Namibian Map Systems

Datum Conversion

Datum transformation parameters from Schwarzeck to WGS84 datum are only accurate to 30m countrywide.
Generally used parameters consist of only a translation/shift and no rotation and no scale factor.
Parameters are available from:

• DMA (US Defense Mapping Agency) - EPSG 1226

  From Schwarzeck to WGS84: DX: 616 DY: 97 DZ: -251
  From WGS84 to Schwarzeck: DX: -616 DY: -97 DZ: 251

• Chief Directorate Surveys and Land Information; Mowbray; South Africa - EPSG1271

  From Schwarzeck to WGS84: DX: 615.64 DY: 102.08 DZ -255.81
  From WGS84 to Schwarzeck: DX: -615.64 DY -102.08 DZ 255.81

• Dr Charles Merry (UCT - University of Cape Town)

  From Schwarzeck to WGS84: DX: 616.8 DY: 103.3 DZ: -256.9
  From WGS84 to Schwarzeck: DX: -616.8 DY: -103.3 DZ: 256.9

A free app to transform between different coordinate system in the WGS84 and the Schwarzeck datum is available here:

Local transformation parameters vary according to the region with a RMS of about 1.5m for example the north-eastern region (see Projects - Transformation Parameters) and a RMS of about 0.3m in the central area.

Namibian Cadastral Survey Datum

The Namibian Cadastral Survey Datum is the same as the older map system and is generally known as the Schwarzeck datum. It is based on the Bessel 1841 spheroid and uses the German Legal meter instead of the International meter (1 GLm = 1.0000135965 Im).
The projection is a south-orientated Transverse Mercator projection with two-degree panels as listed in the table above.
The effect of the GLM is very small for local areas (14mm over 1000m) and is usually taken into account by surveyors by including it into a scale factor. The effect is the largest for projected coordinates with large distances from the latitude of origin (22 S), with an effect of up to 7.5m in the north and 10m in the south of Namibia.

Prior to the official introduction of the above projection in the 1950's and 1960's, the longitude of origin was either 15 or 18 E. On most cadatral documents these are general referred to as preliminary system and are annotated as Lo.22/15 Prelim or Lo.22/18 Prelim. There are however numerous other cadastral survey system present in Namibia. These systems can typically be seen on some of the older cadastral farm diagrams, but also on some of the older general plans. Most of these are local systems that were established before the official Schwarzeck system covered the whole country. Some of these systems are the 'Base North (V) System' in northern Namibia, the 'Schwarzrand System' in South-western Namibia, the 'Kaiser-Wilhelm-Berg System' around Windhoek, as well as the 'Uitdraai System' east of Otjimbingwe.