As an aside: I think a lot of people here would be surprised at the amount of technology (and surveillance) that goes into setting speed limits and placing stop signs in residential areas.
I make sure to come to a complete fucking stop at every one of those signs. Partially because I hate the feeling of rolling through stop signs, but partially out of spite lol.
my lines are 4" PVC, if we somehow clog those, someone call me an ambulance.
TBH sewer main inspections should be required any time someone wants to rent a house out.
I had a company(wrongly) tell me I needed a new septic tank and drainfield installed, and quoted me out at 7800.
Which is way, way more work and parts than a sewer line.
It took just a couple minutes (less than 5) to go look this up and find the video, for what it's worth.
Maybe it's an NSA wet team! Wet, because they do sewer inspection work. :)
I agree though that it seems more plausible to just be a real sewer van.
I just went to Google maps to the address written on the van's passenger door and lo and behold, Google did drive down the alley behind and while this is a larger vehicle and not just a van, that's their look (they also have black versions if you look around): https://www.google.com/maps/@33.7851188,-118.211276,3a,67.3y...