Retentionsräume mit nachgeschalteter Filtereinheit - ein Ersatz für Bodenfilter?

The soil filters installed in NRW serve for local rainwater and mixed water treatment. The BWK-M 3 guideline stipulates the appropriate retention of pollutants in relation to the emissions associated with the discharge of oxygen-depleting substances. Due to the disadvantages of soil filters, such as cost and clogging, there is consideration of a more efficient alternative. A conventional retention basin with a downstream filtration unit functioning as a throttling device could be a viable option. Reactive zeolite mineral could be used for this purpose. Zeolite can only remove cations from mixed and rainwater; a zeolite substrate must be investigated for the retention of oxygen-depleting organic substances. On this substrate, with the addition of sand and organic soil material, the growth of a biological lawn is possible.