Research has been carried out to fill knowledge gaps for the transboundary diagnostic analysis (TDA) and to determine the environmental flow requirements of the Fish and lower Orange rivers and estuary.
A number of knowledge gaps were identified in the preliminary TDA and efforts have been made to fill some of these in. In particular:
- the levels of POPs, PAHs and heavy metals in sediments, fish and the eggs of water birds were surveyed throughout the basin, providing a first approximation for many of these chemicals and health risk assessment (see Technical Report 21);
- the hydrology of the basin was further analysed and recommendations were made for improved understanding of the basin’s water balance;
- through cooperation with the Benguela Current Commission and their UNDP–GEF-funded strategic action programme, impacts of the Orange-Senqu River system on the marine and coastal environment were assessed (see Technical Report 1);
- determination of the environmental flow requirements of the Fish and lower Orange rivers and estuary is currently being carried out to provide guidance to the basin states on strategies regarding the release of water from dams (a Study Website has for Environmental Flow Requirements of the Fish River and the Orange-Senqu River Mouth has been established for this initiative).