A facelift for the pond at Boneffe

10th of November 2017

A large-scale drainage operation is underway for the pond at Boneffe. It will enable this nature site, of great biological interest and listed as one of the Natura 2000 sites, to recover its former appearance and fish population.

The pond of Boneffe, in Eghezée, is a nature site of great biological interest that has been listed as a Natura 2000 site. Together with the wooded terrain at its side, the site covers 13 hectares and is a haven for biodiversity, including amphibians, reptiles, typical flora, insects and birds. The reed bed at Boneffe is of special value. Reed beds are precious natural environments that host threatened species such as the marsh harrier and rare passerines.

A generous donor, wishing to preserving biodiversity in Hesbaye, has bequeathed a sum of money to the King Baudouin Foundation with which to purchase this site and ensure its proper ecological management for future generations.
An initial analysis and report prepared by the Scientific and Technical Committee, which brings together experts from the public and private sector, has highlighted considerable silting up of the pond at Boneffe. This necessitates large-scale drainage.

In practice, the water level has to be lowered. As the pond is emptied, the silt comes into contact with the air, bacteria develop and mineralise the silt and most of it runs off with the water. The remaining silt has to be removed mechanically.
The fish in the pond will be collected as the water level recedes and they will be stocked in water tanks whilst the pond is dried. Following the drainage, an evaluation will be made about the number of carp in the pond since they have a tendency to churn up the mud and make the water murky, which accentuates degradation of the environment. Efforts will also be made to fight the proliferation of the stone moroko, a small but highly invasive and predatory fish of Asian origin.
Renovating the pond will also be good for the reed bed since reeds benefit from an occasional dry period which energises their growth.

In a few months’ time, after its facelift, the pond at Boneffe will have recovered its usual appearance and its fish population. However, it will also have been returned to conditions that are more favourable to the development of biodiversity.