The Kamech basin is located north of Cap-Bon, in the governorate of Nabeul, on the border between the sub-humid and semi-arid Mediterranean climates. The average inter-annual rainfall is about 640 mm and the potential evapotranspiration is 1300 mm. The outlet of the basin is occupied by a hilly lake built in 1994 (140,000 m3 of initial capacity). The inter-annual flow coefficient is of the order of 10%-15% and the erosion of 15 t/ha/year. Land use is characterised by a cultivation rate close to 75% with, in order of importance: cereals, legumes and irrigated market gardening. This basin has been the subject of a monitoring of anthropogenic activities (land use and management, agricultural practices...), of agro-climatic variables, and of runoff and erosion since 1994 (+ pesticides more recently) at its outlet and since 2005 on 4 substations. This watershed is part of a network of 27 watersheds monitored under an agreement with the Tunisian Ministry of Agriculture (DGACTA).