The Northside Project

Finding Flow: Engineer Heather Ullinger on Leading the Northside Interceptor Tunnel

An engineer who talks to humans instead of just blueprints? That’s Heather Ullinger.

As the City of Akron’s Senior Engineer, Heather has played a pivotal role in shaping the Northside Interceptor Tunnel (NSIT) — one of the city’s largest and most transformative infrastructure projects. Featured in the latest episode of Sewers, Streams, and Waterways Renewed, Heather shares how she found her way into engineering and what it’s like to guide complex underground work that will protect Akron’s waterways for generations to come.

In the episode, Heather discusses the collaboration behind NSIT and other major initiatives under the Akron Waterways Renewed! program, including the Aqueduct Street green improvements and the future removal of the Gorge Dam. She also reflects on the human side of engineering: the community partnerships that drive progress and the perseverance it takes to see long-term projects through.

Heather’s perspective offers a rare look inside the dedication and teamwork that make the NSIT project possible, and reminds us that building a cleaner, healthier city starts with people who care deeply about its future.

🎧 Listen to the full episode: Sewers, Streams, and Waterways Renewed – featuring Heather Ullinger

NSIT at the City of Akron Blue Heron Homecoming

On Saturday, October 11th, 2025, some of the Northside Interceptor Tunnel (NSIT) team were proud to participate in the City of Akron’s Blue Heron Homecoming, hosted by Akron Waterways Renewed! The festival celebrated Akron’s progress toward cleaner waterways and provided a hands-on way for the community to learn about local water infrastructure, environmental stewardship, and the projects shaping our city’s future. Learn more about the event here.

This year, NSIT was represented by three interactive booths that brought the underground world of tunneling and stormwater management to life. Granite engaged visitors with a sand table and a set of pipe segments that allowed participants to “build their own tunnel,” illustrating how the NSIT conveys combined sewer and stormwater deep below Akron. Thomarios showcased a working baffle drop shaft model, where attendees could watch water flow through a series of chambers that slow and control the descent—mirroring how real drop shafts dissipate energy to protect the system’s integrity. Meanwhile, Accenture invited families to craft their own rain sticks, offering a fun, creative way to talk about rainfall, runoff, and how stormwater travels through the city’s collection systems.

Also in attendance was our engineering partner, AECOM, who led a hands-on demonstration showing how pipes are engineered to control water flow. Their “ball drop” activity gave visitors a chance to see fluid dynamics in action—illustrating how slope, diameter, and alignment affect the way water moves through a system. It was a simple yet effective way to connect engineering principles to the real-world challenges of designing underground infrastructure like the Northside Interceptor Tunnel.

The Blue Heron Homecoming drew a steady stream of curious visitors—families, students, and residents eager to explore and learn. At our booths, guests had activity offering a hands-on look at how Akron manages water beneath the surface. These interactions transformed complex engineering into tangible experiences, helping people understand how the NSIT project protects the Cuyahoga River and improves local water quality. The event also gave our team the opportunity to connect directly with the community, answer questions, and share in the excitement of Akron’s ongoing environmental progress.

We’re grateful to Akron Waterways Renewed! for hosting such an engaging event and to everyone who stopped by to learn more. The enthusiasm and curiosity we saw throughout the day reaffirmed why projects like NSIT matter—not just for cleaner water, but for a stronger, more informed community.

The Northside Interceptor Tunnel is more than just construction, it’s a commitment to cleaner water and a healthier future. By improving the Cuyahoga River, this project helps restore a natural resource that connects our community.

But the impact doesn’t stop with the environment. Through the All-Akron Student Engineering Program (AASEP), high school students joined the NSIT team as summer interns. They explored careers in engineering and construction, gained hands-on experience, and saw firsthand how a major project like the Northside Interceptor Tunnel comes to life.

What exactly is a Combined Sewer Overflow, or CSO? This video explains CSOs and how the Northside Interceptor Tunnel (NSIT) is part of the City of Akron’s Akron Waterways Renewed! program to nearly eliminate them.

Learn how the tunnel works, why it’s critical for protecting the Cuyahoga River, and how Akron is meeting EPA clean water goals for a healthier community and environment.

On April 23, 2025, tunneling officially began on the Northside Interceptor Tunnel—a major milestone for the project! Extending from the Chuckery Metro Parks area to Front Street, the tunnel will span 6,660 feet beneath North Hill and is expected to reach breakthrough in approximately five months. With round-the-clock coordination and specialized crews in place, progress will continue steadily as the tunnel boring machine, Elaine, advances beneath the city.

On February 12, 2025 crews worked deep inside the Front Street Drop Shaft, executing a critical installation 120 feet below the surface. With precision and coordination, a 54-inch HOBAS pipe was carefully placed into an 84-inch excavated opening at the base of the Rack 35 shaft. Once positioned, the pipe was secured with grout and final shaft concrete, ensuring long-term stability and performance. Watch the video below to see this important construction process in action.

On January 23, 2025, the Northside Interceptor Tunnel team in Akron, Ohio, pulled off a massive feat—rotating Elaine, our 450-ton Tunnel Boring Machine, about 30 degrees to align with the next phase of tunneling. Working 150 feet underground, the crew navigated tight clearances and freezing temperatures to make this move happen. After the turn, Elaine was carefully pushed into the starter tunnel, where final assembly is now underway. Check out this engineering milestone from above!

The NSIT project, spearheaded by the City of Akron, has been featured in the Fall 2024 issue of DDC Journal, a publication renowned for highlighting excellence and innovation in development, design, and construction. The article details the project's groundbreaking approach, environmental benefits, and community impact as a key advancement in Ohio's water infrastructure. The publication recognizes the project's role in transforming regional waterways, showcasing the collaborative efforts and strategic planning that have made it a cornerstone of Akron's environmental future. To learn more, visit DDC Journal's Fall 2024 issue and read the article on page 127.

On January 6th, 2025, City of Akron Mayor Shammas Malik visited the NSIT construction site to highlight the project's progress and its significance for Akron's environmental goals. Elaine Marsh, the environmental advocate for whom the tunnel boring machine "Elaine" is named, was also present to emphasize the importance of this initiative in protecting the Cuyahoga River. Their visit underscored the city’s commitment to improving water quality and addressing sewer overflows through this transformative project.