Visbeekvallei (BE)
LOCATION + COORDINATES
Berzegem, Lille (B)
Wet grassland restoration & heathland restoration at 51.276194, 4.807639 decimal coordinates
Wet grassland restoration at 51.240611, 4.789639 decimal coordinates
Swamp forest (Alder carr) restoration at 51.23875, 4.79100 decimal coordinates
Swamp forest (Alder carr) restoration at 51.237361, 4.793111 decimal coordinates
Wet grassland restoration at 51.243833, 4.799361 decimal coordinates
CATEGORY
Demonstration sites for temporary natural water retention
DESCRIPTION SITE
The Visbeekvallei, a reserve of 180 ha, is part of the European Natura 2000 network of protected areas. The Alder carrs (wet Alder forest), wet grasslands, moorland pools, heathland (including old relicts) and pine plantations included, lie within catchment of the river Nete. Surrounding intensively drained farmlands, pine plantations and urban areas limit the capacity for water retention and infiltration. To maximise the water retention and infiltration capacity of the Visbeekvallei, Natuurpunt restored natural depressions of previously drained farmland to temporal wetlands (including species rich wet grasslands and naturally developing wet Alder forest).
In the temporal wet areas with delayed infiltration, historical depressions were restored by removing the nutrient-rich topsoil. At one location the Scottish pines on an adjacent inland dune were cut to increase the infiltration capacity to the restored depressions. In the depression species-rich grasslands orchids will develop whilst the dunes will be covered by heath after 5 years. On three other locations in the south, dykes cut the contact between recreational ponds and the surroundings. To restore the contact and decrease the drainage effect on the groundwater, the dykes were removed and the soil was used to shallow the ponds. On two of the three locations the vegetation can now spontaneously develop to Alder carrs. The third location will be mowed yearly and develop to species-rich grassland.
This will help counter both droughts and floods in the area. The restored temporal wetlands will store more water and allow slow release of the water to the underground throughout the year. Moreover, the measure will increase the self-purification capacity and store carbon in the soil. Similar conversions in the Visbeekvallei have already proven successful, resulting in increased infiltration upstream.
MEASURES
Restoration of natural depressions in the landscape to mesotrophic species rich wet grassland and swamp forest
TIMING
2019 - 2022
BUDGET
€ 609 676 in TOTAL for Heiberg, Visbeek, Den Rooy and Griesbroek investment sites
PARTNERS
Natuurpunt
CONTACT
Pictures by:
Katherine Vande Velde (banner of Visbeek valley fen)
Werner Van Hove (picture of Visbeek valley fen)