The Haringvliet is a large

inlet An inlet is a (usually long and narrow) indentation of a shoreline, such as a small arm, bay, sound, fjord, lagoon or marsh, that leads to an enclosed larger body of water such as a lake, estuary, gulf or marginal sea. Overview In marine geogra ...

of the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...

, in the province of

South Holland South Holland ( nl, Zuid-Holland ) is a province of the Netherlands with a population of over 3.7 million as of October 2021 and a population density of about , making it the country's most populous province and one of the world's most densely ...

in the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

. It is an important

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

of the Rhine-Meuse delta. Near

Numansdorp Numansdorp is a town and former municipality in the province South Holland in the Netherlands and is located on the island Hoeksche Waard near the Hollands Diep. On 1 January 1984, the municipalities Numansdorp and Klaaswaal were merged into one ...

, the

Hollands Diep Hollands Diep ( pre-1947 spelling: Hollandsch Diep) is a wide river in the Netherlands and an estuary of the Rhine and Meuse rivers. Through the Scheldt-Rhine Canal it connects to the Scheldt river and Antwerp. The Bergse Maas river and the N ...

splits into the Haringvliet and the

Volkerak The Volkerak is a body of water in the Netherlands. It is part of the Rhine–Meuse–Scheldt delta, and is situated between the island Goeree-Overflakkee to the north-west and the Dutch mainland to the south and east. The western part of the Volk ...

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

. It is closed off near

Goedereede Goedereede () is a little town and former municipality in the western Netherlands, in the province of South Holland. The former municipality had a population of about 11,000 in 2010. It consisted of the west part of the island of Goeree-Overfla ...

from the

by the

Haringvlietdam The Haringvliet sluices are a construction that closed off the estuary of the Haringvliet, Netherlands, as part of the Delta Works. The structure consists of 17 sluices, several kilometres of dam and a shipping lock. The northernmost of the Delta ...

, which provides a

road A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation. There are many types of ...

connection between the

island An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island ...

of Voorne to the north and the island of

Goeree-Overflakkee Goeree-Overflakkee () is the southernmost delta island of the province of South Holland, Netherlands. It is separated from Voorne-Putten and Hoeksche Waard by the Haringvliet, from the mainland of North Brabant by the Volkerak, and from Schouwen ...

to the south. The dam with its sluices was built as part of the

Delta Works The Delta Works ( nl, Deltawerken) is a series of construction projects in the southwest of the Netherlands to protect a large area of land around the Rhine–Meuse–Scheldt delta from the sea. Constructed between 1954 and 1997, the works con ...

sea barrier protection works. The Haringvliet estuary contains the island of

Tiengemeten Tiengemeten is an island in the Dutch province of South Holland. It is a part of the municipality of Hoeksche Waard and lies about south of Spijkenisse. Before 1984 the island was administratively split between Goudswaard and Zuid-Beijerland, ...

, which is separated from the

river island River Island is a London-based, multi-channel fashion brand, founded in 1948 by Bernard Lewis. The retailer has a presence in over 125 of worldwide markets, in stores and online. Best known for its trend focused womenswear offering, River Isla ...

Hoeksche Waard The Hoekse Waard (; pre-1947 spelling: Hoeksche Waard) is an island between the Oude Maas, Dordtsche Kil, Hollands Diep, Haringvliet and Spui rivers in the province of South Holland in the Netherlands. The island, part of the namesake municipal ...

by the Vuile Gat

strait A strait is an oceanic landform connecting two seas or two other large areas of water. The surface water generally flows at the same elevation on both sides and through the strait in either direction. Most commonly, it is a narrow ocean channe ...

History

The Haringvliet was formed as a result of the extensive flooding event of 1216, which breached the dunes of Voorne and created a deep saltwater inlet. During a second flooding event, the

St. Elizabeth flood The St. Elizabeth's flood of 1421 was a flooding of the Grote Hollandse Waard, an area in what is now the Netherlands. It takes its name from the feast day of Saint Elisabeth of Hungary which was formerly 19 November. It ranks 20th on the list of ...

s of 1421, this inlet connected to the

Merwede The Merwede () etymology uncertain, possibly derived from the ancient Dutch language, Dutch ''Merwe'' or ''Merowe'', a word meaning "wide water") is the name of several connected stretches of river in the Netherlands, between the cities of Woudrich ...

and became an important estuary of the

Rhine ), Surselva, Graubünden, Switzerland , source1_coordinates= , source1_elevation = , source2 = Rein Posteriur/Hinterrhein , source2_location = Paradies Glacier, Graubünden, Switzerland , source2_coordinates= , so ...

and

Meuse The Meuse ( , , , ; wa, Moûze ) or Maas ( , ; li, Maos or ) is a major European river, rising in France and flowing through Belgium and the Netherlands before draining into the North Sea from the Rhine–Meuse–Scheldt delta. It has a t ...

rivers. It used to be ecologically rich, and its brackish waters, fed by both rivers and sea, supported a healthy population of

seals Seals may refer to: * Pinniped, a diverse group of semi-aquatic marine mammals, many of which are commonly called seals, particularly: ** Earless seal, or "true seal" ** Fur seal * Seal (emblem), a device to impress an emblem, used as a means of a ...

. It also provided an access point for migrating fish like

salmon Salmon () is the common name for several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the family (biology), family Salmonidae, which are native to tributary, tributaries of the ...

and

sturgeon Sturgeon is the common name for the 27 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretace ...

. As a result of the

North Sea flood of 1953 The 1953 North Sea flood was a major flood caused by a heavy storm surge that struck the Netherlands, north-west Belgium, England and Scotland. Most sea defences facing the surge were overwhelmed, causing extensive flooding. The storm and flo ...

the Haringvliet was closed off by the Haringvlietdam. The Haringvliet lost its estuarine characteristics and became a freshwater lake. Because of that, the seals are gone and migrating fish can only enter the Rhine-Meuse Delta through the busy and heavy industrialised

Nieuwe Waterweg The Nieuwe Waterweg ("New Waterway") is a ship canal in the Netherlands from het Scheur (a branch of the Rhine-Meuse-Scheldt delta) west of the town of Maassluis to the North Sea at Hook of Holland: the Maasmond, where the Nieuwe Waterweg conn ...

. There are plans to permanently open a few of the Haringvliet sluices, to partly restore the ecosystem.

References

{{coord, 51, 46, 18, N, 4, 12, 57, E, region:NL_type:waterbody_source:kolossus-nlwiki, display=title Rhine–Meuse–Scheldt delta Ramsar sites in the Netherlands Natura 2000 in the Netherlands Goeree-Overflakkee Hoeksche Waard Lakes of the Netherlands