Coastal Reed Project

The objective of the Coastal Reed Project is to recycle the nutrients of reed growths from eutrophicated coastal waters to land. At the same time, we can promote the sustainable and diverse utilization of the reed mass as a raw material that replaces peat, and protect the versatility of nature in a coastal habitat that is threatened by overgrowth.

To recycle the nutrients of reed growths from eutrophicated coastal waters to land.
The work was piloted in the autumn of 2020. Activities will be expanded in 2021 on the basis of experience gained from the pilot phase.

The project was launched in August 2020 with a joint pilot of the John Nurminen Foundation and the Metsähallitus Parks and Wildlife unit, focusing on the maintenance and care of the nature reserves on the coast of the Gulf of Finland. Based on experiences from the pilot, plans are to expand the operations in the coming years.

The common reed (Phragmites australis) is a common, perennial grass that grows in shallow waters, on coastlines, and in wetlands. The reed can grow into thick growths that are 1-3 metres tall and can cover hundreds of hectares. According to estimates, there are tens of thousands of hectares of reed growths on the coast of Finland that would be ready for mowing. Nutrient loads from catchment areas and the decrease in grazing in coastline meadows have accelerated the spread of reed growths, and the overgrowth of the seaside. A thick reed growth will retain significant volumes of nutrients that cause eutrophication in the Baltic Sea. A one hectare reed growth can contain 10 kg of phosphorus, 100 kg of nitrogen, and more than 2 tonnes of carbon.

When the reeds are mowed and the reed mass utilized in the manufacture of e.g. growing substrates, green manure, and drying agents, large amounts of nutrients can be cost-efficiently removed from the coastal waters. When impenetrable reed thickets are opened up, this also adds to the recreational use options of the coastline, and brings back already lost heritage landscapes. Reed growth mowing is planned and implemented so that species that are specialised in reed environments do not lose their habitats.

Reed mass utilization has positive outcomes for the climate, as it can replace peat, which generates heavy carbon emissions, and rock wool, which is manufactured from non-renewable raw materials. Moreover, when reed growths are removed, this slows down the release of methane, a gas that accelerates climate change, from the reed mass rotting in the coastal waters.

We have for quite some time known of the benefits of reed mowing, but activities have so far been project-based and rather small in scale. The key bottlenecks that prevent reed mowing involve harvesting technologies and logistics.  The objective of the Coastal Reed Project is to accelerate the utilization and further processing of the reed mass; to boost harvesting entrepreneurship; and to build business models in a way that will allow us to utilize reeds sustainably and in a market-driven manner.

More information:

Eeva Tähtikarhu
Project Manager, Clean Baltic Sea projects
John Nurminen Foundation
+358 (0)50 314 2102