Beyond the Meter by Glenn Fox
Private utility locators, very often Subsurface Utility Engineering (SUE) technicians, supplement the One Call system for excavation and design purposes in these congested underground environments, as well as provide survey grade utility mapping for the project owner. A typical private utility designating or mapping project does include some combination of public and private utilities. Obtaining records from the public utility owners as well as the private property owner (if record drawings exist) is the first step in the process and aids in determining the transition point from public to private ownership. This point is frequently not well defined and left to interpretation by those tasked to mark the facilities, which could potentially leave a gap in the designation of the utility. That point may be a fence line in some cases and a property line in others. I have experienced sites where neither the utility owner nor the property owner was sure of the transition point. A gap in the marking or mapping of a line can lead to the misinterpretation of the path and continuity of a pipe or cable by excavators and engineers, resulting in damage or project delays. Often, the available records are Geographic Information Systems (GIS) maps, which have been compiled from a variety of sources, including outdated paper maps, old site plans and historical knowledge. Most GIS grade maps should be used as a guide only, and are not acceptable for excavation or design. An example of this is illustrated in a sample of a GIS grade map above. On this particular project, utility lines are shown to end in space (see purple arrows with circles depicting a line just stopping), when in reality the line continues in all of these locations.
The congestion of utilities and time needed to investigate all structures combined with fewer connection points than on the public side, require a more methodical and extensive
investigation. This includes inspecting all manholes as they regularly have no identification or have a lid that is mis-labeled. While a contractor may only require that a 25-foot wide corridor be designated (in advance of construction), all the structures near the project limits need to be investigated. The path of those facilities need to be investigatedand confirmed to determine if they are in conflict or not.
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