Hydraulique agricole et aménagement des rivières

Drainage and irrigation act on transfers between soils and ground water. They have a direct influence, therefore, on rivers both as regards the hydrological regime and the quality of the water.At present there are methods allowing for the minimization of high water levels from drainage networks. These waters thus transferred can be charged with fertilizer substances, mainly nitrates and also pesticides. An improvement in growing methods enables these risks to be minimized.Irrigation uses large quantities of water. The installation of connectors, canals, basins, dams comes up against difficulties and may lead to major modifications in the water-flow regime.The implementation and management of these developments requires more studies and precautions than in the past. The effect on underground water must be taken into account.Drainage and irrigation increase greatly the productivity and adaptability of agriculture. Now a more refined agriculture enables the quality and the good state of the hydrographic network to be guaranteed at the same time.