The main crop is the vine. The site is strongly anthropised (network of ditches, terraced slopes, etc.). The climate is sub-humid Mediterranean with a prolonged dry season. The average annual rainfall is around 650 mm and the average annual ETP (Penman) is 1090 mm. The basic hydro-meteorological equipment, in place since May 1992, consists of a network of 9 rain gauges and 4 pluviographs, a device for measuring water table heights (14 sites), a device for measuring flows, suspended matter and pesticides at the outlets of the catchment area and of two plots with different cultivation routes and a network of 8 stations for measuring soil water content and water potential. Roujan was part of the reference catchment area network of the Network Observation Service Used for Hydrology Research created by the GIP Hydrosystème.