A lagoon is a shallow body of water separated from a larger body of water by a narrow landform , such as reefs , barrier islands , barrier peninsulas, or isthmuses . Lagoons are commonly divided into coastal lagoons (or barrier 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.
30-403: Ahuriri Lagoon ( Māori : Te Whanganui-a-Orotū ) was a large tidal lagoon at Napier , on the east coast of New Zealand 's North Island , that largely drained when the area was raised by the 1931 Hawke's Bay earthquake . Before the earthquake, the lagoon stretched several kilometres from north to south, and covered roughly 4000 hectares (ha), or 40 km. The Tutaekuri River flowed into
60-466: A barrier peninsula upon which the town of Kitty Hawk is located, at the eastern edge of the sound, and part of the greater Outer Banks region. Roanoke Island is situated at the southeastern corner of the sound, where it connects to Pamlico Sound . Much of the water in the Albemarle Sound is brackish or fresh, as opposed to the saltwater of the ocean, as a result of river water pouring into
90-453: A common method of transportation through the swamps surrounding the Albemarle Sound throughout the history of the region. One ferry that linked the towns of Edenton and Mackeys, North Carolina , continued in service from 1734 to 1938, when a bridge was built across the Sound. Another, longer bridge of more than 3 miles (4.8 km) in length was built in 1990. Fishing was a major industry in
120-539: A lake is hu ( 湖 ), and a lagoon is xihu ( 潟湖 ). In the French Mediterranean several lagoons are called étang ("lake"). Contrariwise, several other languages have specific words for such bodies of water. In Spanish, coastal lagoons generically are laguna costera , but those on the Mediterranean coast are specifically called albufera . In Russian and Ukrainian, those on
150-501: A larger body of water by a shallow or exposed shoal , coral reef , or similar feature. Some authorities include fresh water bodies in the definition of "lagoon", while others explicitly restrict "lagoon" to bodies of water with some degree of salinity . The distinction between "lagoon" and "estuary" also varies between authorities. Richard A. Davis Jr. restricts "lagoon" to bodies of water with little or no fresh water inflow, and little or no tidal flow, and calls any bay that receives
180-422: A regular flow of fresh water an "estuary". Davis does state that the terms "lagoon" and "estuary" are "often loosely applied, even in scientific literature". Timothy M. Kusky characterizes lagoons as normally being elongated parallel to the coast, while estuaries are usually drowned river valleys, elongated perpendicular to the coast. Coastal lagoons are classified as inland bodies of water. When used within
210-458: Is actually the third-largest lake by area in the country. The brackish water lagoon may be thus explicitly identified as a "coastal lagoon" ( laguna costera ). In Portuguese, a similar usage is found: lagoa may be a body of shallow seawater, or a small freshwater lake not linked to the sea. Lagoon is derived from the Italian laguna , which refers to the waters around Venice ,
240-626: The Black Sea are liman ( лиман ), while the generic word is laguna ( Лагуна ). Similarly, in the Baltic , Danish has the specific Nor [ da ] , and German the specifics Bodden and Haff , as well as generic terms derived from laguna . In Poland these lagoons are called zalew ("bay"), in Lithuania marios ("lagoon, reservoir"). In Jutland several lagoons are known as fjord . In New Zealand
270-523: The Māori word hapua refers to a coastal lagoon formed at the mouth of a braided river where there are mixed sand and gravel beaches, while waituna , an ephemeral coastal waterbody, is neither a true lagoon, lake nor estuary. Some languages differentiate between coastal and atoll lagoons. In French, lagon [ fr ] refers specifically to an atoll lagoon, while coastal lagoons are described as étang [ fr ] ,
300-610: The Venetian Lagoon . Laguna is attested in English by at least 1612, and had been Anglicized to "lagune" by 1673. In 1697 William Dampier referred to a "Lagune or Lake of Salt water" on the coast of Mexico. Captain James Cook described an island "of Oval form with a Lagoon in the middle" in 1769. Atoll lagoons form as coral reefs grow upwards while the islands that the reefs surround subside, until eventually only
330-458: The Wadden Sea , have strong tidal currents and mixing. Coastal lagoons tend to accumulate sediments from inflowing rivers, from runoff from the shores of the lagoon, and from sediment carried into the lagoon through inlets by the tide. Large quantities of sediment may be occasionally be deposited in a lagoon when storm waves overwash barrier islands. Mangroves and marsh plants can facilitate
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#1732783512748360-515: The West Indies in exchange for products such as tobacco (a major export of the southern colonies), herring , and lumber. In 1663, King Charles II of England designated Albemarle Sound as part of the Province of Carolina ; it was assigned to eight Lords Proprietors . One of these royal beneficiaries was George Monck, 1st Duke of Albemarle , for whom the sound is named. Ferries were
390-531: The Albemarle Sound from the colonial period. In late spring, when the fish runs started, planters set enslaved workers to fish for shad , striped bass , and herring . Fishermen sometimes had enormous nets, with some more than a mile (1600 m) long, and they were frequently staffed 24 hours a day. Herring was cut and salted for export to Europe, while shad was packed in ice and shipped up the Chowan River to be sold in northern colonies. In more recent times of
420-631: The English Albemarle Settlements . Many inland Tidewater communities along the Albemarle today are classified as part of the Inner Banks region of the state. The indigenous Pamlico and their ancestors lived in the region for thousands of years. They traveled the sound in dugout canoes , and trapped fish . The Pamlico often set up seasonal fishing camps for this purpose, retreating inland in winter weather. In 1586
450-662: The accumulation of sediment in a lagoon. Benthic organisms may stabilize or destabilize sediments. Albemarle Sound Albemarle Sound ( / ˈ æ l b ə ˌ m ɑː r l / ) 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 ,
