I’ve got a question for any damage prevention professionals out there that could offer some insight.
Within the last year, I had trouble with a contractor who refused to spot our high profile water facilities along several major roadways (all were between 8″ and 24″). The boring contractor installing conduit for traffic signals, refused to pothole any facilities, claiming they used GPR to verify depths. My problem, was the accuracy of the equimpment and personnel using the GPR was in question. As one example, in less than a 20′ area, they scanned the GPR in 3 spots (photo attached). In which the depths were noted at 3’4″, 4′, and back to 3’5″. This utility was an eight inch cast iron pipe that comes in lengths of 20′ each and there are no elevation changes, so it is impossible for the line to fluctuate eight inches. The contractor wanted to give us three inches of clearance.
When I tried to stop the contractor from crossing us without potholing, they refused and I went to higher local authorities, but the local authorities governing the project allowed them to continue without potholing, stating that the GPR readings would be adequate. In this process, I found that there isn’t much enforcement of the laws regarding excavation procedures until the utility is actually damaged, where in this case, I guess the negligence of standard procedures would have been more obvious. And as a note, our utility did not get damaged, but we do not know how close they came to us when crossing our water main. Anyone dealt with a similar situation? If so, how’d you handle it?
Thank you,
Joseph Martin



