Thurgau restores drained wetlands to combat drought
Sunday 16th August 2026 on 09:30 in
Switzerland
Thurgau is restoring water to former wetlands to bring back lost habitats and make the landscape more resilient during dry periods, SRF reports. The canton says wetlands act as natural water reservoirs and can also reduce the risk of flooding.
The Gampen area in the municipality of Berg, in the canton of Thurgau, shows how land use has changed. Frogs and rare dragonflies now live there, but the land was once used for timber production. At the end of the 19th century, it was considered too wet for forestry, so it was drained and planted with trees. Only a small wetland remained, and it regularly dried out.
In 2022, the canton began restoring the wetland by using sluice gates to retain water. During dry summers, the ground in Gampen remains moist while trees in many other places suffer from water shortages, said Matthias Künzler, head of nature and landscape at the Thurgau Office for Spatial Development.
Wetlands absorb water after heavy rainfall and release it gradually into the surrounding area. This benefits plants and animals and can also lower the risk of flooding, Künzler said.
A beaver later provided unexpected assistance. The animal settled in Gampen and raised the water level by about 30 centimetres with its dams. As a result, the wetland expanded from 3.6 to 8.4 hectares.
The restoration has also benefited wildlife. The rare European tree frog has returned, while the scarce large white-faced darter and small white-faced darter dragonflies have been recorded in the area. Before this, they had only been observed occasionally in Thurgau.
The canton plans to restore or rewet 15 to 20 former fens and wet forests by 2028. The first phase of its biodiversity strategy is now halfway complete, with 37 per cent of the planned measures implemented. The canton has spent 13.1 million francs so far, more than 40 per cent of it provided by the federal government.
Beavers are known for building dams and lodges from branches, twigs and mud. Their structures create ponds, wetlands and new habitats for amphibians, dragonflies, birds and other species. In Switzerland, beavers were eradicated in the 19th century and reintroduced from the 1950s onwards.