Not just the UK.
In the US, dowsing for utility locates around construction sites happens quite often. A guy in a hard hat and utility company logo orange safety vest hops out of a truck and starts waving bent welding rods around and spray painting lines on the sidewalk.
I have seen or heard stories of power, water, electric, sewer, gas, communications, even fuel lines in a bulk tank farm dowsed, marked, and signed off.
I have used utility locating services countless times, calling them in for various stages of various construction sites. I have never once witnessed them using dousing rods of any sort. Although they have been wrong on occasion, even with their high tech equipment.
The one dousing incident I did see was rather different.
We were digging a deep (20 ft.) building excavation which required a soil nail wall as a temporary retaining wall. For those unfamiliar with the process, this involves digging down in stages, about six feet deep at a time. At each stage long holes about 3" dia. (ranging from 10 to 25 feet or so) are drilled horizontally into the exposed cut, then a length of heavy rebar is inserted into the hole and grouted into place. Finally a skin of heavy welded wire fabric is placed to cover the face of the cut, which is then sprayed with a layer of concrete several inches thick, and large metal plates are slid onto the rebar and held in place with bolts to secure the wire reinforced concrete skin.
At the start of any such installation it is necessary to ensure that the drilling does not damage any immediately adjacent utilities. On one job we knew that there was a 12" water main somewhere close to the reach of the longest rebar pins scheduled for that section of the SN wall.
The utility contractor we were using on that site had installed that water main a couple of years earlier, so we asked them to have it located for us so that we could be sure to miss it.
The foreman who had installed that pipe told us that would be no problem ... and this is when the welding rods came out.
We confirmed that the marks he had painted were not going to be within reach of any of our soil nails.
We managed to drill four holes. The fifth started gushing water, and shut down the water service to several of the university's adjacent multi-story lab buildings. The pipe in question was, it seems, about 8 ft. closer to the excavation than where he had located it.
Matters degenerated quickly from that point.
The water main in question had been turned over to the county water service well before these events.
They wanted to see the documentation for the locating services who had been notified. Only long years of mutual business contact between the county and our utility contractor avoided significant legal action. The contractor bore all the expenses incurred by the incident, which were considerable, and that is beyond the cost of repairing the water line.
The county also made them hire an independent locating service which provided actual physical location in three dimensions of
all the remaining utilities, including the rest of the water lines (There were others on other sides of the building footprint), gas, electric, sewer, storm, etc., which were shown on the site utility drawings to be within 15 ft. of the longest possible soil nail. This was a non-trivial form of locating which involves using a high pressure air drill that can drill down to the pipe without damaging it. It is very expensive, and
very time consuming ... and was what they had been trying to avoid in the first place.
