Except for The Forestay waterfall falling from the same height as Chexbres, the area also includes two rivers at the easterly and westerly corners originating in the back country: “La Veveyse” and “La Lutrive”.
Along the rest of the coast of Lavaux, the short distance between the lake and the ridge (2 to 3 km) and the steep slope have created numerous little slow flowing streams. Depending on the season, these streams either dry out or become gushing rivers during heavy rains as demonstrated by the streams’ names such as “Rio-d’Enfer” (Rio of Hell).
These small streams such as the Châtelard, the Champaflon and the Salenche have nevertheless managed to carve beds deep enough to impact on the land. During the development of the vineyard terraces and continuous landscaping, systems were created to capture the water from the streams in order to prevent soil erosion. Upstream from the terraces’ retaining walls, the waters were collected and diverted into a system of vertical canals. They are then transported through the vineyards to one of the rivers or the lake.
This ancient canal system was completed with subterranean manholes and pipelines set up in paths which enabled motorised vehicles to access and manoeuvre through the vineyards. During heavy rains the paths also reduced the risk of soil erosion as the waters are evacuated to the streams and the lake preventing the canals from flooding. For two decades the vines’ orientation which, in some places, follows the land’s natural contour, has also reduced erosion adding a new element to mankind and nature’s interaction which is constantly evolving.
Source : Bureau GEA Vallotton et Chanard SA, Architectes-urbanistes (Igor REINHARDT, collaborateur), «Hydrologie», in Lavaux, Vignoble en terrasses face au lac et aux Alpes, Lavaux World Heritage Site Application File for UNESCO, Cully, January 2006, pp. 53-56.