Some of you may be aware that the Gazettes are an authoritative source of
open data and maps published by the Government, but they are not usable
when published in the original PDF format.

Example of some of the maps available in the gazettes:
- Notifications of protected area boundaries and eco sensitive zones by
MoEFCC: Link
<https://archive.org/details/in.gazette.central.e.2017-08-10.178009/page/n27/mode/2up>
- Changes to irrigation command areas (Goa): Link
<https://archive.org/details/in.goa.egaz.2526-48.SI/2526-48-SI-OG/page/2440/mode/2up>

The wildlife protected area and ESZ boundaries are especially valuable
since they restrict various commercial and industrial activity in the
vicinity of ecologically sensitive areas. The notified maps however are
usually in low resolution without georeferencing making it close to
impossible to use it to investigate if a map location falls in a protected
area.

*Georeferencing workflow*

To overcome this, have been trying out seamless a workflow to georeference
and digitize the maps on OpenStreetMap that will open up the data for wider
uses. The workflow is described here:
https://github.com/publicmap/amche-atlas/issues/230#issuecomment-4866156628

It makes use of the IIIF manifest.json available on any document on
internet archive to seamlessly load a Gazette map in the AllMaps.org
<https://editor.allmaps.org/> georeferencer using a SOI toposheet as a
basemap. The georeferenced image can then be loaded as a TMS layer in OSM
or QGIS for digitizing. The process involves no download/image
processing/upload steps at all and is completely on the cloud with free
tools.

Following this method, was able to digitize the core and eco sensitive zone
boundaries of Tansa <https://www.openstreetmap.org/relation/3963830> and
Tungareshwar <https://www.openstreetmap.org/relation/21057460> Wildlife
sanctuaries in significant detail in under an hour. Hope it is useful for
those working on environmental/legal matters.

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