Ezemvelo KwaZulu-Natal Wildlife, with whom we’ve been discussing the new map series since 2019, can’t meet on making inputs into the drafts of the first two maps until near the end of April. The delay is unfortunate but I have put a lot of thought into how we can move this process along as speedily as practicable, bearing in mind the extreme need for revised maps. With this in mind I have prepared two special maps for their meeting, which anyone interested may access and comment on at the link below.
I have taken the existing EKZNW maps and first aligned them accurately upon the official 1:50 000 topo maps [SG or Surveyor General maps]. In this regard they match with some precision, regarding contours, rivers, etc but not paths or roads. Apparently the topographic info on these is based on the same projection as the SG maps but the paths etc are not, being based on the Cape Datum instead. This curious mixture of two systems is unprecedented and has led to many problems, not least of which is that many paths appear in effect about 150 metres+ east and south of where they actually are, without any reference to the hills, cliffs, gullies and river beds around them. As you know there are no long/lat coordinates given for features on these maps and because of the above it would be impossible to provide them.
To illustrate this I have overlayed in purple the path and roads system as it appears on the drafts of the new maps. This ‘purple’ layer has been geo-referenced and is 100% based on actual gps readings in the field and/or interpolated with information from the SG maps, Google Earth and other photo sources, and inasmuch as it is subject to the same errors as any human-generated information I am satisfied that it is 99.5% as accurate as I can make it given the limitations of scale.
I have then added question marks where problems arise. Red question marks refer to paths and roads shown on the EKZNW maps that cannot be found and are not explained by the datum shift outlined above. Orange question marks refer to paths shown by EKZNW as ‘Minor Paths’ but which have been recently reported only as ‘ways to go’ – nor can any trace of them be found on photos. A few purple question marks refer to paths found in the Cathedral Peak research area which do not appear on the EKZNW maps and where I don’t know if they are included in the public MTB system, or should be excluded.
Your comments on any of this would be welcome, the DropBox link is at https://www.dropbox.com/s/ujnj2fmpx22n25d/Compare%20Paths%20Maps%201and%202.zip?dl=0
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