There was a strong deterioration in the water quality of the River Maas last year according to a new report from Belgian and Dutch water companies. More toxic substances were discharged into the waterway and as a result of climate change the river is running dry in more and more places. As a result toxic substances are being diluted to a lesser extent. Last year seventy-nine substances were measured in concentrations above the European norm. The River Maas is responsible for 40% of Flemish drinking water. The companies say it will become increasingly difficult to supply drinking water of a high quality from the Maas.