Background Reedbeds are widely threatened in northwestern Europe by the intensification of farming, natural succession, river management policies and rural drainage. This is the case with the vast marshland areas of the Haine basin, encompassing the marshes of Harchies-Hensies-Pommeroeul, the meadows of Grand Rieu and the Marionville-Douvrain marshes (totalling 6, 500 ha), between Mons and the French border. These areas have long sheltered wetlands of great ornithological interest with large populations of bittern (Botaurus stellaris), little bittern (Ixobrychus minutus) and marsh harrier (Circus aeruginosus). The Haine river basin is right in the centre of the Borinage coalfield, where underground mining has caused major land subsidence. The sinkholes quickly filled up with water, which contributed to the enlargement of the swampland between 1925 and 1950. Since then, however, some areas were drained and filled and the sites of biological interest became fragmented. In addition, a technical problem with pumping in the 1970s had a negative impact by drowning some of the reedbeds. Objectives Facing a complex hydrological situation, the beneficiary, in partnership with the regional authorities, started the project with a detailed study of the hydrological problems of the area, in order to update the plans for the future management and monitoring of key species. To tackle the problem of habitat fragmentation, 60 ha of private land were to be purchased and used, in combination with land swaps, to form new protected zones. Creating coherent blocks of land in this way would make it possible to better manage the reedbeds. Where the reedbeds had been damaged or encroached upon by natural succession or by poplar plantation, mattocking or tree-felling would be applied to help bog vegetation and key bird species to re-establish themselves.