The pollution with phosphorus: a barrier for the improvement of an ecological state of the rivers in the Upper Silesia

In the paper, the problem of pollution of rivers with phosphorus in highly urbanised part of the Silesia Voivodeship has been analysed. There has been stated that despite the considerable development and modernisation of the municipal sewage treatment systems, significant improvement of the water quality has not occurred in the last ten years and the total phosphorus concentration exceeds several times the threshold values that limit the possibility of achieving a good ecological state, as defined by the Framework Water Directive. There has been formulated a hypothesis according to which considerable improvement is likely to be achieved, on condition that there would be introduced the sewage additional cleaning systems as well as technical and spatial solutions in particular local drainage areas that limit the pollution with phosphorus through the surface run-off from the urbanised areas.