Project Mainstream – Making water conservation easy for forest owners

More information:

Tarja Anttila
Specialist/ Tapio
tarja.anttila@tapio.fi
+358 29 432 6014

Commercial forestry’s strain on the water system is difficult to manage

Finland holds an unofficial world record: we have dug a record number of mire ditches. From the 1950s–1970s, there was high demand in Finland to increase wood production and ditches were dug to allow trees to grow in the drained mires.

According to current information, the impact of drainage ditches on nutrient and solid matter loads and on climate-warming greenhouse gas emissions is destructive. Nutrients that travel with the drained water cause eutrophication in local lakes and the Baltic Sea. The humus, meanwhile, causes the waterways to turn brown.

The strain on the water system is permanently higher in drained areas than in natural mires. Drainage also changes the species composition in mire areas, as species that live in wet environments, like sedges and peat moss, are replaced with species that live in drier conditions.

Diffuse loading accumulates across wide areas over a long period of time. In order to sufficiently reduce the strain on the system, we must first identify the sources of the load by investigating the entire catchment area. Once the major sources of the strain have been identified, we can then target them with the most effective water conservation measures.

Commercial forestry does not currently utilise the most effective water conservation methods, such as the restoration of drained areas that are not profitable for wood production to their natural state, and the rewetting of mires through overland flow. Both measures improve the state of the water system and nature in mire areas.

Putting words into action: practical water conservation methods

The Mainstream project is planning and implementing 15 water conservation areas in Kanta-Häme, in the catchment areas of Lake Kuivajärvi in Tammela and Lake Renkajärvi. These are part of the Kokemäenjoki water system, which discharges into the Bothnian Sea.

Key sources of load are identified through catchment area planning, and the water conservation measures to be implemented will be agreed upon with landowners. More detailed implementation plans will be drawn up for these sites.

Sites especially suitable for restoration are low-productivity forest and non-productive land where tree growth has not recovered despite drainage. Restoration to a natural state will therefore have no adverse economic impact on landowners. Drainage water from commercial forestry ditches will be conveyed for treatment at overland flow fields, which are natural or restored mires.

The John Nurminen Foundation and Tapio Palvelut Oy will implement the project. The Foundation will implement water conservation sites, and Tapio will be responsible for catchment area and implementation planning, for charting the financing options available to forest owners, and for training.

More advice and support for forest owners

Restoration and water conveyance for overland flow is currently carried out within the framework of various projects. Measures should be used more widely than they currently are. In order for this to happen, we need services aimed at forest owners to identify sites and implement these measures on their land. Mainstreaming therefore requires a functional advice system (forestry associations, other service providers) and a functional financing system for implementing measures.

The Mainstream project promotes the mainstreaming of the most effective water conservation methods in commercial forestry by supporting the development of forestry professionals’ competence (catchment area and restoration planning) and by testing the functionality of existing support instruments and providing feedback on their development. Additionally, the project examines the suitability of new financing models based on private funding and communicates opportunities for support and financing.

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