GPRS Completes Utility Mapping Project for a College in Pennsylvania

College campuses offer a unique perspective on the importance of utility mapping.

These multi-acre properties consist of decades-old structures sitting beside new construction and significant renovation projects. Because of this, the underground infrastructure on these properties is a web of both active and abandoned lines.

That was the case when Brian Gifford, GPRS project manager, mapped the infrastructure of a historic college in Pennsylvania, which had no previous documentation of its buried utilities.

Gifford spent nearly two months conducting utility locating and mapping across the college’s 112-acre campus to create accurate as-built documentation. That information is uploaded to SiteMap, GPRS’ cloud-based infrastructure mapping software solution.

School officials can use this information for future O&M, renovation and repair purposes. The information is secured and accessible 24/7 from a computer, tablet or mobile device.

“At least a couple of the buildings here are over 100 years old,” Gifford said. “They don’t know where their utilities are located… So that’s kind of the purpose, why we’re out here, is to give them [a map] of all their utilities for the entire campus.”

Gifford’s work provided valuable information of all subsurface utilities on campus. This included gas, power, sewer, water, telecommunications, as well as other unknown lines identified during the project’s investigation.

History Behind Utility Mapping for College Campuses

GPRS is familiar with the utility locating and mapping needs of U.S. universities. In fact, it entered a long-term partnership with the University of Toledo (UToledo) to provide the school with scans and maps of their utilities, gas lines, state-of-the-art video pipe inspection (VPI) of water and sewer pipes, and, ultimately, complete 3D scans and maps of their entire campus, above and below ground.

“I found a lot of old lines,” Gifford said. “There were four water lines running down the campus’ main drive, and two of them were abandoned. They’re cut off in certain spots, but they’re still running through the campus.”

Anytime the university needs to dig – either to renovate or repair – and they’re relying on out-of-date or incomplete as-built utility data, they risk severing a utility line. A single utility strike can cost a facility, on average, $56,000 and can take up to eight weeks to repair based off research from Finch Brands. On a college campus, that strike can interrupt classes and extracurriculars, and even endanger the lives of faculty and students.

How GPRS Locates and Maps Utilities

GPRS primarily deploys a combination of ground penetrating radar (GPR) and electromagnetic (EM) locating to locate buried utilities and other underground obstructions.

GPR is a non-destructive detection and imaging technology that uses radio waves to identify subsurface elements either underground or within a surface such as concrete. The GPR scanner emits radio waves into the surface, and then detects the interactions between those waves and buried objects such as electrical conduit, rebar, gas mains, and more.

These interactions – sometimes referred to as “bounces” – appear on a GPR readout as a series of hyperbolas that vary in size and shape depending on the type of material that was located. Professional utility locating specialists like GPRS’ Project Managers (PMs) are specially trained to interpret this data to provide accurate location and depth information that can be used to safely plan excavation projects.

To complement GPR, GPRS PMs also deploy EM locators, which detect the electromagnetic signals radiating from metallic pipes and cables to allow for accurate locating and mapping of those utilities.

These signals can be created by the locator’s transmitter applying current to the pipe, or from current flow in a live electrical cable. They can also result from a conductive pipe acting as an antenna and re-radiating signals from stray electrical fields (detected by the EM locator functioning in Power Mode) and communications transmissions (Radio Mode).

Using the Best Technology

GPRS project managers are trained to utilize the best technology for the job at hand, considering a variety of factors including soil conditions and visible surface features as they plan the best method for providing accurate utility locating services.

This training is underpinned by Subsurface Investigation Methodology (SIM), the training program GPRS Project Managers adhere to for utility locating, concrete scanning, and video pipe inspection.

SIM teaches that the use of multiple locating technologies – including GPR and EM locating – is the best way to ensure a redundant confirmation of investigation results. It also provides PMs with a step-by-step approach to collecting subsurface data, so their results are repeatable and accurate.

It’s because of this training regimen that Gifford shares he can tackle a job as big as mapping an entire college campus’ underground infrastructure.

“Generally, we just break the scan area up into sections and take it bit by bit,” he explained. “Move piece by piece… some utilities, I may not be able to find in one location, but then when I move, I can pick it up and trace it back to its source.”

GPRS project managers also use GPS and Real-Time Kinematic (RTK) positioning technology to geo-locate their utility locating results and upload that data into SiteMap. Every GPRS customer receives a PDF and .KMZ file of their utility map. They also receive a complimentary SiteMap Personal subscription so that data is at their fingertips where and when they need it.

Blake Bacho is a content writer at GPRS.