(Editor’s Note: This is the sixth in a series of articles addressing misperceptions that exist about Subsurface Utility Engineering.)
Things were a lot different in 168 when I began working for the Federal Highway Administration. Lots of interstate highway work was underway and many good decisions were being made. Even so, some mistakes were also being made. For example, many decision-makers opted to ignore roadside safety because they thought the new wide highways were sufficiently designed to keep speeding motorists from running off the road.
The same lack of foresight was also true in the 1990’s for Subsurface Utility Engineering (SUE). It seemed so simple then – designating, locating, and data management. How could anyone mess that up? It didn’t take long, though, for opportunists to begin approaching state and local transportation departments and telling them they could eliminate a few aspects of SUE and give them a much better price. The results were so catastrophic that SUE was almost destroyed before it ever got started.
Fortunately for SUE, Jim Anspach and a few other visionaries recognized that a “rule book” was needed to standardize how engineers and owners played the game. Hence, in 2003, the American Society of Civil Engineers published CI/ASCE 38-02, Standard Guideline for the Collection and Depiction of Existing Subsurface Utility Data. A major new aspect of this document was the inclusion of utility quality levels. There were four of them and they provided the following information about utilities shown on roadway plans:
• Quality Level D (QLD) – information about subsurface utilities obtained from existing utility records, verbal accounts, and/or One Call markings
• Quality Level C (QLC) – information obtained from a field review of surface-visible utility appurtenances, including, but not limited to, fire hydrants, junction boxes, valves, risers, and manholes
• Quality Level B (QLB) – information obtained through the application of appropriate surface geophysical methods, surveying, depicting, and professional judgment to determine the existence and approximate horizontal location of subsurface utilities (a utility’s “designation”)
• Quality Level A (QLA) – information obtained by the actual exposure (or verification of previously exposed and surveyed utilities) and subsequent measurement of subsurface utilities, usually at a specific point (sometimes referred to as “locating”)
Utility quality levels are routinely used today on highway plans and are readily accepted as valid by highway contractors, who have in turn been able to reduce contingency amounts in their bids for unexpected encounters with subsurface utilities.
ASCE 38-02 describes the tasks necessary to achieve each utility quality level and how utility
location data and its corresponding utility quality levels can be depicted on design plans. It requires that in order for utility data to be designated on project plans as one of the quality
levels, the data must meet the requirements set forth in the standard, and must be signed and sealed by a licensed, certified, or registered professional engineer, surveyor, or geologist.
ASCE 38-02 and its utility quality levels have been widely accepted in the United States. Both
have been models for standards in other English-speaking countries. ASCE 38-02 is presently being updated to incorporate new and evolving concepts and equipment. We will take a look at some of this in the next issue of Damage Prevention Professional.
C. Paul Scott is Cardno’s National Utilities Liaison. He is retired from the Federal Highway Administration and now promotes Cardno’s utility coordination and subsurface utility engineering activities with state DOTs and other public and private clients.