In Brazil the cost of collecting hydrological data is very high because drainage basins are large, access is poorly developed and the terrain often difficult. Both inland areas and the more developed coastal regions require knowledge of water resources in terms of basin yield and flood discharges. This paper describes procedures established for the regionalization of flood peaks, mean flows and low flows, based upon existing literature and the kind of hydrological data available in Brazil. The procedures were prepared for use to be used in the Pantanal, a large swamp area in the basin of the Paraguay River (360 000 km2).