Summit pounds on French canals often have tunnels. There’s a good reason for this; it is easier to dig a long tunnel than to bring water to the top of a ridge. In the case of the Marne-Rhine Canal, the nearly five kilometer long Tunnel de Mauvages links the two ends of the waterway’s highest pound. Even with the tunnel, water supply is a challenge; water must be pumped up to the canal’s summit.
Taking Wanderlust through a long tunnel is always stressful. The channel of the Mauvages’ tunnel is 6.7 meters wide, only 2.4 meters wider than Wanderlust’s beam. With the sidewall of the tunnel always close, we went through slowly and carefully. It took us more than an hour and a half to reach the far end.
It used to be that barges were towed through the Tunnel de Mauvages by an electric tug. Traffic has dropped and nowadays barges go through under their own power accompanied by a VNF agent on a bike. On hot days, there are worse jobs than following boats through a tunnel on a bike.
(Wanderlust passed through the Mauvages Tunnel on the 21st of July 2015 before mooring for the night in Void. Void is 20 kilometers and 13 locks from the pontoon in Demange-aux-Eaux.)