GPRS Scans Concrete for Light Installation on Hoan Bridge

GPRS Scans Concrete for Light Installation on Hoan Bridge

Daniel W. Hoan Memorial Bridge illuminated with red, white and blue lights.
Since October 22, 2020, the Daniel W. Hoan Memorial Bridge has illuminated the night sky with its multicolor light show. GPRS is proud to have provided precision concrete scanning services to ensure that the intricate lighting system could be safely installed.

When the sun goes down along the Milwaukee River, the lights along the west side of the Daniel W. Hoan Memorial Bridge burst into life.

Since October 22, 2020, the Wisconsin landmark has illuminated the night sky with its multicolor light show. The colors and patterns of the lights are never the same from one evening to another, as everything from sports teams to nonprofit organizations are celebrated.

GPRS is proud to have helped breathe new life into this Milwaukee landmark, providing precision concrete scanning services to ensure that the intricate lighting system could be safely installed along the 47-year-old bridge.

“It was a very cool thing to be a part of,” said GPRS Project Manager Chase Loppnow. “Whenever you’re driving downtown, and you see the bridge lit up in different colors for something to do with the city… It was something very cool to be a part of.”

Loppnow was part of a GPRS team that also included Project Manager Alex Kleinschmidt and Area Manager Paul Mandella, who spent roughly two weeks conducting ground penetrating radar (GPR) scans along the 607-foot, tied-arch bridge to ensure that the lights could be installed safely and without causing structural damage to the bridge.

A worker scans the side of a bridge with ground penetrating radar.
GPRS conducted ground penetrating radar scans every 18 inches along the side of the Daniel W. Hoan Memorial Bridge in preparation for the installation of a lighting system.

Strapped into safety harnesses, the team conducted scans every 18 inches along the side of the bridge where the lights were to be installed to ensure the new infrastructure would not clash with existing electrical conduit running through the structure.

Protecting the existing conduit was vital, as a utility strike during installation of the lights could have shut down the bridge for an extended time. And nobody wants to be responsible for closing a bridge that carries tens of thousands of cars a day into a major city.

“There was already electrical conduit running through the bridge, and they had to install anchors for the lights,” Loppnow said. “So, when they were drilling, they didn’t want to hit those systems.”

Originally known as the Harbor Bridge, the Daniel W. Hoan Memorial Bridge connects Interstate 794 in downtown Milwaukee to the Lake Freeway across the Milwaukee River inlet. It’s named for Daniel Webster Hoan, who served as mayor of Milwaukee from 1916 to 1940.

The bridge itself underwent a complete structural overhaul that was completed in late 2016. Then, in May 2018, a private, non-profit campaign dubbed “Light the Hoan Bridge” sought to install a lighting system along the bridge with the goal of offering “a platform for building awareness and improving community pride.”

The project was completed, and the bridge officially lit for the first time on October 22, 2020. A fundraising initiative is currently underway to illuminate the east side of the bridge.

A worker scans the side of the Daniel W. Hoan Memorial Bridge with ground penetrating radar.
GPRS Concrete Scanning Services ensure your project can stay on schedule, your budget remains intact, and your people remain safe.

GPRS has since returned to the Hoan Bridge to conduct further concrete scans as ongoing maintenance and upkeep has occurred on the nearly 50-year-old structure. Mandella says that his time working on the bridge to help install the lights was “a unique project that will be on the top of the list for a long time.”

“When driving past at night, seeing the lights, it’s cool to think I was a part of it,” Mandella said.

How GPRS Scans Concrete

GPRS Project Managers use ground penetrating radar (GPR) scanners and electromagnetic (EM) locators to locate utilities, post-tension cable, rebar, and other infrastructure within concrete slabs.

GPR is a non-destructive detection and imaging method which uses radio waves to “see” underground or within a concrete slab. The waves react with anything they encounter – both metallic and non-metallic objects – to create a series of hyperbolas on the GPR’s display or a wirelessly connected tablet. GPRS Project Managers undergo industry-leading training and certification to be able to interpret those readings to tell you what was found and precisely where those objects are located.

EM locators work in concert with GPR to detect electromagnetic signals running through underground utilities. They can also emit their own signal through a known line to determine the direction it runs through your jobsite.

By using GPR and EM locating technology together, GPRS Project Managers can fully visualize your project area. We have achieved and maintain a 99.8% accuracy rating on the over 500,000 utility locating and concrete scanning jobs we’ve completed in our 23-year history.

To support our confidence in our Project Managers, we introduced the Green Box Guarantee. When we place a Green Box within a concrete layout prior to you cutting or coring that slab, we guarantee that area will be free of subsurface obstructions.

If we’re wrong, we agree to pay the material cost of any damage.

Keep Your Workers Safe

At GPRS, your company’s safety is our primary focus.

We know risk mitigation is one of your top priorities, which is why, since 2018, we’ve sponsored Concrete Sawing & Drilling Safety Week.

From January 29-February 2, 2024, our safety experts will travel the country visiting jobsites to offer complimentary presentations about the top risks to your workers and the ways these risks can be mitigated.

We’ll discuss the dangers of silica exposure, the hazards to avoid when sawing, cutting, or drilling concrete, and the importance of having a personal safety plan.

To date, we’ve educated over 20,000 construction professionals through CSDSW. In 2023 alone, over 150 companies proved their dedication to the safety of their workers by hosting CSDSW talks at their offices or jobsites.

There’s still time to sign your team up for their free CSDSW presentation. Click the link below to schedule your presentation today!

Frequently Asked Questions

How does concrete scanning work?

Concrete scanning involves using a non-destructive imaging technology like ground penetrating radar to visualize the subsurface infrastructure inside a concrete slab, including conduit, post-tension cable, and rebar. GPR scanners emit radio waves into the concrete, and those waves interact with anything they encounter. Those interactions are displayed as hyperbolas on a GPR reading, and a qualified technician can interpret that reading to tell you what was found and exactly where it is located.

Can GPR find voids in concrete?

GPR equipment can identify areas where voids could possibly be occurring, and the boundaries of that potential void. It cannot measure the void’s depth.

Why scan concrete before cutting or coring?

Because severing structural components such as post-tension cable or rebar or slicing through electrical conduit or other utilities can have costly and potentially dangerous repercussions.