The Étang de Thau (; oc, Estanh de Taur) or Bassin de Thau is the largest of a string of

lagoon 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'') a ...

s (''étangs'') that stretch along the French coast from the

Rhône The Rhône ( , ; wae, Rotten ; frp, Rôno ; oc, Ròse ) is a major river in France and Switzerland, rising in the Alps and flowing west and south through Lake Geneva and southeastern France before discharging into the Mediterranean Sea. At Ar ...

river to the foothills of the

Pyrenees The Pyrenees (; es, Pirineos ; french: Pyrénées ; ca, Pirineu ; eu, Pirinioak ; oc, Pirenèus ; an, Pirineus) is a mountain range straddling the border of France and Spain. It extends nearly from its union with the Cantabrian Mountains to C ...

and the border to

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

in the

Languedoc-Roussillon Languedoc-Roussillon (; oc, Lengadòc-Rosselhon ; ca, Llenguadoc-Rosselló) is a former administrative region of France. On 1 January 2016, it joined with the region of Midi-Pyrénées to become Occitania. It comprised five departments, and ...

. Although it has a high salinity, it is considered the second largest lake in France.

Description

Barrou Neighbourhood, Étang de Thau, Sète 01

It is about 21 km long and 8 km wide, with an area of . The mean depth of the lagoon is 4.5 m, but in the central navigation channel it can be 10 m deep. Near

Bouzigues Bouzigues (; ''Bosigas'' in Occitan) is a commune in the Hérault department in southern France. Population See also *Communes of the Hérault department *Étang de Thau The Étang de Thau (; oc, Estanh de Taur) or Bassin de Thau is th ...

there is a 100-metre diameter depression of 30 metres. This 'Fosse de la Vise' is the source of a hot spring that feeds the spa in Balaruc. Its size and depth, which distinguish it from other lagoons of the region, is explained by the

geomorphology Geomorphology (from Ancient Greek: , ', "earth"; , ', "form"; and , ', "study") is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or n ...

of the region: it is the

syncline In structural geology, a syncline is a fold with younger layers closer to the center of the structure, whereas an anticline is the inverse of a syncline. A synclinorium (plural synclinoriums or synclinoria) is a large syncline with superimpose ...

formed from

folding Fold, folding or foldable may refer to: Arts, entertainment, and media * ''Fold'' (album), the debut release by Australian rock band Epicure * Fold (poker), in the game of poker, to discard one's hand and forfeit interest in the current pot *Abov ...

which produced the corresponding

anticline In structural geology, an anticline is a type of fold that is an arch-like shape and has its oldest beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex up in which the hinge or crest is the ...

of the Gardiole in the north east. Until relatively recently the lagoons from Marseillan to the

were a continuous stretch of inland waterway. Early settlers described this as "une petite mer intérieure et tranquille" ("a small sea, inner and quiet"). It provided access to, in particular, Marseillan—a

fishing village A fishing village is a village, usually located near a fishing ground, with an economy based on catching fish and harvesting seafood. The continents and islands around the world have coastlines totalling around 356,000 kilometres (221,000 m ...

that became a trade centre. Linked, now, by the

Canal du Rhône à Sète The Canal du Rhône à Sète (lit. "canal from the Rhône to Sète") is a canal in southern France, which connects the Étang de Thau in Sète to the Rhône River in Beaucaire, Gard. The canal is made up of two previously constructed canals, the ...

to the river Rhône and by the

Canal du Midi The Canal du Midi (; ) is a long canal in Southern France (french: le Midi). Originally named the ''Canal royal en Languedoc'' (Royal Canal in Languedoc) and renamed by French revolutionaries to ''Canal du Midi'' in 1789, the canal is considere ...

Bordeaux Bordeaux ( , ; Gascon oc, Bordèu ; eu, Bordele; it, Bordò; es, Burdeos) is a port city on the river Garonne in the Gironde department, Southwestern France. It is the capital of the Nouvelle-Aquitaine region, as well as the prefectur ...

via

Toulouse Toulouse ( , ; oc, Tolosa ) is the prefecture of the French department of Haute-Garonne and of the larger region of Occitania. The city is on the banks of the River Garonne, from the Mediterranean Sea, from the Atlantic Ocean and from Par ...

, the lagoon also has access to the

Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...

Sète Sète (; oc, Seta, ), also historically spelt ''Cette'' (official until 1928) and ''Sette'', is a commune in the Hérault department, in the region of Occitania, southern France. Its inhabitants are called ''Sétois'' (male) and ''Sétoises' ...

. There is also a small canal (''le canal des Allemands'' or the ''pisse-saume'') that links the western end to the sea at Marseillan Plage. This canal is only suitable for small craft since both road and railway bridges restrict height. To the east, between Balaruc and Sète, the borders of the lagoon are largely industrial. The south bank is formed by the coastal strip from Sète to

Cap d'Agde Cap d'Agde () is a seaside resort on France's Mediterranean coast. It is located in the commune of Agde, in the Hérault department within the region of Occitanie. Cap d'Agde was planned by architect Jean Le Couteur as part of one of the large ...

