The Boven Merwede river splits at Hardinxveld-Giessendam into the Beneden Merwede river on the right and the Nieuwe Merwede river on the left. It joins the Bergse Maas river near Lage Zwaluwe to form the Hollands Diep. Like the Bergse Maas river, the Nieuwe Merwede (New Merwede) is man-made: it has been formed in 1870.

There are no bridges or tunnels crossing the Nieuwe Merwede, but there is a car ferry from Dordrecht island on the west at "Kop van 't Land" to Brabantse Oever, Werkendam (Biesbosch). [1]

http://www.binnenvaart.be/pictures/kaarten/waterwegen/22maasmond.gif