The Beneden-Merwede is a 14.8-kilometer stretch of river in the Netherlands, flowing from Hardinxveld-Giessendam westward to Dordrecht, where it divides into the Noord and Oude Maas rivers. It forms the continuation of the Boven-Merwede downstream of the point where the Nieuwe Merwede ship canal branches off, and is fed primarily by the Rhine.

Paddlers should be aware that the Beneden-Merwede carries significant commercial traffic, as it forms part of the main shipping route connecting the port of Rotterdam with the industrial Ruhr region of Germany. This means the river sees heavy barge and vessel traffic, which generates substantial wash and wake. Paddlers must exercise considerable caution and maintain awareness of large vessels at all times.

Two fixed crossings span the river: a road bridge and, further to the east, a railroad bridge on the Dordrecht–Gorinchem rail line, connecting the railway stations at Dordrecht Stadspolders and Hardinxveld-Giessendam. These structures serve as navigational landmarks along the route.

The river sits within the Rhine–Meuse–Scheldt Delta, a geographically complex region of interconnected waterways in the southwestern Netherlands. The towns of Hardinxveld-Giessendam and Dordrecht anchor the eastern and western ends of the river respectively, with Dordrecht being a historically significant city in the region.

Given the intensity of commercial shipping on this waterway, the Beneden-Merwede is a challenging environment for paddlers and is best approached by those with experience on busy, open rivers. The combination of strong currents typical of Rhine-fed waterways and continuous vessel traffic makes this a route requiring careful planning and sound river-reading skills.