Seabased Measures in Baltic Sea Nutrient Management

P2 Sustainable use of common resources

2.4. Reduced nutrients, hazardous substances and toxins inflow into the Baltic Sea

Central Baltic

01.03.2018 - 31.05.2021

€2 660 550

€1 995 413

Project Summary:

Although nutrient load from land-based sources to the sea has been reduced significantly over the years, good ecological status has not been reached partly due to the large amount of internal loading from the bottom sediments. Moreover, fulfilling the nutrient reductions agreed in the HELCOM BSAP seems challenging for many countries such as Sweden and Finland. Therefore, both Finnish and Swedish governments have decided to include seabased measures in their Baltic Sea protection policy (MSFD and governmental programs). As local authorities are currently also lacking effective means to improve water quality in coastal and semi-enclosed sea areas where the traditional land-based measures are not sufficient, there is a growing demand for applying seabased measures. Scientists have proposed various seabased measures for the Baltic Sea. However, comprehensive information with regards impacts, costs, risks, applicability and financing of the different measures is currently lacking.

The project aims at reducing nutrients from the Baltic Sea and at improving water quality, especially in coastal areas, by piloting and developing seabased activities. As an added benefit, some of these measures enable nutrient recycling and circular economy.
The project will pilot several promising measures, such as 1) recycling nutrients from bottom sediments or nutrient-rich bottom waters for further use on land, 2) recycling nutrients on land in the form of fish such as stickleback, 3) applying various nutrient binding materials to sediments. Moreover, the project aims at facilitating an open, multi-disciplinary and cross-sector dialogue on benefits and risks of seabased measures and their applicability in Baltic Sea context.
As a result, the project will develop the concept of Marine Habitat Bank for local water quality improvement and ecosystem restoration measures; and Practical Guidelines on Seabased measures in the Baltic Sea.

Lead Partner

John Nurmisen Säätiö

Country: FI

Partner budget: 737.055 EUR

Amount of ERDF funding: 552.791 EUR ERDF

Project Partners

Varsinais-Suomen ELY-keskus

Country: FI

Partner budget: 470.510 EUR

Amount of ERDF funding: 352.883 EUR ERDF

Ålands fiskodlarförening r.f.

Country: FI

Partner budget: 117.501 EUR

Amount of ERDF funding: 88.125 EUR ERDF

Ålands Landskapsregering

Country: FI

Partner budget: 359.985 EUR

Amount of ERDF funding: 269.989 EUR ERDF

BWC Sweden Ekonomisk Förening

Country: SE

Partner budget: 0 EUR

Amount of ERDF funding: 0 EUR ERDF

Stockholms Universitet

Country: SE

Partner budget: 496.364 EUR

Amount of ERDF funding: 372.273 EUR ERDF

Länsstyrelsen Östergötland

Country: SE

Partner budget: 479.136 EUR

Amount of ERDF funding: 359.352 EUR ERDF

Associated Partners

Ålands fiskare r.f.

Country: FI

Lokalkraft Leader Åland

Country: FI

Länsstyrelsen Stockholm Enheten för miljöanalys och miljöplanering

Country: SE


Country: EE

BWC Sweden Ekonomisk Förening

Country: SE

Expected results

The main results of the Project will be:
1) Guidelines on seabased measures to act as a practical “handbook” for authorities and policymakers in assessing, selecting and discussing the possibilities of applying sea-based measures in water protection policy in the BSR. Assessment of the feasibility of identified seabased measures for removing nutrients from the Baltic Sea from the point of view of their environmental, financial and social sustainability will be included. In addition, Plans for commercialization and financing of seabased measures will be included, to enable proceeding from project based approach into sustainable long-term financing scheme.
2) A sustainable concept for verified measures which remove nutrients, improve coastal water quality and restore coastal ecosystems to enable ecological compensations in marine environment. The concept can have a multitude of application areas within the Baltic Sea revival in the future.
3) Cross-sectoral discussion on the seabased measures within and between countries for integrating the measures into environmental policies.
4) Concrete removal of approx. 10 t phosphorus (P) from marine environment by 2 sediment removal and 2 nutrient rich water removal pilots. A future potential of several hundred tons of P are targeted with further implementation of the piloted measures.
5) Pilot area restoration to achieve better ecological condition by marl application at 3 pilot sites and harvesting dense population of stickleback fish in two coastal bays. Both of the measures can potentially be utilized further as verified measures for ecosystem based compensations.
The project links to the result indicator by:
1) Implementing 10 pilots, which reduce up to 10 t P and/or restore pilot areas towards better environmental status.
2) Introducing a concept for implementing effective sea-based nutrient reduction measures in the future.
3) Providing guidelines for including sea-based measures in Baltic Sea protection policy.

Internet presence

Project website

Lead Partner website with project information in three languages

Lead Partner Facebook


Seabased YouTube videos

Other media visibility

Itämeren sisäiseen ravinnekuormitukseen ei ole ihmelääkettä (2021)

Key conclusion from the SEABASED project: no silver bullet for reducing internal nutrient load (2021)

Bräckt vatten kan hjälpa skörden under torra somrar (2021)

Helikopterista levitetään tonneittain fosforia sitovaa kalkki­kiveä – uutta menetelmää Itämeren elvyttämiseksi... (2020)

Slut på blågrönalger? Helikopter spred kalksten ... i Nådendal i nytt projekt som ska rädda Östersjön från övergödning (2020)

Muddring av havsbotten för dyrt – men sedimentexperimenten utanför Houtskär fortsätter (2020)

Kalk är ännu inte ett alternativ på Åland (2020)

Persistence needed in Baltic Sea protection (2019)

Fosfor och kväve ur havet ska bli gödsel på vallarna (2019)

Hållbart fiske bidrar till att rädda Östersjön (2019)

Projektet Seabased ska minska övergödningen (2018)

Seabased tutkii meren ravinnekuorman poistamista - Pilotointi alkaa Itämerellä (2018)

Finding the right methods of fishing stickleback - Blog October 2020

Stakeholders’ views on sea-based measures: Need for long-term studies and pilots - Blog September 2020

Gäddfabriker kan minimera eutrofieringens biverkningar - Blogg 2020

Cornerstones for building a compensation concept - Blog 2020

First trial with a new phosphorus sequestering agent in the Stockholm archipelago - Blog 2020

Pike factories reduce the adverse effects of eutrophication - Blog 2020

Sweet results after a salty summer - Blog 2020

Project videos

SEABASED-hanke: Kolkanlahden kalkkikivipilotti. Milloin tuloksia? Miten kalkkikivi toimii? (2020)
Nutrients to field (2020)
Artificial reefs in the Project SEABASED (2020)
SEABASED-hankkeessa tehdään keinoriuttoja kaloille Itä-Götanmaalla (2020)
Applying treated marl into the bay in Kyrksviken - a pilot in the SEABASED project. (2020)
Project SEABASED - Irrigating with nutrient-rich waters in Kaldersfjärden (2019)
Spiggfiske (2019)