CANAPE

CANAPE: Zuidlaardermeer’s reedbeds are growing

15 December 2022 - Published by Harry Mach
On the border of Drenthe and Groningen lies the beautiful lake of Zuidlaardermeer. It is popular for recreation, but also surrounded by wildlife, with bittern, buzzards and the occasional eagle. The management of this lake is important to the surrounding community, not only for recreation, but as part of the wider flood defence that the healthy and restored peatlands that feed the River Hunze provide.

Like many shallow European lakes, it has suffered from Eutrophication, and a subsequent decline in water plants (macrophytes).

CANAPE has supported a substantial programme of work to model and design the next phase of restoration in this lake, drawing on the experience of the partners, and working closely with the community.

Zuidlaardermeer was mapped to consider for reed bank creation, with substantial vegetation surveys carried out through 2020 and 2021. These areas are divided in 7 zones for construction works.

Map of the lake, showing 7 zones labelled around the edgers.

Selected zones: 1. Islands Meerwijck, 2. Rows of piles on the Foreshore (two locations); 3. Wolfsbarge; 4. Broekbos Noordlaren; 5. Reed land; 6. Small lake Oostpolder; 7. Oostpolder (small-scale measures)

Zones 1, 2, and 3 have been selected for phase 1 for the construction works. The other zones are part of the next phase. 

Following the mapping work, Waterschap Hunze en Aa’s is now able to begin the construction phase, seeking to create an additional 20ha of reedbed along its banks. This will involve rewetting currently drained peat, reducing emissions, whilst giving the lake extra filters to help remove the excess nutrients from its waterways.  In particular, this will compensate for the phosphate loading, which is creating poor water quality in the lake.

an excavator loading reeds into a truck

Construction underway at the site

Another key part of establishing the macrophytes is trying to reduce the wind fetch. The wind blowing across a lake creates wave action that can disturb plants, create turbidity, and lead to areas without plants. Inserting still areas behind read beds and creating islands will support the recovery of plant life in the lake.

Work will also be carried out with land owners in the local area and local nature conservation organizations  to develop a "peatland vision" for a longer-term sustainable use of the catchment around Zuidlaardermeer, improving the overall health of the local ecosystems.