Nervión (; ) is a river that runs through the town of

Bilbao Bilbao is a city in northern Spain, the largest city in the Provinces of Spain, province of Biscay and in the Basque Country (greater region), Basque Country as a whole. It is also the largest city proper in northern Spain. Bilbao is the List o ...

, Spain into the Cantabrian Sea (

Bay of Biscay The Bay of Biscay ( ) is a gulf of the northeast Atlantic Ocean located south of the Celtic Sea. It lies along the western coast of France from Point Penmarc'h to the Spanish border, and along the northern coast of Spain, extending westward ...

). Its lowermost course, downstream of its confluence with the Ibaizabal River, is known as the Estuary of Bilbao.

Geography

The river is long from its source at the

Burgos Burgos () is a city in Spain located in the autonomous community of Castile and León. It is the capital and most populous municipality of the province of Burgos. Burgos is situated in the north of the Iberian Peninsula, on the confluence of th ...

and Alava provincial limits to the sea and runs in a South to North direction. Soon after its source, the river forms a spectacular waterfall in the Delika canyon ( Alava) and then enters the

Biscay Biscay ( ; ; ), is a province of the Basque Country (autonomous community), Basque Autonomous Community, heir of the ancient Lordship of Biscay, lying on the south shore of the Bay of Biscay, eponymous bay. The capital and largest city is Bilb ...

province through the city of Orduña. This waterfall is the largest in Spain with its 222 metres. It re-enters Alava through the towns of

Amurrio Amurrio is a town and Municipalities of Spain, municipality located in the northwest part of the province of Álava, in the Basque Country (autonomous community), Basque Country, northern Spain. It has over 10,000 inhabitants. It is between Vitori ...

and Llodio. The river then runs back into Biscay province and out to the Cantabrian sea, entering the

Bilbao metropolitan area The Bilbao Metropolitan Area (in Basque language, Basque: ''Bilbo Handia'', in Spanish language, Spanish: ''Área metropolitana de Bilbao'') is the metropolitan area or continuous urban area based around the city of Bilbao, in the Basque Country ...

at Ugao-Miraballes. The tidal influence reaches inland from the sea, in Bilbao's old town. The main

tributaries A tributary, or an ''affluent'', is a stream or river that flows into a larger stream ('' main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which the ...

are: * From the west: '' Cadagua'' and ''Galindo''. * From the east: ''Arratia'', '' Ibaizabal'' and ''Asua''. The Ibaizabal is considered by some to be an equally important river, so the whole system is often called Nervión-Ibaizabal and the final tract just "''Estuary of Bilbao''". The basin area is .

Naming

Despite its current popularity in Spanish, the traditional name of the stretch between the estuary and

Basauri Basauri is a major municipality of Biscay, in the Basque Country (autonomous community), Basque Country, an Autonomous Community in northern Spain. The town is a part of the Greater Bilbao conurbation, being only a few kilometers south of Bilbao. ...

, where the Ibaizabal and Nervión merge, is ''Ibaizabal'' (meaning 'wide river' in

Basque Basque may refer to: * Basques, an ethnic group of Spain and France * Basque language, their language Places * Basque Country (greater region), the homeland of the Basque people with parts in both Spain and France * Basque Country (autonomous co ...

), according to historical evidence traced from the eleventh century up to the twentieth. Charles Frederick Henningsen, who travelled across the Basque Country during the

First Carlist War The First Carlist War was a civil war in Spain from 1833 to 1840, the first of three Carlist Wars. It was fought between two factions over the succession to the throne and the nature of the Monarchy of Spain, Spanish monarchy: the conservative a ...

, calls the river in Bilbao the Ibaizabal. The literary writer from

Miguel de Unamuno (1864–1936) as well as former mayor of Bilbao Javier Ybarra (1913–1977) refer to it as the Ibaizabal. Geological and hydrological data also seem to support this assumption.

History and economy

Since ancient times, the Orduña pass that links Spain's inner

plateau In geology and physical geography, a plateau (; ; : plateaus or plateaux), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. ...

with the Nervión valley has had a great economic impact. During the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of global history. It began with the fall of the Western Roman Empire and ...

it served as a natural border between the Biscay lordship and Castile counties, and tolls were collected there. Through the centuries, the Nervión valley was a vital communication corridor for Biscay, and the main rail line from Bilbao to the rest of Spain was constructed following the river in 1870. At the same time, Bilbao developed great commercial activity, with its

seaport A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Hamburg, Manc ...

being the most important on the north coast of Spain. The port's activity relied totally on the navigability of the river in its final . Engineer Evaristo Churruca developed an enormous project that would solve the traditional navigation problems of the river. The estuary divided the population of

Greater Bilbao Greater Bilbao (Basque language, Basque: ''Bilboaldea'', Spanish language, Spanish: ''Gran Bilbao'') is an administrative division of the province of Biscay, in the Basque Country (autonomous community), Basque Country, Spain. It is one of the se ...

; the

Left Bank In geography, a bank is the land alongside a body of water. Different structures are referred to as ''banks'' in different fields of geography. In limnology (the study of inland waters), a stream bank or river bank is the terrain alongsid ...

was occupied by factories (steel, smelting and shipbuilding) and their workers, the

Right Bank In geography, a bank is the land alongside a body of water. Different structures are referred to as ''banks'' in different fields of geography. In limnology (the study of inland waters), a stream bank or river bank is the terrain alongsid ...

was a residential area for the factory owners. Now that the River Nervión has lost economic importance, the navigable part of the river is being abandoned in favour of the sea port, to allow urban development to take place on the banks of the river after the withdrawal of heavy industry. The quality of the water has improved through sanitization projects on the river and the disappearance of the most polluting industries.

Environment

After a century of intense industrial activity the river, especially the final , was ecologically dead with

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

levels 20 percent below the norm. This made the Nervión one of the most polluted rivers in the world. In 1990 the local authorities launched a plan to overcome this situation, resulting in a constant improvement of the environmental status that after 15 years has transformed the Nervión in to a clean river, full of aquatic life.

References

External links