A Tunnel Worth Cheering–Alexandria Wins National Award

ALEXANDRIA, VA – The question of the day was thus: Could a two-mile sewage tunnel, 12-feet wide, running 115-160 feet underneath Alexandria, be a thing of, well, beauty? Oh, yes, it can be; just ask Alexandria’s Vice Mayor Sarah Bagley.

“When you think about what it’s going to accomplish, absolutely,” she said proudly, under azure-blue skies on Sunday, as an endless stream of traffic from Reagan National Airport flew overhead.

“It’s going to keep sewage off of our streets, out of people’s homes, and out of the Potomac River.” Among the small but enthusiastic crowd of project supporters at the celebration, which took place at Oronoco Bay Park, one woman sported a “Hazel” T-shirt, in homage to the massive tunnel boring machine that carved out the tunnel.

The tunnel, in turn, is named in honor of Hazel M. Johnston, “a passionate environmental justice advocate from the 1970s until her death in 2011,” according to the Roy + Patricia Disney Family Foundation, which bestows an annual environmental justice award in her name.

Alexandria’s pollution problem

This very project will solve an incredibly, forgive us—but if you know you know—stinky problem, as we have been reporting since its inception in The Zebra.

That’s because Alexandria, at present, is one of more than 800 towns and cities across the United States that have a combined rainwater and sewage system. And when it rains as little as a quarter inch, according to RiverRenew, the torrent of water overwhelms the city’s inadequate waste-water treatment system, causing it to release raw sewage into the river and local waterways, and even sometimes—yes—onto the streets. But that will soon be a thing of the past, as the new infrastructure project is projected to reduce sewer overflows by 98 percent when it comes online next year.

“I just wanted to get some residents together, and we are really excited to talk about just how cool we think this project is, and honestly, just get together and look at the progress on a beautiful day,” Bagley continued.

Little did she know, but Bagley was talking with a sympatico reporter who spent nearly 20 previous years writing about infrastructure, and also about the fact that few Americans truly understand the need or the price tag of infrastructure. Or appreciate the fact that in virtually any town or city in America, you can turn on a water spigot and drinkable water flows out.

Or that you can just as reliably flush a commode, and if you’re not tied into a septic system, you’re probably tied into a rather sophisticated “machine” for treating that dirty water—and such machines don’t come cheap.

So yes, there is plenty to nerd out over when it comes to the RiverRenew Tunnel, which is owned by AlexRenew, the infrastructure authority managing construction of the new system.

For one thing, the tunnel system, when operational, will capture combined sewer overflows from four existing locations, known as outfalls, which were built in the 1860s. It will then direct that flow into the AlexRenew wastewater treatment plant, instead of allowing it to spill into the Potomac River, Hunting Creek, and Hooffs Run, as it currently does.

On average, in fact, Alexandria spews some 140 million gallons of untreated water into these waterways every year, as a result of some 70 combined sewer overflow events, according to AlexRenew. The RiverRenew project, however, is projected to reduce that to less than four combined overflow events each year, with less than 17 million gallons of untreated water entering the Potomac River and local waterways.

Project is best observed from Oronoco Bay Park

The best place to visually capture the massive size of the RiverRenew project is to look southward from Oronoco Bay Park, which affords a look at the massive crane and concrete works seemingly jutting out into the Potomac. On the other hand, however, most people rounding the bend from Pendleton Street in Old Town as it curves onto North Union Street have little idea that the rather generic-looking, fenced-off construction site houses one key component of the largest infrastructure project in Alexandria’s history, with a price tag of $615 million.

Located just south of Oronoco Bay, that component is the enormous, 100-foot-deep shaft (see photo), that will connect the four historic outfalls and collect the combined sewage overflows via the new tunnel.

RiverRenew wins prestigious Tunnel Achievement Award and cover story placement in Tunnel Business Magazine

On August 10, AlexRenew proudly announced that the RiverRenew Tunnel System had been awarded the 2025 Tunnel Achievement Award, which recognizes “projects that demonstrate innovation and teamwork and provide benefits to the community,” according to the magazine.

The coveted national award, granted to one project each year since 2012, comes from Tunnel Business Magazine in partnership with the “Breakthroughs in Tunneling” Short Course at the University of Denver.

In addition, the “RiverRenew Tunnel System” is examined in lengthy detail as the cover story in the August 2025 issue of the magazine. The project was recognized for “the project team’s innovative planning and design, the successful navigation of complex urban and geological challenges, and the far-reaching clean water benefits that will result,” according to the magazine.

“We’re building this system for a brighter future for Alexandria and the region,” AlexRenew CEO Justin Carl said in the Tunnel Business Magazine article. “We’re helping to achieve the vision of a fishable, swimmable Potomac River in the future.”

The Waterfront Tunnel completed its underground journey in March 2024, with the entire project on track for completion by the revised July 2026 deadline. The project also includes the installation of 2,500 feet of new pipeline near Hooffs Run and a pumping station that will keep the tunnel dry.

The $615 million project was mandated by a 2017 Virginia law requiring the remediation of combined sewer outfalls by July 1, 2025—a deadline that was eventually extended by one year. The design/build team of Traylor-Shea was awarded the $454.4 million project five and a half years ago.