Policy recommendations for implementing the integrated stormwater management
Increased occurrences of extreme weather events are one of the most popular aspects of the climate change noticed in the Baltic Sea Region. With the flooding threat being imminent and the adaptation measures urgently needed, how to approach this process holistically? We hope that the publication "Regional and national policy recommendations for implementing the integrated stormwater management in the Baltic Sea Region" will aid cities in this process.
This publication was developed within the platform project BSR WATER as one of its key outputs. The report was prepared by the project partner Riga City Council with support from BSR WATER partners, and it is based on the surveys and interviews with 25 cities from 10 countries around the Baltic Sea. The cities that contributed to the survey – many of those UBC members! – have already obtained experience, understanding and practical skills in the sustainable urban stormwater management and now share their expertise as they continue to develop their systems. Although most of surveyed cities have only implemented their first pilots, a few forerunner cities apply sustainable techniques as a common practice to improve the water and overall urban space quality of the city.
With the conventional practice of conveying stormwater into wastewater or separate sewers, several municipalities indicated they have adopted binding rules and guidelines for stormwater drainage and treatment that include prioritizing infiltration and retention of stormwater at the source, which is important when preparing cities for extreme storm events and mitigating the effects of climate change. Still, in the Baltic Sea Region, not enough attention is paid to promotion of open, nature-based, on-source stormwater drainage and treatment solutions.
At the national level, the explicit requirement for the treatment of stormwater runoff from all surfaces except for natural surfaces should be specified.
The City of Riga is a known forerunner in the stormwater management activities, and it has actively streamed the accumulated knowledge and developed the practices further in the transnational project iWater – Integrated Stormwater Management (ISWM). Within the BSR WATER platform, which unites seven self-standing projects in order to stream their findings and lessons learned into the regional policies level, the cities Riga and Helsinki (another prominent partner in iWater and BSR WATER) continued constructing a clear process for taking up ISWM, seen as one of the core aspects of adapting cities to the climate change.
As defined in the report, contrary to conventional stormwater management practices, ISWM undertakes a comprehensive and holistic approach to stormwater management: studying the characteristics of specific sites and areas, understanding the relevant impacts, and tailoring a comprehensive array of tools to individual situations. Success requires the integration of the ISWM system into the urban development processes of the city at all levels, from urban planning to operation and maintenance.
National level regulation/guidance should encourage (though not mandate) the ISWM at the local level, by specifying involvement of specific stakeholders (entities responsible for urban planning, infrastructure planning, traffic planning, maintenance, water companies etc).
BSR cities that were interviewed on the introduction of sustainable stormwater management approaches and tools, highlighted the importance of this topic in the entire urban planning system – all interviewed cities admitted the need to introduce the ISWM system and adapt sustainable urban stormwater planning principles in the near future.
Local financial incentives to promote the introduction of the ISWM approach and introduce green infrastructure and nature-based solutions are an important tool to support development of natural, holistic, and sustainable stormwater management.
The report presents two sides of the stormwater management implementation in the region: analysis of local stormwater management governance and practices, as well as a compilation of the stormwater management legislation on the local, regional and national level in the inspected cities and countries. The policy recommendations are developed for several levels: EU, Baltic Sea Region, national and local.