POT HOLING is hydro excavating to locate known subsurface utilities. It is similar to line locating with the exception that this approach is used when the exact position of the utility is known. Potholing is most often used when a contractor needs to verify the depth, size or type of underground utility. Potholing is also utilized for cathodic protection procedures or to safely excavate holes for pole hole installations.
Like most all hydro excavation methods, the process starts with a simple pot hole (8″ to 12″ in diameter). With the mechanical or manual vacuum system hovering the designated surface area, the operator excavates straight down into the ground until the marked, known utility is located.
If the utility is not present, As-Builts are usually consulted for accuracy. Historically, however, As-Builts are not always reliable. In some instances, in fact, they prove to be useless. In this situation, the pot holing procedure gives way to line locating, one of the most efficient hydro excavation methods of locating subsurface utilities.
Applications: subsurface utility engineering