The compiled data is surely ...

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The compiled data is surely available.  But, you need to browse through the net in case you need for a particular country.  More importantly, you need to ascertain whether they would meet your requirement. You may please check for these links if you wish help from India:

https://www.niir.org/directory/directory/water-amp-waste-water-treatment-plants/z,,c8,64,32/index.html

https://in.kompass.com/a/waste-water-consultants/7275002/