The Arguenon (; ) is a French coastal river in the

Côtes-d'Armor The Côtes-d'Armor ( , ; ; , ), formerly known as Côtes-du-Nord until 1990 (, ), is a department in the north of Brittany, in northwestern France. In 2019, it had a population of 600,582.Brittany Brittany ( ) is a peninsula, historical country and cultural area in the north-west of modern France, covering the western part of what was known as Armorica in Roman Gaul. It became an Kingdom of Brittany, independent kingdom and then a Duch ...

region. It flows into the

English Channel The English Channel, also known as the Channel, is an arm of the Atlantic Ocean that separates Southern England from northern France. It links to the southern part of the North Sea by the Strait of Dover at its northeastern end. It is the busi ...

Geography

The length of the watercourse is . The river rises in the commune of Le Gouray in Côtes-d'Armor and flows into the sea near Saint-Jacut-de-la-Mer, in the commune of Créhen, in the Bay of Arguenon. The Arguenon is very wide between Jugon-les-Lacs and Plorec-sur-Arguenon. The Ville-Hatte dam built in 1972 to supply the department with drinking water has created a water reservoir more than long named ''Lac d'Arguenon''. The Arguenon runs northeast from its source to Jugon-les-Lacs, north between Jugon-les-Lacs and Plorec-sur-Arguenon, northeast again between Plorec-sur-Arguenon and Plancoët and north-northeast from Plancoët to its mouth. During high tides a small

tidal bore A tidal bore, often simply given as bore in context, is a tidal phenomenon in which the leading edge of the incoming tide forms a wave (or waves) of water that travels up a river or narrow bay, reversing the direction of the river or bay's cu ...

rises up the river, up to the height of the Guildo bridge.

Communes and cantons crossed

The Arguenon's course is entirely within the

Côtes-d'Armor The Côtes-d'Armor ( , ; ; , ), formerly known as Côtes-du-Nord until 1990 (, ), is a department in the north of Brittany, in northwestern France. In 2019, it had a population of 600,582.Le Gouray (source), Plénée-Jugon, Dolo, Jugon-les-Lacs, Plorec-sur-Arguenon, Plédéliac, Pléven, Bourseul, Pluduno, Plancoët, Saint-Lormel, Créhen and

Saint-Cast-le-Guildo Saint-Cast-le-Guildo (; ; Gallo language, Gallo: ''Saent-Cast-le-Giledo'') is a Communes of France, commune in the Côtes-d'Armor Departments of France, department of Brittany (administrative region), Brittany in northwestern France. It is port c ...

(mouth).

Managing body

The managing body is SAGE Arguenon – Baie de la Fresnaye.

Tributaries

The Arguenon has four named tributary streams, one river and 10 unnamed tributaries including: * Rosette river, , enlarged by the Rieule, . * Bos Robert stream, , in the two municipalities of Langourla and Plénée-Jugon. * Quiloury stream, , in the four municipalities of Le Gouray, Penguily, Plénée-Jugon and Saint-Glen. * Étang du Guillier stream, , over the four municipalities of Jugon-les-Lacs, Plédéliac, Plestan and Tramain. * Montafilan stream, , in the six municipalities of Corseul, Créhen, Plancoët, Plélan-le-Petit, Saint-Maudez and Saint-Michel-de-Plélan. We can also add, according to the National Institute of Geographic and Forest Information or

Géoportail Géoportail is a comprehensive web mapping service of the French government that publishes maps and geophysical aerial photographs from more than 90 sources for France and its territories. The service, first developed by two public agencies (the ...

, and since the Guébriand is not a river in its own right: * The Guébriand, , passing through the commune of Landébia and joining the Arguenon between the communes of Saint-Lormel and

at the entrance to Arguenon bay opposite the town of Créhen.

Hydrology

Arguenon at Jugon-les-Lacs

The Arguenon has been observed in Jugon-les-Lacs since 1972 at station J1103010 L'Arguenon, at an altitude of with a catchment area of . The annual average of its flow at this point is .

Low water

At low water the minimum flow rate of the watercourse recorded for three consecutive days in a month, during a five-year dry period, was .

Floods

During the observation period, the maximum daily flow was observed on 28 February 2010 at . The maximum instantaneous flow (QIX: ''quantité instantanée maximale'') was observed at 14:21 on 28 February 2010 was , and at the same time the instantaneous maximum height was . The 10-year QIX is , the 20-year QIX is and the 50-year QIX is while the 2-year QIX is and the 5-year QIX is . The Arguenon has experienced several significant floods. The first took place in 1974. The water overflowed on the Plancoët quay, causing major and widespread damage. The second took place in 2010, this time with on the quayside. The floodwater affected a lot of businesses. The last took place in February 2014, with on the quays. Shops were closed permanently and a park was completely flooded.

Depth of runoff and specific flow

The depth of runoff in this part of the river's catchment area is annually, which is a little lower than the average in France. The specific flow rate reaches per of basin.

Facilities and ecology

The Arguenon is crossed by Route nationale 176 and Route nationale 12. The Arguenon estuary is protected by a '' Zone naturelle d'intérêt écologique, faunistique et floristique''. Arguenon Bay is part of the

Natura 2000 Natura 2000 is a network of nature protection areas in the territory of the European Union. It is made up of Special Areas of Conservation and Special Protection Areas designated under the Habitats Directive and the Birds Directive, respectiv ...

zone Lancieux Bay, Arguenon Bay, Saint Malo and Dinard Archipelago.

Notes

Citations

Sources

* * * * * * * {{DEFAULTSORT:Arguenon Rivers of Côtes-d'Armor Rivers of Brittany Rivers of France