Auftausalze im Straßenwinterdienst - Aufkommen und Bedeutung für dezentrale Behandlungsanlagen von Verkehrsflächenabflüssen zur Versickerung

In Germany, sodium, calcium and magnesium chloride and their mixtures are used as de-icing salts in winter roads maintenance. With the exception of small municipalities, pre-wetting technologies are used for spreading the salt on the roadway and de-icing salts are usually found in the months of November to April in traffic area runoff waters. Salt concentrations higher than 10 g/L are sometimes measured in traffic area runoff. These concentrations are significantly higher compared with other pollutants and may negatively affect the treatment steps of decentralized stormwater treatment systems for traffic area runoff. A remobilization of pollutants by the use of each de-icing salt is possible. To quantify the risk of remobilization, two laboratory-scale test methods were developed. By these methods, the compliance with legal requirements can be examined during the use of de-icing salts.