Peatland restoration in Finland could provide an additional benefit for territorial defence by making parts of the country harder to cross with heavy military vehicles. A working group led by the Ministry of the Environment (Ympäristöministeriö) and the Ministry of Defence (Puolustusministeriö) estimates that at least 180,000 hectares of mires in eastern and northern Finland could be restored in areas where wetter terrain would also support national defence.
The primary purpose of restoration remains environmental. It is intended to improve biodiversity, restore damaged ecosystems and strengthen adaptation to climate change. But the Finnish government is now considering whether some of the same measures can also create natural obstacles to movement.
Finland sees defence potential in peatland restoration
The joint ministerial working group, which published its conclusions in June, found what it described as significant synergies between habitat restoration and national defence.
The potential is particularly relevant in eastern and northern Finland. Restoring drained mires or former peat-production areas raises water levels and makes the terrain wetter, which can make it more difficult for heavy vehicles to cross.
The group estimates that at least 180,000 hectares of Finnish peatland could be restored in places where this would also have a defence benefit. It identified particularly strong potential on state-owned land, while measures on private property should remain voluntary.
According to Yle, restoring one hectare would cost an average of about €1,000. Applied mechanically to the entire 180,000-hectare estimate, that would correspond to around €180 million, although the figure does not represent an approved national programme or budget.
The working group’s proposal is therefore not to restore peatlands primarily as military infrastructure. Instead, it identifies areas where projects already serving environmental objectives could simultaneously make the landscape less accessible to military vehicles.
Twenty years of restoration near the Russian border
Researchers in Kuhmo, close to the Russian border, are meanwhile examining what happens to restored peatlands over much longer periods.
At the Elimyssalo Nature Reserve, around 75 hectares of mires were restored about twenty years ago after having previously been drained for forestry. The area later became part of Natura 2000, the European Union’s network of protected sites.
Anne Tolvanen, Professor of Forest Ecology, began monitoring the restoration two decades ago. Researchers are now returning to the same measurement sites to assess changes in vegetation, tree growth and groundwater levels.
According to Yle’s report from Elimyssalo, the water level rose after drainage ditches were blocked and peatland vegetation began to return. But ecological recovery remains incomplete after twenty years.
The process is not linear. Young trees can grow again on restored peatlands, drawing water from the soil and slowing the return of wetter conditions. Tolvanen said similar growth has also appeared on some natural mires, possibly because of rising average temperatures and increasing dryness.
Restored mires can remain difficult to cross for decades
Elimyssalo was not restored for military purposes, and the government study examined defence benefits on mires wetter than those monitored there. Its twenty-year record nevertheless shows how restoration can change the accessibility of terrain.
Tolvanen told Yle that movement was particularly difficult immediately after restoration. A former drainage ditch about one metre wide could become a five- or six-metre-wide waterlogged area after being blocked.
Some of these features become less visible over time. But the wettest restored areas at Elimyssalo remain difficult to cross even two decades later.
This is precisely the type of physical effect that has attracted the attention of defence planners. The ministerial working group says restored peatlands can create natural barriers while also contributing to the recovery of damaged ecosystems.
Environmental restoration with an additional security role
The idea has gained greater strategic significance since Finland joined NATO in April 2023 and its eastern border became part of the Alliance’s frontier with Russia.
The Finnish government is not proposing a continuous belt of restored wetlands along the border. Instead, the June assessment identifies places where environmental restoration and territorial defence can pursue compatible objectives.
The experience at Elimyssalo also shows the limits of treating restoration as a simple engineering measure. Water can return relatively quickly, while ecosystems may need decades to recover and may continue changing as the climate becomes warmer and drier.
For Finland, the next question will therefore be which peatlands are most suitable for restoration and where the environmental benefits can genuinely be combined with the additional objective identified by the Ministry of the Environment and the Ministry of Defence.
