Water Management Areas: Interactive Web Map Application

URL: http://www4.dwa.gov.za/BASE_WMA_multi/

General Description

This Web Mapping Application displays Water Management Area (WMA) and drainage region (basin/catchment) information together with other base data layers. The application is useful for determining in which WMA or drainage region a specific area falls. Users can navigate around the map to an area of interest or use predefined tasks to find / zoom to a specified Quaternary Catchment, WMA or 1: 50 000 Topographical Map Sheet.

What is a Water Management Area?

The National Water Act (Act 36 of 1998) requires that water will be managed at regional or catchment level within defined Water Management Areas (WMAs). A WMA is an area established as a management unit in the National Water Resource Strategy within which a catchment management agency will conduct the protection, use, development, conservation, management and control of the country's water resources. The boundaries of WMAs are broadly based on different levels of drainage region boundaries, but also include some administrative demarcations.

What is a Drainage Region?

A Drainage region, also referred to as catchment or river basin, is defined as the geographical area in which all water runs down to the lowest point following the natural land slope and collects to form a river, a lake or as groundwater before finally reaching the sea. Primary drainage regions may be further sub-divided into secondary, tertiary and quaternary drainage regions.

Data Disclaimer:

This Web Mapping Application was compiled by the Department of Water Affairs. Due to the scale of capture and/or representation, a degree of error is inherent in all maps. The maps are intended for use only at the published scale. Detailed surveys or analyses completed at much larger scales may differ from the maps. Where data was obtained from different sources or captured at varying scales, the combination of data layers may result in the apparent mismatch of certain features.

Note: To facilitate ‘seamless’ viewing, a geographical coordinate System was used. As this lends itself to some horizontal distortion the application is not suitable for conducting accurate measurements.

Although the greatest care has been taken to ensure that data used is up to date and accurate, the department gives no warranty, express or implied, as to the accuracy, reliability, completeness, utility or assumed suitability for a particular purpose or use.

Data Sources and Acknowledgements

Data

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Source

Coastline, International Boundaries, Cities, Towns, Roads, Rivers and Dams.
1: 50 000 Topographical Map Sheets / Chief Directorate: National Geospatial Information,
Department of Rural Development and Land Reform
Provincial Boundaries / Municipal Demarcation Board
SPOT5 Satellite Imagery (Degraded to 10m resolution in terms of copyright agreement) / South African National Space Agency (SANSA)
Government contract with SPOT Image
Water Management Areas, Drainage Regions, Flow Gauging Stations and Settlements / Department of Water Affairs

Comments and other services

Web Map Applications
Author and administrator – comments or suggestions on this service are welcome / Helena Fourie / Tel (012) 336-7811
e-mail
Digital spatial Data
Corporate data exchange and management / Nicolene Fourie / Tel (012) 336-8950
e-mail
Cartographic services
Map production and printing / Dorette Piekaar / Tel (012) 336-8950
e-mail