Terra Discovery

Subsurface Utility Locates & Investigations

The term SUE is often misunderstood and properly refers to a branch of civil engineering that deals with the design of underground utilities by assigning “quality levels” to existing records and as-built drawings. 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 in order to present a unified approach to classifying the quality of data associated with underground utility mapping. Since that time many people have come to think of SUE as the process of collecting the data rather than the quality level assessment that follows.

Terra Discovery is positioned to assist owners and professional engineers complete their project SUE requirements by providing:

  1. Records Search. Existing records, e.g. plans, as-built drawings and utility company mapping can be collected and the information from these consolidated onto base drawings. Drawings can be converted to CAD and geo-referenced if required. (CI/ASCE 38-02 – Level D)
  2. Field Review. Visible surface features associated with utilities can be field assessed and their positions referenced to property lines and other surface features to confirm and/or update the base drawings. Items confirmed can include power poles, transformer pads, manholes, hydrants, telephone pedestals, etc. (CI/ASCE 38-02 – Level C)
  3. Designating. Existing and abandoned utilities can be marked and mapped using EM tracing and ground penetrating radar methods and their positions confirmed and/or updated on the base drawings. (CI/ASCE 38-02 – Level B)
  4. Test Pits. The exact size, horizontal and vertical position of a utility can be verified at specific locations by test pits. This typically involves excavation by hydrovac method, measurement by surveyor or using survey equipment, and backfill and reinstatement of original surface. (CI/ASCE 38-02 – Level A)