In the ancient port of Arles on the Rhône, in 2014, French researchers made an astonishing discovery. They found a Roman water supply network – eight threads of lead pipes laid across the Rhône bed, at a depth of 12 meters. Each section of pipe laid on the bottom is approximately 200 meters long. These sections consist of 3-meter-long sections.
They were hot joined, i.e. soldered. Traces have been preserved that enable the reconstruction of the pipe joining technique. At their ends, craftsmen placed drops of lead in the shape of olives – after heating up, they enabled connecting individual sections.
The technique was so complicated and difficult that the specialists who mastered it put their names near the joints. The individual lines were 50 meters apart. Soldering was done on a steep bank. 200-meter sections lying on the shore along the riverbed were framed in oak protective lagging.
The next operation was relatively easy – pipes lying along the shore in a wooden lagging were rolled into the water. Because they floated, they could be turned across the current with ropes, then lightly weighted down to sink and rest on the bottom. It is not known when this water supply was laid.
