Locates At The Design Stage Prove Valuable

By Jeff Griffin, Senior Editor | April 2009 Vol. 64 No. 4
Best to locate facilities before reaching this stage

Underground utility construction projects most often are classified as either new construction, usually to extend or upgrade services, or replacement/rehabilitation of old or failing buried infrastructure.

However, many projects are to relocate utilities because of street, highway improvements or other types of general construction that makes it necessary to move buried utilities to a new location. Although planning for such projects begins months – even years – before ground is broken, locations of existing buried utilities may not be identified until shortly before construction is scheduled to begin.

Not knowing where facilities are buried during planning can result in costly delays and safety issues once construction is under way.

Mapping utilities before a project begins is one element in the discipline of subsurface utility engineering (SUE), promoted by the U.S. Department of Transportation Federal Highway Administration and, until recently, used primarily on large highway projects.

SUE is an engineering process that goes far beyond locating and marking buried utilities, and although SUE is being applied to projects other than highway construction, many project owners do not retain SUE specialists. For whatever reasons, many project owners and engineer consultants continue to exclude precise utility location from the planning stage.

Early knowledge beneficial

Brian Dorwart, P.E., P.G., vice president of Haley & Aldrich Inc., is an engineer with experience in planning a wide variety of underground utility projects, and he recognizes the value and importance of confirming locations of buried utilities early in a project's planning.

"Knowing where utilities are allows engineers to take them into account from the outset and manage the risk during construction," Dorwart said. "Encountering buried facilities unexpectedly during drilling or excavation can create safety hazards and cost money to pay contractors to stand by while planning adjustments are made. All this results in scheduling delays that are significantly higher than the cost of reliable locating early in the design phase.

"I prefer," Dorwart continued, "to make locates during the permitting phase and while working on the base plan. We do our research, do vacuum excavation verification of utility locations and plan with realistic data.”

Dorwart said that he wants to know the locations of utilities within 25 to 50 feet of the projected bore or excavation path.