Shantipriya,
You did not mention the name of that Tamang basti, I would be interested to overlay a 6-miles radii circle centering Ason/Indrachowk and see if indeed there is an outlier. About thimi bhaktapur, where do they shit early morning in the core-area? Can you write me the name of the tole, nearby monument or any such identifiable location where you see those early morning activities? I will verify with the ground truth information. I am not talking about newly developed region where the sewage infrastructure are not done yet.