Project description

The Baltic sea is surrounded by a large drainage area where many anthropological activities lead to nutrients and pollutants ending up in the marine environment. Even though significant efforts have been made to address the largest point sources of pollutants from industrial and agricultural wastewater, the stormwater pollutants and the flow of hazardous substances into the Baltic Sea is still not fully solved. The stormwater treatment solutions and their effectiveness has not yet been measured and there is a knowledge gap between the municipalities around the Baltic Sea.

During the Interreg CB CleanStormWater project pilot sites were be constructed in several locations around the Baltic sea to gain data and knowledge in how to efficiently manage stormwater from urban areas. Methods for real time monitoring of stormwater quantity and quality were also be developed during the project.

The main objective of the Interreg CB CleanStormWater project was to:

  • Design and model technological solutions

  • Assessment of stormwater management solution effectiveness

  • E-monitoring systems for real time water quality management

  • Centralised stormwater solutions

  • Decentralised stormwater solutions

Achieved outcomes by the end of Project:

CSW project produced a set of valuable achievements:

  • New pilots of stormwater treatment solutions – Project Partners developed and tested new stormwater treatment solutions to clean stormwater, ensure management quality and monitor water quality in near real time.
  1. comprehensive multistage stormwater treatment system together with real time water quality e-monitoring in Viimsi, Estonia;
  2. advanced vortex separator – a stand-alone application to remove total suspended solids, floatable trash, oil products and other pollutants from the stormwater collected from heavily used, often congested transport infrastructure with e-monitoring in Lucavsala island in Riga, Latvia;
  3. bioretention cells with e-monitoring treating stormwater originating from traffic area in Turku and Avanti industrial area in Lieto, Finland.
  • New guidelines for management of nature-based stormwater solutions (management quality system) – Project Partners jointly produced the new guidelines on how to manage nature-based stormwater structures, from planning phase until monitoring and maintenance phase. They are based on the in-depth analysis of existing literature, a survey among local governments and consultants of stormwater management in Estonia, Latvia, Finland and Sweden, and then practically tested while piloting new stormwater treatment solutions by Project Partners.


The total cost of Project is 1 661 825,73 euros, incl. ERDF support 1 345 373,42 euros and Project Partners´ self-contribution of EUR 316 452,31 euros.