480-626: The context of a distinctive portion of coral reef ecosystems, the term "lagoon" is synonymous with the term "back reef" or "backreef", which is more commonly used by coral reef scientists to refer to the same area. Many lagoons do not include "lagoon" in their common names. Currituck , Albemarle and Pamlico Sounds in North Carolina , Great South Bay between Long Island and the barrier beaches of Fire Island in New York , Isle of Wight Bay , which separates Ocean City, Maryland from
510-498: The earthquake drained much of the lagoon, leaving a smaller estuary . Land reclamation and drainage work further reduced the estuary to its present size of 470 ha. Māori named the lagoon Te Whanganui-a-Orotū (the Great Harbour of Orotū) after the chief Te Orotū. It was an important food source for Māori and supported a large population. European settlers established Napier on Scinde Island (present day Bluff Hill ) in
540-719: The entire body of water now known as Albemarle Sound ). The long stretch of water from near the Virginia state line south to around the Currituck County southern boundary is known as the Currituck Sound . Albemarle Sound forms part of the Atlantic Intracoastal Waterway . Early English colonists, mostly migrants from Virginia, settled along its in the first permanent European settlements in what became North Carolina; these were known as
570-460: The first European explorers sailed up the fifty-five-mile (89 km) length of the Albemarle Sound. Half a century later, the first European settlers came south from Virginia , establishing agricultural and trading colonies along the shores of the Sound. The Albemarle Sound soon became an important thoroughfare: small trading ships called coasters carried cargo to and from other colonies, and larger merchant ships brought spices, silks, and sugars from
600-597: The generic word for a still lake or pond. In Vietnamese, Đầm san hô refers to an atoll lagoon, whilst Đầm phá is coastal. In Latin America, the term laguna in Spanish, which lagoon translates to, may be used for a small fresh water lake in a similar way a creek is considered a small river. However, sometimes it is popularly used to describe a full-sized lake , such as Laguna Catemaco in Mexico, which
630-424: The harbour, and it soon became a prosperous region on New Zealand's east coast. Napier's growth then halted, as there was not enough flat land to build on. The southern end of the lagoon stretched between Scinde Island and the mainland, separating Napier from the settlement of Taradale, and many people moving into the region chose Taradale over Napier because of the abundance of land. In the 1931 Hawke's Bay earthquake
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#1732783512748660-436: The lagoon was uplifted, exposing roughly 30 km (3000ha) of seabed. This included a new land bridge between Napier and Taradale. The towns grew over the years and Taradale amalgamated with Napier, forming Napier City, in 1968. Most of what was the lagoon is now low-lying land. Hawke's Bay Airport and suburbs of Napier are built on part of it. Much of the rest is used for agriculture. A broad shallow river channel runs along
690-630: The lagoon. Lagoons with little or no interchange with the open ocean, little or no inflow of fresh water, and high evaporation rates, such as Lake St. Lucia , in South Africa , may become highly saline. Lagoons with no connection to the open ocean and significant inflow of fresh water, such as the Lake Worth Lagoon in Florida in the middle of the 19th century, may be entirely fresh. On the other hand, lagoons with many wide inlets, such as
720-556: The land along the coast). Coastal lagoons do not form along steep or rocky coasts, or if the range of tides is more than 4 metres (13 ft). Due to the gentle slope of the coast, coastal lagoons are shallow. A relative drop in sea level may leave a lagoon largely dry, while a rise in sea level may let the sea breach or destroy barrier islands, and leave reefs too deep underwater to protect the lagoon. Coastal lagoons are young and dynamic, and may be short-lived in geological terms. Coastal lagoons are common, occurring along nearly 15 percent of
750-407: The reefs remain above sea level. Unlike the lagoons that form shoreward of fringing reefs, atoll lagoons often contain some deep (>20 m (66 ft)) portions. Coastal lagoons form along gently sloping coasts where barrier islands or reefs can develop offshore, and the sea-level is rising relative to the land along the shore (either because of an intrinsic rise in sea-level, or subsidence of
780-627: The rest of Worcester County, Maryland , Banana River in Florida , US, Lake Illawarra in New South Wales , Australia, Montrose Basin in Scotland , and Broad Water in Wales have all been classified as lagoons, despite their names. In England, The Fleet at Chesil Beach has also been described as a lagoon. In some languages the word for a lagoon is simply a type of lake: In Chinese
810-466: The sound. Some small portions of the Albemarle have been given their own "sound" names to distinguish these bodies of water from other parts of the large estuary. The Croatan Sound , for instance, lies between mainland Dare County and Roanoke Island. The water bordering the eastern shore of the island to the Outer Banks is commonly referred to as Roanoke Sound (this is also a historical name for
840-596: The southern end, and the Esk River into the northern end. Following the earthquake, the Esk was no longer able to flow into the lagoon and ran more directly to the sea. The Tūtaekurī still flowed into the lagoon after the earthquake but it caused flooding for the next few years, and by the end of the 1930s it had been diverted away from the lagoon to enter the sea at the mouth of the Ngaruroro River . The land rise in
870-445: The western edge and across the southern half of the reclaimed land, flowing into Hawke Bay at Ahuriri Estuary, to the west of the suburb of Ahuriri and Bluff Hill. The suburb of Westshore occupies a thin strip between the sea and State Highway 2 . 39°28′S 176°52′E / 39.467°S 176.867°E / -39.467; 176.867 Lagoon Lagoons are shallow, often elongated bodies of water separated from
900-459: The world's shorelines. In the United States, lagoons are found along more than 75 percent of the Eastern and Gulf Coasts . Coastal lagoons can be classified as leaky, restricted, or choked. Coastal lagoons are usually connected to the open ocean by inlets between barrier islands. The number and size of the inlets, precipitation, evaporation, and inflow of fresh water all affect the nature of
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