Non-point source pollution of water is a diffuse form of degradation produced by erosion of land that causes sedimentation of streams, euthrophication from nutrients and pesticides used in agricultural and silvicultural practices and fallout of pollutants from atmospheric sources, for example acid rain resulting from burning fuels that contain sulphur.
This strategy features in the framework of Agenda 21 as formulated at UNCED (Rio de Janeiro, 1992), now coordinated by the United Nations Commission on Sustainable Development and implemented through national and local authorities. Agenda 21 recommends adopting new initiatives at national, subregional and regional levels for controlling the input of non-point source pollutants. This would require broad changes in sewage and waste management, agricultural practices, mining, construction and transportation.