Orange River

The Orange River (from afrikaans/Dutch: Oranjerivier) is the longest river in Lesotho and the Orange River Basin extends extensively into South Africa, Namibia and Botswana to the north. It rises in the Drakensberg mountains in Lesotho, flowing westwards through South Africa to the Atlantic Ocean. The river forms part of the international borders between South Africa and Namibia and between South Africa and Lesotho, as well as several provincial borders within South Africa. Except for Upington, it does not pass through any major cities. The Orange River plays an important role in the South African economy by providing water for irrigation and hydroelectric power. The river was named the Orange River in honour of the Dutch ruling family, the House of Orange, by the Dutch explorer Robert Jacob Gordon. Other names include Gariep River (used by the Khoi people), Groote River or Senqu River (used in Lesotho).

Pambula Beach, New South Wales

Pambula Beach is a town in New South Wales, Australia not far from Pambula. At the 2016 census, Pambula Beach had a population of 654 people.The Holiday Hub tourist park is one of the major attractions for the township.

There are three surfing beaches. 1 - The Main Beach, Pambula Beach, is located in front of the Pambula Beach Holiday Hub and the surf club next door. It is the most popular of all the beaches in the town and the beach curves around the bay until it becomes Main Beach in the nearby township of Merimbula. 2 - south past the coastal rocks and cliffs, is Lions Beach. Behind the beach lays Lions Park, with a barbecue and picnic area. 3 - The 250 metres (820 ft) long beach ends at the mouth of the Pambula River: or The River Mouth. This surfing spot, named for the former sand banks, has been a surfing spot in the region. Today, however, the River Mouth suffers from lack of swell and insufficient sand banks.

Plum River

The Plum River is a tributary of the Mississippi River, about 46.6 miles (75.0 km) long, in northwestern Illinois in the United States. It rises in Jo Daviess County and flows generally south-southwestwardly into Carroll County, where it joins the Mississippi at Savanna. Among its several short tributaries are:

The East Plum River, which rises in Stephenson County and flows southwestwardly into Carroll County, joining the Plum at 42°10′16″N 90°01′20″W

The Muddy Plum River, which flows for its entire length in Jo Daviess County. It joins the Plum River at 42°13′35″N 90°01′45″W

The Middle Fork Plum River joins the Plum River at 42°16′29″N 90°02′12″W

The North Fork Plum River has its confluence with the Plum River at 42°15′46″N 90°02′33″W

River delta

A river delta is a landform created by deposition of sediment that is carried by a river as the flow leaves its mouth and enters slower-moving or stagnant water. This occurs where a river enters an ocean, sea, estuary, lake, reservoir, or (more rarely) another river that cannot carry away the supplied sediment. The size and shape of a delta is controlled by the balance between watershed processes that supply sediment, and receiving basin processes that redistribute, sequester, and export that sediment. The size, geometry, and location of the receiving basin also plays an important role in delta evolution. River deltas are important in human civilization, as they are major agricultural production centers and population centers. They can provide coastline defense and can impact drinking water supply. They are also ecologically important, with different species' assemblages depending on their landscape position.

Xiang River

The Xiang River is the chief river of the Lake Dongting drainage system of the middle Yangtze, the largest river in Hunan Province, China. It is the 2nd largest tributary (after Min River) in terms of surface runoff, the 5th largest tributary by drainage area of the Yangtze tributaries. The river flows generally northeast through Guangxi and Hunan two provinces, its tributaries reach into Jiangxi and Guangdong.

Traditionally, it was regarded that the West (left) Branch is the Main Stream of the Upper Xiang, which rises in Haiyang Mountains between xing'an and Lingchuan counties of Guangxi. According to the 1st national water census of China in 2011, the East Branch Xiao River originating from Lanshan County of Hunan, was identified as the Main Stem of the Upper Xiang. The Ping Island of Yongzhou is the meeting of the two streams, the West source originating from Guangxi and the East source of the Xiao River originating from Lanshan County of Hunan.With the tributaries, the Xiang has a river basin area of 94,721 square kilometres (36,572 sq mi), of which Hunan has an area of 85,383 square kilometres (32,967 sq mi). In a situation of Guangxi source, the Xiang has a length of 844 kilometres (524 mi); In another situation of Xiao River as the main source stream, the Xiang has a length of 948 kilometres (589 mi).

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