The project investigates the effectiveness of the currently used urban runoff solutions on areas characterized by clay soil. The objective is also to develop suitable treatment methods for clay soil areas.

Southwest Finland is a problematic area in terms of controlling urban runoff. The ground is frozen in the winter and the soil is often clay. Part of wintertime rainfall may be rain.  Little research has been conducted on urban runoff solutions suitable for cold clay soil.

The project focuses on the residential area built on an area of clay soil in Rauhalinna, Kaarina. The construction started in 2015 and continues until 2020. The project researches the effects of the urban runoff solutions implemented in the area and of construction on the quality and amount of urban runoff. In addition, the practical functioning of the urban runoff solutions will be mapped. The current urban runoff solutions are further developed and new ones are created in order to find effective solutions with regard to clay soil.

The data gathered during the project can be utilized both in Finland and abroad when urban runoff solutions are needed for clay soil in cold regions.