HISTORY OF SUBSURFACE UTILITY ENGINEERING

Post-82 – University Value Studies

By the end of the 20^th Century there were LOTS of case studies showing the value of Subsurface Utility Engineering (SUE) on individual highway projects around the country. So, it was nice early in the 2000s to get three large-scale studies by civil engineering departments at major universities that looked at a variety of factors where the proper use of SUE played a role in cost and time savings.

Purdue University

In a 2000 study, researchers from the Purdue University Department of Building Construction Management evaluated the quantifiable cost savings of SUE on 71 highway projects in three states and came up with a total savings of $4.62 for every $1.00 spent on SUE. The major savings came primarily from the elimination of unnecessary utility relocations and secondarily from a reduction in delay claims.

University of Toronto

In a 2005 study, researchers at the University of Toronto conducted a study commissioned by the Ontario Sewer & Watermain Contractors Association and investigated the mapping of SUE on nine large infrastructure piping projects in urban areas of Ontario. These projects generally had values greater than $500,000 each, were located in urban areas, and had a large number of buried utilities. The average return-on-investment for SUE, for these particular projects, was approximately $3.41 for each $1 spent. The greatest savings came primarily from reduced delay claims and secondarily from the avoidance of utility relocations.

Pennsylvania State University

In a 2007 study, the Pennsylvania Transportation Institute of the Pennsylvania State University (PSU) conducted an in-depth benefit-cost analysis of 10 SUE projects located in Penn DOT Districts. The study calculated that an average of $22.21 was saved for every $1.00 spent on SUE. When the overall costs of the projects were taken into consideration, the money spent on SUE was minor when compared to the cost savings of avoiding unexpected utility conflicts and unnecessary utility relocations. The Penn State research projected that, in comparison with projects not utilizing SUE, the total cost savings of SUE projects might range from 10% to 15% on a typical project, and that ASCE-38 quality levels A and B should be used on projects based upon the complexity of the buried utilities at the construction site to minimize risks and obtain maximum benefits.

Conclusions

In the 1990s it was hard for me to understand why highway designers would choose to design a project and excavators would choose to dig without knowing in advance what utilities or other objects might be lurking under the ground. It is even harder to understand today with so much more known about the value of SUE than there was then. Even so, many apparently still prefer to save a few dollars and hope they don’t hit anything and have to pay a lot more later.