By Brian Trompeter
The proposed Tysons West Wastewater Pump Station, which would provide 25 times more capacity than the existing facility, substantially accords with Fairfax County’s comprehensive plan, members of the county’s Planning Commission unanimously agreed Oct. 25.
The Building Design and Construction Division of the Department of Public Works and Environmental Services (DPWES) submitted proposed plans for the pumping station, which would be situated on 3.03 acres of county-owned land at 8608 Leesburg Pike, just south of the Dulles Toll Road.
That property, which is accessible from Industrial Way, most recently was used by the now-demolished Tysons Self Storage facility.
The county’s existing Tysons Dodge Wastewater Pump Station has been located in the site’s northeast corner since 1969 and handles up to 1 million gallons of wastewater per day. The county would continue to use that pumping station until the new one was built and operational.
The new pumping station would be part of the $110 million Tysons Wastewater Conveyance Systems Modifications Project, which also would include a force main and about 2 miles of gravity-sewer pipe. Officials expect design work to continue through summer 2025 and for construction to be finished in summer 2028. The project would be funded by sewer-service and -availability charges.
The proposed pumping-station location would reduce potential issues with utilities, infrastructure and construction impacts at another site, county planning staff said.
The proposed new facility would be able to pump up to 25 million gallons of wastewater per day – enough to fill almost 38 average-sized Olympic swimming pools – to the Noman Cole Jr. Pollution Control Plant in Lorton and would lessen the risk of wastewater overflows and backups, county officials said. The pumping station, which would use a 36-inch-diameter force main, is intended to accommodate massive expected growth in Tysons and provide reliable long-term service, they said.
The new 11,200-square-foot pumping facility would have screen, pump, electrical, odor-control and supervisory-control-and-data-acquisition rooms, plus wet and dry wells.
It also would have a 2,500-square-foot building with a new standby-power diesel generator and adjacent, above-ground fuel-storage tank capable of storing about 12,000 gallons of Grade No. 2 diesel fuel. The generator building would comply with the National Fire Protection Association’s containment provisions and have leak-detection and monitoring systems.
Those two buildings would be located on 1.5 acres of the site; the property’s remaining half would accommodate a future yet-to-be-identified public use.
The station would be unmanned and function around the clock, but undergo daily inspections and routine maintenance. County officials expect the facility would generate only one vehicle trip per day for such work.
The facility’s three one-story buildings would have a “contemporary aesthetic” featuring concrete and metal panels on its exterior. The county would construct the building’s envelope using pre-cast concrete panels, ribbed form liners, sandblasting and color admixture. Multi-colored, perforated metal panels would conceal the front mechanical equipment while permitting optimal air flow.
A decorative metal fence would surround the buildings and provide security and screening. Evergreen trees would screen the northern portion of the site from public view and “amenity panels” would perform the same function to the south.
“I really appreciate the attention to the aesthetics of this facility,” said Planning Commission Chairman Phillip Niedzielski-Eichner (Providence District). “To me, it comes across, at least in the portrayal that we’ve seen, as high-quality and sensitive to the fact that Tysons is this evolving urban center and this pump station will be visible from some portions.”
The proposed pumping station is “probably our highest-priority project right now” because of projected capacity needs in Tysons, said Thomas Grala, a Fairfax County engineer.
The facility would be “very industrialized” and have four 470-horsepower pumps capable of moving wastewater over a 250-foot-tall hill, which would require a considerable amount of power, he said.
The county would take steps to minimize odors from the facility, which would be located near other Tysons developments, Grala said.
To try and meet a goal of retaining the first inch of stormwater on site, county officials plan to install an underground basin and use permeable pavement, officials said.
“Unfortunately, we have a very high groundwater table on this site,” Grala said. “It’s about 3 feet below grade, so that’s limiting our ability somewhat to deal with this 1-inch containment on site and possibly infiltrating that into the ground. But we are trying to fine-tune our design and to maximize our potential to reach that goal.”
Planning Commission member Mary Cortina (Braddock District) said the facility’s location was appropriate, but she hoped the county could meet that stormwater-containment objective.
“If DPWES can’t reach the standard in Tysons, it’s a cringe, you know, if we’re asking everybody else to do it,” she said. “To the extent that you can do that, I think it’s important to do that, because it’s in our comprehensive plan that the public facilities have to do it, too.”
Controlling emissions and noise from the site’s generator will be important, said Planning Commission member John Ulfelder (Dranesville).
“I think the last thing that the county needs is people to come in and complain about what [the county has] installed and what it’s doing to their quality of life,” he said.