. The northern side has villages dedicated to fishing and the production of shellfish. There are harbours in the towns of Marseillan, Mèze and Bouzigues, with smaller ports dedicated to shellfish on the northern shore. There is significant variation in the rainfall in the catchment basin for the lagoon, both seasonally and between years. The annual precipitation can range from 200 to 1,000 mm per year. As a result, the water temperature and salinity have extensive ranges. Water temperature ranges from 3 °C to 29 °C, with salinities of 27

psu PSU may refer to: Organizations Military *Police Support Unit, a paramilitary wing of the Zimbabwe Republic Police *Port Security Unit, a U.S. Coast Guard expeditionary force protection unit Political parties * Parti Socialiste Unifié (disambig ...

to 40 psu. The salinity changes during the year with lows from February to June and peaks in July to January.

Administration

Located between the towns of

and Marseillan in the

Hérault Hérault (; oc, Erau, ) is a department of the region of Occitania, Southern France. Named after the Hérault River, its prefecture is Montpellier. It had a population of 1,175,623 in 2019.département In the administrative divisions of France, the department (french: département, ) is one of the three levels of government under the national level ("territorial collectivity, territorial collectivities"), between the regions of France, admin ...

, the Étang de Thau is shared administratively by the

communes An intentional community is a voluntary residential community which is designed to have a high degree of social cohesion and teamwork from the start. The members of an intentional community typically hold a common social, political, relig ...

of (running clockwise): Balaruc-le-Vieux,

Balaruc-les-Bains Balaruc-les-Bains (; oc, Los Banhs de Balaruc) is a commune in the Hérault department in the Occitanie region in southern France. Population See also *Communes of the Hérault department * Balaruc *Étang de Thau The Étang de Thau ( ...

Frontignan Frontignan (; ) is a commune in the Hérault department in southern France. Frontignan is renowned for its AOC wine, the Muscat de Frontignan, a sweet wine made solely from the Muscat grape variety. Geography Frontignan is located in the ...

, Sète, Marseillan,

Mèze Mèze (; oc, Mesa; phn, Mansa) is a commune in the Hérault department in southern France. Its inhabitants are called ''Mézois''. Geography Situated on the étang de Thau, Mèze shares with Bouzigues its historic role as the oyster capital ...

, Loupian and

Economy and natural resources

As the lagoon is open to the sea, it has fish such as the

gilt-head bream The gilt-head (sea) bream (''Sparus aurata''), known as Orata in antiquity and still today in Italy and Tunisia (known as "Dorada" in Spain, "Dourada" in Portugal and "Dorade Royale" in France), is a fish of the bream family Sparidae found in th ...

(''dorade''), the meagre (''maigre'', a kind of croaker) and the

sea bass Sea bass is a common name for a variety of different species of marine fish. Many fish species of various families have been called sea bass. In Ireland and the United Kingdom, the fish sold and consumed as sea bass is exclusively the European ba ...

. The lagoon produces approximately 200 kg/ha/year of fish. However, the shellfish industry is more economically important. Eighteen varieties of shellfish are taken from the lagoon - the most important being

oyster Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not al ...

s. 750 producers farm 2,750 oyster tables and take some 13,000 tonnes annually. This provides for about 8.5% of France's consumption. Oysters from the Étang de Thau are marketed under the name ''huîtres de Bouzigues'' (Bouzigues oysters) after the village of

where oyster production started. They are a cupped variety. Fixed with cement to ropes, the young oysters are immersed in the water until they reach a size suitable for consumption. Thau water is graded A and so shellfish can be caught and consumed within minutes. In addition to oysters, some 3,000 tonnes of mussels are produced every year. Apart from fishing and shellfish, the Étang de Thau provides income through tourism, particularly via sailing schools.

Wildlife

The Bassin de Thau provides a habitat for a variety of wild animals, notably birds such as

herons The herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 72 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genera ''Botaurus'' and ''Ixobrychus ...

and

pink flamingos ''Pink Flamingos'' is a 1972 American film directed, written, produced, narrated, filmed, and edited by John Waters. It is part of what Waters has labelled the "Trash Trilogy", which also includes ''Female Trouble'' (1974) and ''Desperate Livin ...

and a rich marine fauna, including

bivalves Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bival ...

(oysters and mussels),

jellyfish Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella- ...

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

, and

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

. Periodically in the spring and summer, the Thau Lagoon has algae blooms of Alexandrium catenella which sometimes reach such high levels that it results in contamination of the lagoon's bivalves with algae toxins.

Gallery

File:Étang de Thau, Mèze 07.jpg, Étang de Thau and

from

File:Lido de Thau, Sète cf04.jpg, ''Lido de Thau'' with the Étang de Thau on the left, former

salt evaporation pond A salt evaporation pond is a shallow artificial salt pan designed to extract salts from sea water or other brines. The Salt pans are shallow and large of size because it will be easier for sunlight to travel and reach the sea water. Natural sal ...

s on the right File:Dawn on Sète and the Étang de Thau.jpg, Sète and the Étang de Thau at dawn File:Harbour of Mèze at blue hour 01.jpg, Harbour of Mèze File:Lido de Thau, Sète, Hérault 07.jpg, The Ile de Thau neighbourhood and the Étang de Thau seen from the "Lido de Thau" in

File:Bouzigues Parcs Moules.jpg,

Oyster Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not al ...

production at

File:Canal Midi Onglous.jpg,

joins Étang de Thau in Marseillan File:Leuchtturm Canal du Midi-Etang de Thau-DSC 0262w.jpg, ''Phare des Onglous'' lighthouse at the mouth of Canal du Midi

Notes

External links

Website of panoramic photos of the Thau lagoon and its region

{{DEFAULTSORT:Etang De Thau Thau Thau, Etang de Thau Lagoons of Europe Bodies of water of France Gulf of Lion