ANVÄNDNING AV VÅTMARKER FÖR KOMMUNALT DAG- OCH AVLOPPSVATTEN Nuläge och framtida trender / Use of wetlands for municipal storm- and waste water. Present state and future trends
To treat water of varying quality, composition and origin in constructed wetlands has attracted increased attention in recent years in Sweden. In agricultural districts this interest has been manifested by the creation of wetlands to prevent nutrient leakage, while in urban areas by the establishment of wetlands/ponds to purify and balance storm water flows, or for polishing waste water from treatment plants. Taking as point of departure an earlier study (Söderberg, 1999), telephone interviews were conducted with representatives of mainly technical administrations in 125 Swedish municipalities. The interviews concerned existing wetlands in the municipalities, as well as the municipalities’ future plans concerning wetlands, if any. Two trends were identified: (1) The number of municipalities with wetlands for polishing waste water have increased during the period 1997 to 2000. (2) The number of municipalities with plans for wetlands/ponds for purifying and balancing storm water flows is large compared to the number of municipalities using this kind of wetland todav. The two trends, which are mainly present in urban environments, are presented and discussed. In conjunction with that, future research needs, concerning socio-economical implications that arise with the establishment of open storm water systems in densely populated areas, are identified.