Delineating river network quinary catchments for South Africa and allocating associated daily hydrological information

Nested hierarchical catchments are employed in a wide range of applications (e.g. water resource management, conservation planning, environmental impact or flow assessments, climate change or hydrological modelling, etc.). However, quaternary catchments are fairly large topographical units within which the physiography is highly heterogeneous. This makes quaternary catchment interpolation to finer resolutions incorrect. Presently, there are efforts for sub-delineation of catchments both locally and internationally but these efforts are piecemeal. Thus the consistent and standardized methods and protocols for sub-delineation are lacking, and conflicting boundary extractions hinder data sharing and comparison of assessment and monitoring information. Therefore, this project was initiated to produce a fifth level quinary catchment GIS layer with linked hydrology for which the pre-cursors were altitudinal and river network quinary catchments.