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Reducing summer tourism’s impact on Baltic Sea coastal wastewater plants

As summer graces the Baltic Sea region, many individuals eagerly embark on their well-deserved holidays, flocking to coastal summerhousesguesthouses and resorts. While this brings joy and relaxation, it also poses new challenges for the Baltic Sea’s ecosystem. The surge in tourism leads to seasonal fluctuations in wastewater generation, overwhelming the coastal wastewater treatment systems during the summer season.  

Johanna Lehtmets, Anette Parksepp / Published on 3 July 2023

The sandy beaches of the Baltic Sea are popular among tourists during the summer months. Photo: Franz-Marc Frei / Getty Images.

Small towns and villages surrounding the Baltic Sea have experienced a surge as tourist destinations, particularly following the Covid-19 pandemic. The peak tourism season aligns with the summer months, attracting a larger influx of people to coastal regions and their establishments. However, the existing wastewater treatment systems have been designed to accommodate the average population throughout the year, rendering them inadequate during the summer months. This creates a range of problemsincluding unpleasant odours, overwhelmed municipal wastewater treatment plants and further contamination of the already fragile Baltic Sea ecosystem. 

Introducing the NURSECOAST-II project 

In response to these challenges, the new international project NURSECOAST-II has been established, in which SEI is a proud member. This project aims to enhance the health of the Baltic Sea by improving the resilience of small wastewater systems that are particularly vulnerable to high seasonality. While Estonia has directed substantial investments towards large wastewater treatment plants with a capacity exceeding 2000-person equivalent (PE), less attention has been given to small-scale wastewater treatment plants (50-1999 PE) and individual wastewater plants (< 50 PE). In the NURSECOAST-II project, SEI Tallinn is specifically investigating individual wastewater systems in Saaremaa municipality that are linked to tourism facilities.  

Experts from the project will contact owners of individual wastewater plants in Saaremaa municipality in early autumn. They will be asked to fill out a questionnaire to evaluate the condition and functionality of the wastewater treatment plants on-site. This assessment will provide valuable insights into the current situation and help determine the necessary investments for system upgrades and their most efficient implementation.  

The findings of this study will contribute to the development of a comprehensive database that Saaremaa municipality can utilize to improve wastewater treatment practices. Given that Saaremaa hosts over 130 small wastewater treatment systems related to tourism, these insights will play a vital role in fostering compliant and sustainable wastewater management in the region. 

The NURSECOAST-II project recently kicked off in Barösund, an archipelago town in Inkoo, southern Finland. This location exemplifies the wastewater challenges associated with seasonal tourism. Each year, the retreat of the winter ice heralds the tourism season, attracting an additional 4000 individuals to the village and generating 12 times more wastewater compared to the winter period. Inkoo Municipality is actively exploring appropriate solutionsincluding affordable and suitable wastewater treatment technologies that can accommodate the fluctuations in wastewater volume. Factors such as separating greywater and finding suitable canalization options within the rocky terrain are being considered. The project will address similar challenges across its pilot locations in Finland, Denmark, Latvia and Poland. 

NURSECOAST-II kick-off in coastal touristic village Barösund, Finland. Photo: Anette Parksepp/SEI Tallinn

Over the next two and half years, the NURSECOAST-II project will pilot various approaches, including innovative wastewater treatment technologies, treated wastewater reuse, nature-based solutions and effective management of greywater and sludge. The project will also conduct exploratory surveys to gain deeper insights into operational problems associated with small-scale wastewater systems.  The outcomes will pave the way for informative tutorials, policy guidelines and incentives for the business sector, all aimed at enhancing wastewater treatment practices in Baltic Sea tourism destinations.  

SEI Tallinn´s senior expert Tiia Pedusaar presenting at NURSECOAST-II kick-off meeting. Photo: Anette Parksepp/SEI Tallinn

Watch the video below to hear more about the aims of the project and its planned activities from Ksawery Kuligowski, the project manager from the Institute of Fluid-Flow Machinery Polish Academy of Sciences:  

Discover the latest news, track progress and delve deeper into the project activities by visiting the dedicated website.


SEI people

Johanna Lehtmets

Communications Manager


SEI Tallinn

Anette Parksepp

Communications Expert


SEI Tallinn

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