DRAINAGE REGION HIERARCHY

Drainage regions of South Africa (experimental)

Map of South Africa's primary and secondary drainage regions using the USGS GTOPO30 data set.


Please note that these are fairly spartan pages, so you will need to use the "Back" key a lot.
While java-based mini-GIS systems for the Internet are becoming common, you may still need a simpler method for displaying geographic data using a ready-made hierarchy of maps at different resolutions.

This is an example using the Department of Water and Sanitation drainage classification system to zoom into an area of interest. Arc/Info AMLs adapted from one by Ian Thomas formerly of USGS Patuxent generated the maps. You are welcome to use these pages for any application of your own, but you will quickly see that keeping all possible maps of several layers of a hierarchy takes up a lot of space!


Please contact Michael Silberbauer at the Institute for Water Quality Studies if you have any queries.
Obsolete page, created 2001-08-22.

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