We have a manhole outside our house and it was inspected like this. I work with GIS for electric and gas companies. I used to keep small ear protectors in the Burley so me and the kids could go up and ask "diggermen" about holes in the road.

Xcel used directional drilling for a plastic gas main down our street and then did sewer intrusion inspections after. A neighbor had their sewer line pierced. It's a hazard because it isn't detectible until the sewer line blocks and then the blade thingy the plumber uses can sever the plastic gas service lateral in the sewer line.

There is a gas overflow valve (like a ball bearing that too much flow can push in to block the pipe) back at the service tee fitting on the main. If that doesn't work then you could have a gas explosion in the sewer or house. It happens and it is bad. Clients give presentations on these projects at conferences (e.g. use GIS to combine the sewer and gas topology to identify where the crossings are.)

That truck isn't for inspecting your sewer, it's for inspecting every junction on that sewer line, 8 hours per day, every day. They will have a map and linear reference showing where every other underground utility (fiber/gas/electricity) intersects it and be recording and cross referencing it in case it needs to be produced in court at a later date.

People are conflating do-you-need-a-$30k-sewer-line "plumber inspection" with this service. This kind of inspection is more like the "assuming tort liability" role that the companies like sitewise serve. Even with the robot done and packed, the operator in the truck was working for a bit, making copies of the videos and tagging them and stuff. If your gas main piercing a sewer causes explosions the settlements can be in the tens of millions.

BigUtility uses trenchless directional drilling to poke a drill horizontally down the street and then laterally to each house saving millions of dollars in open trench costs. The gotcha is that they can't see where they are digging and thus can burn, electrocute, explode or kill taxpayers. The inspections help with sewer maintenance / cleaning but the big money/concern is on the liability for cross bored gas lines.

The robot (the one I saw outside my house) was over $10k and kitting out the whole truck with a crane and the monitors and reels was $90k. They hosed the robot down completely with high pressure water from the truck once it came back out and checked it over for damage. That and the fact that the van guys typically don't go in the sewer is why the van is clean. It's an "expensive equipment" van, not a plumbers van. For comparison the fiber optic inspection a plumber might use is more like $2k and you can rent them.

Depending on the job they can inflate a balloon at the next manhole upstream or even pump/route the sewer through a temp pipe on the street surface (looks like a big fire hose) from the previous manhole to the one after where the van is. That needs 3 crews plus flaggers for traffic. They use a radio to coordinate with the other crews.

With the line blocked for inspection the robot typically just has a film of that nasty sewer grease on it.

They told me the door stays open even in winter because the crane operator / tether wrangler guy is right by an open sewer which is a fall and methane hazard.

The job isn't quick - there might be 300 feet / 100m of line to the robot near the next manhole. Unless they were just looking at one service main, if they were able to leave they must have been winding up already.

The more important question is: is there a sewer manhole where they parked?

If we can surveil people with drones from miles away, what technology are the FBI using that requires guys physically in a van outside a house? If you were going to park outside, why would you use a method that usually blocks the street?

I dug up a pic. If you look carefully you can see two tethers, one for the 4 wheel metal sled that moves it and a thicker one for the camera and lights on the "head" part. The crew used the controls to move the head around until it was looking at my kids and they could see themselves on the second screen (one screen faced out the door.) The kids thought it was cool: https://i.imgur.com/2ltz8bj.png

Story about a fatal explosion caused by horizontal directional drilling piercing a gas main:

https://www.cnn.com/2013/03/13/us/missouri-gas-explosion/ind...

I can't find any conference papers but the industry term to google is "crossbore" and this blog post has some pictures of gas service laterals piercing sewers:

https://blog.envirosight.com/sewer-school-preventing-cross-b...

ESRI page on using GIS to identify the potential crossbores and assign them 90 day inspection windows to try to detect it before the sewer backs up:

https://community.esri.com/t5/gas-and-pipeline-blog/arcgis-f...