Point sources for pesticides include farmyard, pesticide storage facilities, the accidental/unintentional emptying or cleaning of sprayer tanks. They can also occur during unwanted applications on farmyards or on impervious surfaces during the preparation of the spayer tanks. They can also happen due to pesticide storage facilities leakage in a farm or in a plant.
An important debate concerns the assessment of the respective shares of water contamination with pesticides due to diffuse pollution and point source pollution. According to the studies, punctual pollution could represent more that 20 % of the total contamination (Müller et al., 2002; Leu et al., 2004), but that share greatly varies with the catchment (20 % to 70 %). Emissions of this type of pollution are generally much more polluting than those produced by diffuse pollution, due to the high concentrations reached in a short time span.