Wednesday, November 30, 2016

Subdistrict boundary definition in Nakhon Phanom

Yesterday, the Royal Gazette carried the first announcement related to the administrative subdivision for quite same time - the re-definition of the boundaries of Na Ngua subdistrict in Ban Phaeng, Nakhon Phanom (Gazette). This announcement modifies or clarifies the boundaries defined in 1997, when the boundaries for all subdistricts in Ban Phaeng were defined (Gazette).

One thing which makes the two boundary definitions more difficult to compare is the fact that the coordinates in the MGRS notation are not in the same geographical datum - while the 1997 announcement used the Indian 1975 datum, the new announcement uses the now most common WGS84 datum. In the map below I added all the boundary points defined in the two announcements, but skipped to try to read and interpret the full boundary description to draw the boundary line itself. Apart from two additional points in the southern boundary to Phon Thong, the main difference is the boundary in the north with Phai Lom subdistrict. Interestingly, the new announcement does not redefine the boundary of that subdistrict, either because it is self-evident that the change affects both, or a second redefinition is still pending its publication.