The Baixo Alentejo/Mértola, where Vale de Camelos is located, has annual rainfall of 200-600mm (compared to the Bordeaux 984mm region). Regularly, in the heat months of June to September, there is complete dryness with temperatures around 40°C.
The otherwise unused winter rainwater is now collected in five reservoirs that have been built in recent years. It is used to irrigate olives and wine during the dry seasons.
The water areas also form rich biotopes in the otherwise completely dried-up surrounding area. There is no groundwater that could perform this function.