Subsurface Utility Engineering

Keep your projects on track and on schedule

Subsurface Utility Engineering is the practice of identifying underground utilities and structures on engineered construction drawings for design purposes. The data that is recorded on the drawings can have 1 of 4 different quality levels, which describes how accurate or reliable the information is.

Subsurface Utility Engineering is more than just locating underground utilities for construction activities. Subsurface Utility Engineering (SUE) is typically performed during the design phase of a construction project, and it is proven to solve conflicts with underground utilities before the construction phase even begins.

CI/ASCE 38-02 QUALITY LEVELS

Quality Level D

Quality Level D data is the least accurate and reliable data. This data is typically derived only from existing records or oral recollections. There is often no field investigating or evidence to support the data.

Quality Level C

Quality Level C data is slightly more accurate than QL-D data because it involves surveying and plotting visible utility surface features, such as manholes, fire hydrants, transformers, etc. and correlating this data with information obtained from Quality Level D sources like utility records.

Quality Level B

Quality Level B data is much more accurate and reliable utility data than Quality Level C because it involves the use of surface geophysical equipment to detect and designate the location of underground utilities. The location of the underground utilities and structures are then surveyed and plotted.

Quality Level A

Quality Level A data is the most accurate and reliable information because the data is derived from physically exposing and measuring the underground utility. The data collected from exposing, or “day lighting” a utility can include the utilities exact depth from grade, elevation, size, heading / orientation, material composition, and general condition.

SUBSURFACE UTILITY ENGINEERING WHERE YOU NEED IT

You’ve got questions, we’ve got answers

What is Subsurface Utility Engineering?

What quality level of SUE should I use for my project?

The Quality Level of data you may need for your project can certainly vary depending on the type of project and what the information is needed for. Engineering of a new building or addition, or installation of gravity piping will likely require a minimum of Quality Level B data, with a few areas of Quality Level A data at key locations. If you are interested in creating a map of your existing conditions, Quality Level C data may be more cost effective, but less accurate.

If you are not sure what quality level is best for your engineering project, call us at (888) 232-5959 and we’d be happy to answer any questions you have.

Why would I use SUE on my project?

The use of SUE on construction and engineering projects has proven to reduce costs associated with unexpected utility conflicts discovered in the construction phase of a project. In addition to the cost savings, understanding the utility conflicts in advance will help keep your projects on schedule and within the planned budget.

How much could budget could we save using SUE?

In 1996, Purdue University performed a study on behalf of the Federal Highway Administration (FHWA) to quantify the cost savings potential of employing Subsurface Utility Engineering on various highway projects. Although this study is in need of updating, Purdue University concluded that utilizing SUE could produce a cost savings of $4.62 for every $1.00 spent on Subsurface Utility Engineering. Qualitative savings were non-measurable, but it is clear that those savings are also significant and may be many times more valuable than the quantifiable savings.

How is utility data collected and reported?

Typically, utility data will be designated in the field using various surface geophysical pieces of equipment such as electromagnetics and ground penetrating radar. Once the utilities have been designated, they will be surveyed using established project survey control and added to project drawings in the format of your request. Utilities can be merged with existing files, or provided as a stand alone file that may be referenced in.

Can you work with the existing project surveyors?

Yes! If your project already has an established survey crew, Utility Locator® can work alongside to provide the accurate utility data they need to depict existing utilities on your drawings.