Have you ever smelled a sewer?

My sense of smell is really non existent. Unless it it right under my nose. Otherwise I can't smell anything at all.

I've never been on the east coast, much less Washington DC! I can look at the cherry blossoms in National Geographic and not have to put up with the smell.

Ive been to San Francisco, does that count?

Why is this in "Travel"?

I have, yes, when it overflowed into the small yard at the back of my then-home. Had to buy a set of drain-rods, strong rubber gloves and a 5-litre can of Jeyes Fluid (a powerful phenolic disinfectant) to clear the obstruction and clean the yard's concrete surface.

And do my best to avoid wretching or even vomiting while clearing the mess, made more difficult by having to avoid washing it away down a slight slope past the neighbour's back door.

I expect the problem was caused by some idiot flushing something like a used nappy, bundle of paper towels or sanitary-towel down the lavatory.

I smelled a poop factory somewhere in PA when I was little and threw up all over the car :(

Yes. They sometimes overflow around here during floods.

Yes, I have been to Liverpool.