Front page
Details about the project
News section
Description of the different locations
A review of the treatment technologies
Details about the scientific investigations
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With respect to pollutant loads from households and industries, efficient technologies for wastewater treatment are well-established. What remains is reducing the pollutant loads to surface waters originating from urban atmospheric fallout, traffic and urban constructions and installations. In European urban areas, typically 40-60% of phosphorus as the major eutrophying element and of toxic substances (heavy metals and organic micropollutants) originate today from these sources. Methods applied in this project will reduce the total amount of these and other pollutants in rainwater running off from urban areas and roads with 80-95%, thereby being a novel, efficient technology that fulfils requirements from national authorities according to the EC Water Framework Directive and meets the targets of the Sixth Environment Action Plan.

Actions and means involved The project implements and demonstrates facilities for pollutant removal in stormwater flows in 3 different urban areas located in Denmark. State-of-the-art systems (e.g. wet detention ponds) for management of stormwater prior to discharge into streams, lakes and marine waters, to some extent remove particulate bound pollutants. With the novel concept demonstrated in this project, such systems are further developed and extended with filtration and absorption units to remove small particles and the colloidal and soluble bound pollutants. It is considered essential that the treatment facilities are constructed as natural and recreational elements on the form of semi-natural lakes that in a positive way contributes to an improved urban environment.

Expected results The main result of the project is the demonstration and verification of treatment facilities obtaining very high pollutant removal in urban stormwater and road runoff. Although the pollutants in general occur in a rather diluted state, efficiencies between 80% and 95% are expected for phosphorus, heavy metals and a wide range of organic micropollutants (e.g. aromatic hydrocarbons, phenols, PAHs, herbicides and pesticides). The project demonstrates how stormwater in the future can be treated and discharged to sensitive waters without causing ecological and recreational deterioration. It is demonstrated that the simple and cheap treatment concept of a semi-natural lake extended with filtration and absorption is robust, and even for large storms following long droughts excellent treatment performance is maintained.

In Danish