Drinking the Potomac: Loudoun Water Prepares for the Future

The Loudoun Soil and Water Conservation District recently criticized Loudoun Water for allowing the water to stop flowing over the dam on Goose Creek.

The Virginia Department of Environmental Quality and the Virginia Department of Conservation and Recreation found no legal grounds for the LSWCD’s complaint, but the brief spat between the conservation district and Loudoun Water highlighted the big question for the utility: With 65,000 homes and businesses relying on the authority for water and more connecting every day, how will it keep up with the demand?

Loudoun Water estimates it uses 25 to 30 million gallons of water on an average day. Right now, that is a mix of water drawn from Goose Creek and purchased at cost from Fairfax Water.

“We make those decisions day-to-day on the basis of what produces the best drinking water in our system for the public overall,” said Loudoun Water Deputy General Manager Tom Frederick. “That’s looking at monitoring chlorine levels and other parameters that are very important, from our standpoint, on a daily basis.”

Although Loudoun Water has the ability to draw up to 50 million gallons a day from Fairfax Water and an additional 18 million gallons a day from Goose Creek, for a total of 68 million gallons of water a day, the utility knows that won’t be enough to keep up with the county’s growth in the future. It estimates by 2040 its customers may need 90 million gallons of drinkable water a day.

So Loudoun will start drinking directly from the Potomac.

The construction site at Loudoun Water's new Potomac River intake.
The construction site at Loudoun Water’s new Potomac River intake.

Loudoun Water’s Potomac Water Supply Program will pump water from the Potomac River near the Leesburg Water Treatment Plant, into new storage at a current Luck Stone quarry in Leesburg, and into the new Trap Rock water treatment facility under construction near the Dulles Greenway.

“When we open the Trap Rock facility and the new assets are built and ready to go, that has an initial production capacity of 20 million gallons per day, and that basically at this point will replace the Goose Creek system,” said Loudoun Water Executive Director of Stakeholder Relations Mark Peterson. “Now, exactly what we’re going to do with those assets is still to be determined. We still do plan to use the Beaverdam Reservoir.” Eventually, according to a Loudoun Water report in May, the Potomac Water Supply Program will be able to produce 40 million gallons per day.

That same report to the Loudoun Water board of directors shows the project overall still within its $214.9 million total budget, but construction of the $145 million Trap Rock water treatment facility and finished water transmission line is running six months behind schedule, and the $33 million Potomac pumping station eight months behind. Currently, work is expected to wrap up in June 2017.

Loudoun Water has also contracted with Luck Stone to store up to one billion gallons in one of its Leesburg quarries, which will soon be retired. The water utility could potentially have access to that quarry as soon as 2020.

The view from the bottom of the vast concrete shaft by the banks of the Potomac River at the site of the future pumping station. [Loudoun Water]
The view from the bottom of the vast concrete shaft by the banks of the Potomac River at the site of the future pumping station.
[Loudoun Water]
            “The arrangement we have with them in a Memorandum of Understanding is, as they retire future quarries, we have the first right of access to those quarries, so it’s not interfering with their production,” Frederick said. “What we’ve looked at in our studies at this point is, Quarry A (the first quarry Loudoun Water will take over) can satisfy our needs well into the future.”

Quarry A will give Loudoun Water one billion gallons of storage capacity. As Luck Stone finishes mining other quarries in the area, those quarries could give Loudoun Water up to 8 billion gallons of storage capacity, allowing the utility to bank water for droughts and as a precaution against pollution in the Potomac.

“The water is good quality, and it’s acceptable to meet public health standards all the time,” Frederick said, “but we’re looking for the best water quality.”

rgreene@loudounnow.com
@RenssGreene

A view from inside the underground tunnel at the future pumping station on the Potomac River. The utility expects to be able to pump 40 million gallons of water per day through these pipes to its water treatment and quarry storage facilities. [Loudoun Water]
A view from inside the underground tunnel at the future pumping station on the Potomac River. The utility expects to be able to pump 40 million gallons of water per day through these pipes to its water treatment and quarry storage facilities.
[Loudoun Water]