Habitat Restoration

The Dokka Delta Wetland Centre has a lot of experience with mire restoration and surveying to find potential mires for restoration. We also have a lot of expertise concerning the restoration of semi-natural meadows and mires, and our current work includes looking at the potential to restore meandering river channels in Etnavassdraget and a small lake in Hadeland.

NV performs diverse restoration work on behalf of the official conservation authorities, municipalities and the private sector. The Wetland Centre has the competence and the equipment to carry out every part of a restoration project. We take care of the project planning, surveying, preparation, excavation/contractor work, monitoring and any additional work after the project is complete.

 

Some of our earlier and current projects include:

 

  • The restoration of several drained marshes.
  • The restoration and burning of vegetation to restore habitat for Dracocephalum ruyschiana.
  • The restoration of overgrown meadows.
  • The restoration of previously managed mires.
  • Designing management plans for previously managed meadows and mires.
  • Creating fords in streams and rivers to prevent large forestry machines from damaging freshwater pearl mussels.
  • Restoring habitat for freshwater pearl mussels.
  • Restoring Dracocephalum ruyschiana populations.
  • Investigating the potential of restoring meanders of the River Etna in Etnedal Municipality.
  • Investigating the potential of restoring a small lake (Hovtjern) in Gran Municipality.
  • A team to perform the maintenance and restoration of previously managed meadows and mires in partnership with the County Governor for Oppland.

 

Flood preventative effect of mire restoration.

The drainage of mires in forest areas in Eastern Norway took place across large areas of land during the 1950s and 1960s. This has affected the landscape's ability to act like a sponge and store water that falls as precipitation. It has also reduced the biological diversity that existed in our mires. The loss of mires has also affected the ability of forest areas to store CO2.

 

The Wetland Centre, together with several other interest groups, has discovered the need to document the flood preventative effects that we benefit from when we restore mire areas, and in 2016 started a feasibility study. The partners in this study are DNV, NINA, NIBIO, Vassdragsforbundet for Mjøsa, Randsfjorden vannområde, and the County Governor for Oppland. These partners have received grants awarded to projects that aim to protect water environments from the Norwegian Environment Agency. We wish to use the project to develop up to date methods of locating drained mire areas, plan hydrological mire investigations of selected test areas, restore selected areas and measure the effect of the restoration measures. The Wetland Centre utilises LIDAR data and topographic maps to survey for potential areas of restoration. We have visited 62 of the 296 drained marshes that were identified as potential areas for restoration in Nordre and Søndre Land. Of these 62 we identified seven mires that we consider most reasonable to restore when we consider cost effectiveness and benefits that can be achieved through reduced runoff.

The result of the work in autumn 2016 was a change to the hydrological characteristics of an area of land around 1km2, with over 650 m2 of formerly drained mire restored. The Wetland Centre is now looking to continue this work and plans to undertake hydrological investigations and ecological monitoring of several mires in Veståsen. These will be conducted before and after restoration to document the flood preventative effect of mire restoration.

The effect of mire restoration as a flood prevention measure has so far been poorly investigated. It is therefore of great interest to investigate this effect in areas where there has been comprehensive historic drainage and where the flood risk is increasing, such as hillsides along Randsfjord.