This report deals with the possibilities to fit the Barbier-brook in the Controlled lnundation Area of Kruibeke, Bazel en Rupelmonde that was planned according the Sigmaplan. The so called CIA-KBR is situated upstream Antwerp. The CIA-KBR will be inundated when a certain flood on the river Schelde overflows the lowered river dike. The result is a decrease of the peak of the flood. A dike at the polder side will fulfill the defensive function during the period of inundation. This dike is called the "ringdike". The Barbier-brook cuts through the CIA-KBR. Within the CIA the Barbier-brook is diked in since the 13th century. Further on in this text these dikes will be called Barbier-brook dikes. Nowadays, the area between these dikes forms the storage for the Barbier-brook.The study participates in the preparations for the CIA-KBR. Co-ordinated by the Institute of Nature Conservation in Brussels some studies for possibilities of nature development within the CIA-KBR are carried out.In this report the technical possibilities to fit the Barbier-brook in the CIA-KBR as weIl as the perspectives for nature developrnent are studied. The perspectives for nature development can be split in:.nature development influenced by the Barbier-brook.nature development influenced by the Barbier-brook and a controlled reduced tide, controlled reduced tide stands for: a tide controlled by culverts for the in- and outlet of water from the river Schelde with a reduced tide amplitude with an average of 0,25 to 0,5 m.This last perspective corresponds most to the historical natural situation of the area, which consists of freshwater marshes and mud plains.To be able to work out these aspects it is necessary to carry out also a study ofthe water quality and quantity of the Barbier-brook.No discharge data from the Barbier-brook are known at all. Based on the discharge data of the Kleine Molenbeek near Liezele, which has a similar catchment area except the size, the discharge frorn the Barbier-brook could be abstracted. To do so, the surface ...