SUE - Subsurface Utility Engineering

About SUE

In 2003, ASCE defined SUE as an engineering practice in CI/ASCE 38-02, Standard Guideline for the Collection and Depiction of Existing Subsurface Utility Data. The importance of this standard is that it indicated that, in addition to FHWA, a prominent national engineering organization defined SUE as an acceptable engineering practice and provided guidance for applying it on projects.

Benefits of SUE

SUE benefits both project owners and utility companies in the following ways:

  • Makes for safer projects
  • Exposes potentially hazardous utilities
  • Reduces utility-related delays
  • Prevents unnecessary utility relocations
  • Helps eliminate utility outages / service interruptions
  • Reduces costly schedule delays / shut downs
  • Avoids negative media exposure associated with damaged utilities

The Four Quality Levels of SUE

QL "D" is the most basic level of information for utility locations. It comes solely from existing utility records or verbal recollections. QL "D" provides an overall “feel” for the congestion of utilities and is useful primarily for project planning and route selection activities.
QL "C" involves surveying visible utility facilities (e.g., manholes, valve boxes, etc.) and correlating this information with existing utility records (QL "D" information). Its usefulness, therefore, is primarily on projects where utilities are not prevalent, or are not too expensive to repair or relocate.
QL "B" involves the determinations of the existence and horizontal position of virtually all utilities within the project limits. This activity is called “designating”. Information provided by QL "B" can enable the accomplishment of preliminary engineering goals. Slight adjustments in design can produce substantial cost savings by eliminating utility relocations.
QL "A" also known as “locating”, is the highest level of accuracy presently available and involves the full use of the subsurface utility engineering services. It provides information for the precise plan and profile mapping of underground utilities through the nondestructive exposure of underground utilities, and also provides the type, size, condition, material and other characteristics of underground features.