16 August 2023

Cleaner water thanks to Interreg!

Written by Elena Kolosova
Cities and regions share the challenge of the polluted Baltic Sea.  They  have addressed the challenge together taking a long-term perspective. They have worked beyond borders to test and roll out new or adapted solutions to manage wastewater more efficiently. Read about the 25 years of cooperation of cities and regions in Interreg Baltic Sea Region for a cleaner Baltic Sea.
Improving wastewater treatment to reduce eutrophication

The Baltic Sea is one of the most heavily eutrophicated seas in the world. Interreg projects have helped improve wastewater treatment,  one of the factors influencing eutrophication. At the beginning of the 2000s, more than 20 cities collected best practices in water management and shared them with other city administrations around the Baltic Sea region. Such joint capacity-building became a valuable aspect of Interreg, ensuring that no region is left behind in the pursuit of effective solutions to reduce eutrophication and make water cleaner.

Agnieszka Ilola, Deputy Head of the Secretariat of the Union of the Baltic Cities (UBC) Sustainable Cities Commission

“Until today, we’ve benefitted from the Programme in many ways.
Thanks to Interreg funding, we were able to provide our member cities with concrete solutions and tools. We created momentum for essential aspects of sustainable water management connected to climate change, for example improving the wastewater and storm water management, reducing water pollution, and increasing the application of circular economy principles. Although we represent public authorities, we were able to bring in expertise from other organisations, for example, universities, service providers, and the private sector.

It gave us a bigger scope of actions and a slightly different angle for the UBC strategic agenda. Projects have also been essential for awareness raising, peer learning, and knowledge sharing among our member cities.”

Joining forces for more action! 

In 2009-2013, projects showcased that it was possible to reduce discharges of nutrients from wastewater treatment facilities to the level set in the Baltic Sea Action Plan of HELCOM. The HELCOM Action Plan targets were stricter than the EU requirement. Solutions tested in projects brought new evidence for more efficient policy-making in the region.

Dmitry Frank-Kamenetsky, Special Advisor to the Baltic Marine Environment Protection Commission, also known as the Helsinki Commission (HELCOM)

 “We, in HELCOM, largely utilised the results under the Interreg umbrella. First of all, all HELCOM policy decisions have always been based on the best available knowledge. And how the Programme selects projects, how these projects are built from expert groups – or project consortiums as Interreg calls them – it all has provided us with perfect, solid scientific background for respective decisions taken by HELCOM.

I can name a large number of examples of project outputs directly integrated into the regional policy framework. The first one is the recommendation on sludge handling. It was largely based on the PURE project. What’s more, the technologies tested in the project PURE to treat wastewater are in regular use now. Demonstrating to large investors that certain technologies are economically feasible and environmentally efficient is also a very important part of the Programme.”

Rolling out new technologies

In 2016-2021, projects in cities and villages focused on improving the treatment of wastewater from residents and industries. Partners in projects tested new technologies that increased nutrient removal and reduced energy consumption in cities such as Daugavpils, Gdańsk, Tartu, Jūrmala, Kaunas, and Grevesmühlen. Rural municipalities benefitted from solutions like septic tanks and soil infiltration in Kolgaküla, Gennarby, Ainaži, and Leitgiriai. In other projects, partners tested the pre-treatment of wastewater at poultry, meat, and dairy factories in Leszno, Doruchów, Põltsamaa, and Jelgava.

Agnieszka Ilola, UBC Sustainable Cities Commission

“If we didn’t have access to Interreg funding, I think we wouldn’t be able to address so many challenges or at least address them in such depth. We would probably focus more on networking and sharing already existing solutions. I think we wouldn’t be able to mobilise the resources to develop new solutions. Without Interreg, we would miss all the testing, developing together, and learning by doing – also on mistakes. I believe that the process of developing outputs is often more important than the outputs themselves. Interreg also gave our partners a valuable possibility to assess their own processes and think about how they can do their work smarter and better.”

How Interreg projects feed into policy framework

Following this joint work in projects, the partners synthesised more than a hundred examples of smart water operations. Using this knowledge, they helped develop the new Baltic Sea Regional Nutrient Recycling Strategy of HELCOM, and revise the HELCOM Baltic Sea Action Plan. These two strategic documents help achieve a healthy state of the Baltic Sea.

Dmitry Frank-Kamenetsky, HELCOM

“When HELCOM was working on the regional strategy on nutrient recycling, it integrated a synthesis of outputs from several Interreg projects. We cooperated closely with EUSBSR policy area Nutri on making that happen.”


This year, our Interreg Baltic Sea Region Programme is celebrating its 25th anniversary. For more examples of #MadeWithIBSR project results and testimonials of great people who have helped shape the regions with us,  visit our birthday celebrations page!

Want to know more about the projects that have been helping cities and towns become more attractive? Flip through the project examples below:


Better Efficiency for Industrial Sewage Treatment
The project BEST enhanced collaboration among local water utilities, wastewater treatment plants, industrial companies, and local environmental authorities to ensure more efficient management of industrial sewage in the Baltic Sea region and ultimately protect the environment.
Read more about the project


Water emissions and their reduction in village communities – villages in Baltic Sea Region as pilots
The Interreg project Village Waters produced comprehensive knowledge about technical solutions for cleaning waste water in the countryside and successfully made it available to municipal officials, home owners and companies - now they can improve the waste water treatment and comply with EU directives also where large waste water treatment facilities are missing.
Read more about the project


Platform on Integrated Water Cooperation
The Interreg platform BSR WATER filled up the Baltic Smart Water Hub with over a hundred best practices and solutions to clear and smartly manage fresh, sea, storm and waste waters.
Read more about the project


Interactive WAter MAnagement
The Interreg project IWAMA equipped waste water managers with new audit tools and a durable platform for life-long learning and exchange so that they can better protect our environment, in particular by optimising the energy use and sludge management of waste water treatment plants.
Read more about the project

Lakes connect

Building networking hub for units interested in lakes protection in Baltic Sea tourist regions
The project Lakes connect establishes cooperation among authorities, NGOs and researchers in order to reduce the impact of tourism on water quality in lakes.
Read more about the project


Promoting water reuse in the Baltic Sea Region through capacity building at local level
In the project WaterMan, public authorities and water companies model strategies to reuse water and recirculate retained water, e.g. for industry and agriculture.
Read more about the project

R-Mode Baltic 2

Ranging Mode Baltic Sea test bed evaluation
R-Mode Baltic 2 improved the earlier introduced alternative to satellite navigation systems and helped shippers navigate safer in the Baltic Sea.
Read more about the project

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