TheMerwede (Dutch pronunciation:[ˈmɛrʋeːdə]; etymology uncertain, possibly derived from theOld Dutchmerwe ormerowe, a word meaning "wide water") is the name of several connected stretches of river in theNetherlands, between the cities ofWoudrichem,Dordrecht andPapendrecht. The river is part of theRhine–Meuse–Scheldt delta and is mostly fed by the riverRhine.
At first, a disconnected branch of theMeuse joins theWaal atWoudrichem to form theBoven Merwede (Upper Merwede). A few kilometers downstream it splits into theBeneden Merwede (Lower Merwede) on the right and theNieuwe Merwede (New Merwede) on the left. All these rivers are tidal. The Nieuwe Merwede joins theBergse Maas near Lage Zwaluwe to form theHollands Diep estuary, and separates the Island of Dordrecht from theBiesbosch National Park. The Beneden Merwede splits into theNoord River andOude Maas near Papendrecht.
In medieval times the name Merwede (or "Merwe" in Middle Dutch) was the name of a continuous stretch of river, considered to be the lower part of the riverWaal (a major distributary branch of theRhine), and carried on its name all the way to the sea. Later on, the name Merwede was discarded downstream of the town ofPapendrecht and replaced withNoord river and, even further downstream,Nieuwe Maas. Only the part of the river between Woudrichem en Papendrecht retained its name.
The confusing river names are the result of two major flood events, which both resulted in a significant shift in the course and flow of the lower rivers. The first of these events forced the riverMeuse (Maas) to take a more northerly course and created a direct connection between the Meuse and the Merwede at the town of Woudrichem. The names of several stretches of the lower rivers were then changed to reflect this, for example theOude Maas andNieuwe Maas.
During a second flooding event (theSt. Elizabeth floods) a major breach in the coastal dunes ofHolland created an inlet that would eventually reach the Merwede, thus creating a new, more southerly and shorter path to the sea. Most of the flow of the riverMeuse, and a considerable part of the flow of theRhine (by means of theWaal), were rerouted to this new pathway (the currentBiesbosch,Hollands Diep andHaringvliet). From that time on, the Oude Maas and Nieuwe Maas received little water from the Meuse. In recent centuries the influence of the Meuse has decreased even further, to the point that the major stretches of river calledOude Maas andNieuwe Maas have been essentially cut off from the river Meuse completely.
Both the current Merwede and all of its lower stretches (now calledNoord river,Oude Maas andNieuwe Maas) are now consequently almost exclusively fed by the Rhine, while the Meuse has been given its own artificial mouth,Bergse Maas, and the two rivers Rhine and Meuse are now mostly separated to reduce the risk of flooding. This separation of the rivers Rhine and Maas is considered to be the greatest achievement in Dutch hydraulic engineering before the completion of theZuiderzee Works andDelta Works.[1][2]
TheMerovingian dynasty probably derived its name from this river.
