The Regional Municipality of Durham, Canada, conducted a Ritson Road reconstruction project, utilizing a $91,000 Subsurface Utility Engineering investigation that revealed discrepancies, including an 8-foot deviation of a gas main, resulting in canceled relocation, corrected inaccuracies, and a 2.1 return on investment according to the University of Toronto's research team.

In Oshawa, ON, Canada, the Regional Municipality of Durham sought to engage in a full-depth reconstruction of the 4-lane Ritson Road due to deteriorating pavement conditions.

The municipality elected to use the opportunity to renew an existing water main and construct a separate storm-water collection system.

Due to previous incidents involving inaccurate information about underground utilities and the age of the area’s infrastructure, which increased a likelihood of inaccurate/incomplete utility records, a comprehensive SUE investigation was conducted. 

QL-B designation was completed along the proposed alignment for designating gas, electrical, and telecommunications utilities. A total of 43 test holes were made to confirm the designation and provide the exact depth of utilities at critical locations.

The information collected by the SUE investigation was compared to the information provided by owners of various utilities.

The most important discrepancy that was identified involved a gas main, which was believed to be in conflict with planned waterline but was found to be 8-ft. away from the location indicated by the utility’s records. 

Consequently, the relocation of the gas main was canceled. In addition, several other inaccuracies in the as-built drawings were detected and corrected, thus eliminating potentials conflicts and subsequent claims.

The cost of the SUE investigation was $91,000, which was approximately 2% of the project’s total cost. The University of Toronto’s research team estimated the return on investment for the investigation to be 2.1.