The question is could you identify any usable DNA from this waste? And I would expect the answer to be no looking at the bottles. It's a slurry mix of everyone's waste (human or otherwise, lots of stuff gets washed down the drain), so tracing a positive hit on drugs back to the house or person it came from seems like it would be exceedingly difficult to do.

The best you could do is narrow it down to any homes upstream of sample collection, which could be a single neighborhood or an entire city. Or it could be a drifter peeing straight into the sewer grate who doesn't even live in the city.