Emerging contaminants (EmCons), such as pharmaceuticals, pesticides and industrial chemicals are frequently detected in urban water systems. This project focuses on diffuse washoff of pesticides and their metabolites from hard surfaces and more specifically of glyphosate and its metabolite AMPA. An analysis has been made of recent data regarding washoff of glyphosate and AMPA in a residential area in relation to the use that was reported by the residents in a consistent survey of 100 households. A spatially explicit runoff model for urban areas WETSPA-PST is developed. The model is refined and evaluated for specific processes regarding washoff of sorbing pesticides and their metabolites.