Abstract A small lake close to a main highway in the Oslo area has been studied with regard to water quality. The contribution of pollutants from the surrounding area, from the local atmosphere, and directly from the pavement has been studied and related to the quality of the lake water and the outflowing water. PAH's, heavy metals, and several other quality parameters are evaluated in this respect. Studies of lead, cadmium, zinc, and PAH in sediments and bottom organisms are included. The results indicate that the contribution of micropollutants from the inflowing water is relatively moderate whereas several important pollutants appear to be transported as dust via the atmosphere in considerable concentrations, appearing for instance in the snow on the ice during the winter.