In recent years, research was carried out on pathways of substances dissolved in the agricultural catchments. The proportions in which the total outflow involves the forms of water migration: runoff, subsurface and baseflow are important for translocation of pollutants are. The study showed that the share of individual migration routes in the basin is variable in space and time in agricultural catchment. In the North-Eastern Poland the most intense period of chemical denudation is snowmelt. Therefore, early spring melt is critical for water quality . In addition, part of the outflow of highly contaminated are tile drain outflow in agricultural catchments.