They must mean Southwest Detroit, I don't know your city limits except the bridge to Windsor, Ontario, Canada and the noise that's driving some people crazy in some neighborhood of Windsor coming from the US side of the river, on that ugly testament to man's destruction of it's real homeland, Earth, on Zug Island, research by Canadian scientists says it comes from that hyper industrialized area and island where the air is so bad people vomit from breathing it if not used to it. Anyway, Zug Island has this US Steele factory on it, it closed for 2 years and was reopened in 2010 and that's when the Windsor Hum started. And the place looks creepy as hell, DHS is protecting it (why, it's a foundry), agents all over the island, only ways into it are 2 bridges, one train bridge and one road for employees where they can't enter without a swipe card + PIN.
What I don't understand is that the people on the other side in Detroit, well River Rouge technically, do not seem to hear it. So I say there was something built underground the foundry while it was closed and they're testing non-lethal weapons on poor Windsorians who don't deserve it, the shit they used in Iraq, at much less insane levels. But still, if I had to live in Windsor, I would try to leave as east inside the town as possible. Ask canadians in the Canadian Opioid Thread, because H in Canada is almost only in the southern Ontario peninsula that goes down to Detroit, Vancouver. Calgary, Ottawa and Montreal have small scenes but that's it. This is just what i can tell from what I read over here and elsewhere. The H comes from the US, so the people there get Detroit Heroin if it's really Heroin and not Heroin+fent or a fent derivative.
As for why Philly isn't as scary as Detroit...if Detroit's Midtown area didn't exist, which is the only safe place in the city where anybody can walk around without trouble, Philly has nowhere the economic difficulties and outright meltdown that industrial cities in Michigan are experiencing,I can't believe the Worker's State is ruled by Republicans and illegal things like an Emergency Manager. That governor Snyder needs to be arrested for his many crimes. If you heard of what they're doing to Rev. Pinkney in Flint over the toxic water thing....that's why Michigan is scarier.I visited Philly, I didn't go to west philly, I was going to my Habs game in Conference Finals against the Flyers in 2010. And I had veritable philly cheesesteak sandwich, not with cheez whiz, with real damn melting tasty slightly spicy cheddar. Now I make myself some home. Sorry I can't be of more help, even if I was living in Detroit, not sure I could help ya (rules over here).
But yeah, what's in southern ontario is probably the same H as in Detroit, so maybe look that up.