The pollutants can be traced back to wear and tear from drip loss of petrol and motor oil, tyres, road surface, exhaust gas emission, accidents and also the used of road salt.

Refurbishment/Control

Direct discharge of road drainage into the surface water must be avoided. It can be collected in main collectors, treated and then drained away from the catchment area whenever possible.

As a rule, only a few roads should pass through the catchment area if possible. Erection of crash barriers and protection walls in especially dangerous places prevents vehicles falling on to the shore embankment or directly into the water after a crash. Transportation of materials harmful to water is not tolerable, especially in the closer protection areas. There is also the option of reducing the introduction of pollutants into the water by planting the sides of the roads and by looking after them in a way that protects water quality.