The information on the significance of wetlands in water protection (reducing nutrients) is based on results received from a few large sites.  The water-protection significance of small and non-maintained wetlands, however, has been studied very little. Nevertheless, it is important to find out the importance of undersized wetlands, as a great number of them have been built in the Finnish countryside.

The project also examines the effect of maintenance on the efficiency of the wetlands’ functions, as maintenance work is often neglected. In addition, the question of whether the natural phosphorus-binding power of the bottom sediment in wetland basins can be enhanced by improving the oxygen situation of the sediment is studied for the first time.

It is often impossible to build full-size solutions, which means that it is necessary to discover and develop alternative measures. Harnessing the natural nutrient-binding ability of the clay material for water conservation is a potential economical and environmentally friendly way of enhancing the water-protection effect of small wetlands and settling basins.