Reducing nutrient inflows into the Baltic Sea

Pilot watersheds as a practical tool to reduce the harmful inflows into the Baltic Sea (Acronym – WATERCHAIN) CB50

It is no secret that the Baltic Sea is one of the world’s most threatened marine ecosystems. In several decades it has accumulated an enormous amount of nutrients and hazardous substances, that inflow from land-based sources, such as agricultural lands, various production sites and private farms. The nutrients and hazardous substances originate from these land-based sources and flow through water bodies until they reach the sea. This accumulation of inflows distorts the functioning of the ecosystem, increases threats to biodiversity and reduces the quality of life and well-being for people living in the Baltic Sea countries.

Landsat satellite image showing the nutrient flows from the mouth of the Daugava River into the Gulf of Riga, Baltic Sea. Image: NASA

Landsat satellite image showing the nutrient flows from the mouth of the Daugava River into the Gulf of Riga, Baltic Sea. Image: NASA

Reducing nutrient and hazardous substance flows to the Baltic Sea region is a complex task, which requires a grassroot level approach. To promote the cleaner future of the Baltic Sea, the project, which is funded by the European Union’s European Regional Development fund and co-funded by the Ministry of Environmental Protection and Regional Development of the Republic of Latvia, will help to reduce nutrients and hazardous substance outflows to the Baltic Sea and reduce the amount of harmful substances already present in pilot watersheds. 


Project Objective

To reduce nutrients and hazardous substances inflows as well as their sources to the Baltic Sea from all types of land-based sources using pilot watersheds as practical tool and using best available environmental technology in most cost efficient way.


Project Activities

The project partners will implement the following activities:

Assessment and reduction of inflowing nutrients and hazardous substances into the Baltic Sea:

  • Collection of existing information and detailed mapping of the sources of pollution;
  • Survey on pilot sites with the local actors on hot spots on pollution;
  • Benchmarking of cost effective prevention methods and environmental treatment technologies for nutrients and hazardous substances;
  • Choosing specific sites, installation and implementation of pilot investments;
  • Water quality studies – sampling and chemical analysis;
  • Implementation of treatment of technologies for nutrients and hazardous substances;
  • Validation of technologies for nutrient and hazardous substances removal.

Project communication:

  • Development of project webpages;
  • Social media communication;
  • Traditional media communication;
  • Seminars for authorities, municipalities, development organisations, NGO’s in Central Baltic region, as well as other countries around the Baltic Sea;
  • Publications of project messages and results – news articles, newsletters, leaflets, interactive cross-border handbook with best practices;
  • Dissemination of project messages and results via digital communication – videos on project activities, online course on lessons learnt.


Our Role

Integrating traditional aquatic science methods with modern remote sensing Earth observation, the multidisciplinary IES’s researchers will carry out a comprehensive study on the pilot areas in Latvia. Currently there is a lack of comprehensive scientific information concerning the ecological functioning and nutrient content in the chosen pilot watershed – river Daugava. Therefore, IES will identify and fill the knowledge gaps on the nutrient concentration and spatial distribution which will be followed by developing nutrient reduction strategies in cooperation with Riga Technical University. As a part of this process IES is planning to use its expertise in satellite remote sensing and acquire data by using state-of-the-art surveillance and environmental monitoring technologies to identify chlorophyll hotspots within the pilot territory which would indicate high nutrient concentrations in waterbodies.



The project aims to develop a best practice that could be applied throughout the Baltic Sea region as a basis of sustainable development. It is expected that by 2023 outflow of nutrients and hazardous substances from pilot watersheds flowing into the Baltic Sea will be reduced. Thus, the project results will have a direct positive impact on the quality of life for people living in the vicinity of the Baltic Sea.


Project Duration: 10.2015. – 09.2018.

Project Manager: Dr. Merja Ahonen, Satakunta University of Applied Sciences, e-mail: , tel. 358 44 710 3061

IES Project Scientific Coordinator: Dr. Matīss Žagars, e-mail:, tel. +371 29218057

IES Project Administrative Coordinator: Roberts Rotbergs, e-mail:, tel. +371 26392616

Funded by: ERDF Central Baltic Interreg IV a Programme 2014 – 2020, 2 029 057 EUR

Co-funded by: Ministry of Environmental Protection and Regional Development of the Republic of Latvia, 13 770 EUR


Leading partner: Satakunta University of Applied Sciences

Partners: Institute for Environmental Solutions, Pyhäjärvi Institute, Turku University of Applied Sciences, KTH Royal Institute of Technology, Tallinn University of Technology, Estonian Environmental Research Centre, Riga Technical University, Åland Waterwork Ltd.


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