By Missy Schrott | mschrott@alextimes.com

Regular visitors to Old Town have likely noticed that something is missing along the waterfront.

Last month, Robinson Terminal North, a massive waterfront warehouse located at 501 N. Union St., was demolished. The demolition was part of RiverRenew, a half-billion-dollar project that involves building a tunnel system under the city to prevent combined sewage from overflowing into the Potomac River.

The combined sewer system in Alexandria has been a problem for years. On a typical day, the system carries combined sewage and rainwater to AlexRenew, the city’s wastewater treatment facility located at 1800 Limerick St. On rainy days, however, the pipes don’t have the capacity to transport the quantity of combined sewage entering the system. As a result, combined sewage overflows into the city’s waterways at four outfalls about 70 times per year, according to AlexRenew.

In 2017, the state legislature passed a law requiring the city to remediate its four outfalls by July 1, 2025. Thus, RiverRenew, a project led by AlexRenew in partnership with the city, was created.

The project involves drilling a two-mile long, 12-foot wide, 100-foot deep tunnel system that will begin at the AlexRenew water treatment facility and end at Outfall 001, which is adjacent to Oronoco Bay Park and just north of Robinson Terminal North. 

Once complete, the tunnel will intercept combined sewage that is headed for the Potomac River and redirect it to AlexRenew, where it can be treated.

The portion of Robinson Terminal North located on the east side of Union Street was demolished to make way for the project. When construction commences, AlexRenew will build an outfall diversion facility underground at the site. The portion of the Robinson Terminal North warehouse on the west side of Union Street will remain untouched by the project.

The warehouse served as a shipping hub for the Washington Post for more than 70 years, according to the site’s current owner, Rooney Properties. The Post decommissioned and sold the warehouse in 2013.

Since then, the warehouse has sat vacant on the waterfront. In October 2015, Rooney Properties submitted plans to the city to redevelop the site and build a 132-room hotel, a 66-unit residential complex and four restaurants. The developers announced in 2016 that they were putting the plans on hold because of unfavorable market response to the proposal.

Rooney Properties has not announced plans for future redevelopment. Greg Hoffman, vice president of Rooney Properties, said the developer does not plan to start any projects until RiverRenew is completed in 2025. He declined to say whether redevelopment would be residential or commercial.

Some residents and organizations, especially the city’s Ad Hoc Monitoring Group on Waterfront Construction, have raised concerns over the years about pollutants at the Robinson Terminal North site. Past industrial activities and the storage of chemicals and petroleum at the site have impacted the soil and groundwater underlying the property, according to a 2015 study.

The Virginia Department of Environmental Quality is also involved in evaluating the site. As a result, future developers may be required to follow certain regulations during construction, such as specially handling soil generated during excavation or implementing groundwater management.

The demolition of Robinson Terminal North began in early November. Once the construction crew from ACECO, the contractor hired to do the project, was set up, the demolition itself took a little more than a week, concluding just before Thanksgiving, according to Kevin Pilong, construction manager for RiverRenew.

Dick Chait, a retired Alexandria resident who lives near Union Street, took an interest in the demolition and spent time watching and chatting with the construction crew.

Chait said he learned that the warehouse was composed of three sections that were torn down one by one. He likened the excavator cutting through metal to “cutting a loaf of bread.”

“It reminded me of a dinosaur going through,” Chait said. “It was this excavator with this long boom and then at the end of it was this shearing scissors that just went in there and chopped away. It had the shape of a large dinosaur going in there and just eating away at it.”

Chait said one of the most powerful moments of the demolition was watching the piece of metal marked with “Robinson Terminal” fall.

“When that came down, that was … historic in a sense that it meant the end of the Robinson Terminal,” Chait said.

Now that the warehouse has been demolished and the scraps hauled away, AlexRenew is poised to begin the RiverRenew tunnel project.

On Dec. 1, AlexRenew awarded the contract to design and construct the system to Traylor-Shea, a company that has completed more than 15 major tunnel projects across the country. Construction on the tunnel is slated to being in Spring 2021.

While the tunnel will stretch two miles and run through Old Town, the average resident likely won’t notice construction unless they’re looking for it at AlexRenew or Outfall 001.

To start, the builder will dig a mining shaft within the AlexRenew footprint, where a tunnel boring machine can go underground, according to Pilong. The boring machine will travel east along 495, then north up the Potomac River until it reaches the Robinson Terminal North site.

“We’re not digging up roadways 100 feet deep or anything like that across Alexandria,” Pilong said. “It’s starting with a deep shaft at AlexRenew’s treatment plant, then we’ll use this tunnel boring machine to mine. Basically, it’s kind of like an inchworm chewing up the ground, and as it chews up the ground, it installs concrete segments in its place.”

In addition to the tunnel, the RiverRenew project involves building underground diversion facilities at Outfall 001 and Outfall 002, which is located near Jones Point Park and Woodrow Wilson Bridge. Builders will also construct a Hooffs Run interceptor to direct combined sewage that would usually discharge from Outfall 003 and Outfall 004, both of which are located along Duke Street, back to AlexRenew.

Overall, the project is estimated to cost between $465 million and $596 million, according to the RiverRenew website. It will be funded primarily through sewer rate increases, as well as state and federal funding.

For more information about the project, go to www.riverrenew.com.

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