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Drinking WaterArchitecture

Markets

Local Government

A state-of-the-art treatment facility and transmission system 

The 20 mgd plant will support Loudoun County alongside a new raw water intake on the Potomac River, raw water transmission mains, off-line raw water storage using a series of abandoned quarries, and finished water transmission. Our experts designed a total of 5,000 linear feet of water transmission and powered the system with 40kwh of renewable energy. Taken as a whole, the county’s Potomac Water Supply Program will provide a reliable and solid foundation for future growth. 

A best-in-class drinking water plant 

Starting with bench- and full-scale testing, we designed a facility with multiple layers of treatment and sophisticated transmission systems. 

Architectural excellence that matches engineering brilliance 

Our architects married aesthetics and functionality, paired with imaginative touches, like a sloping roof that allowed for water flow without rain leaders. 

An 800 square foot laboratory space  

The functional and appealing lab space gives Loudoun Water a facility that’s the envy of its peers. 

Sustainability from the ground up 

Trap Rock boasts solar power, water- and energy-efficient design, preservation of natural surroundings, and the capacity to expand in the future.  

“The Potomac River has supported Loudoun County’s growth for decades, but the river requires the additional off-line quarry storage to sustain population growth while maintaining minimum flows in the river,” says CDM Smith discipline leader for water treatment Bill Dowbiggin. "This project will establish safe, sustainable water supplies for the future."

“The program that’s in place right now is set to evolve over the next 50 years. It’s been great to work with a utility that is so forward-thinking; it’s allowed us to implement innovative strategies during every step of the project and find the best solutions for Loudoun County residents.” 

An industry‑leading drinking water plant

Curious to learn more?

Connect with an expert to find out how we delivered this project.

Person in a blue plaid shirt against a dark background.

Bill Dowbiggin, PE, PMP, BCEE

Water Treatment Discipline Leader

Bill Dowbiggin has designed more than 60 major WTPs and earned numerous industry awards for his distinguished service to the water supply field.

Practices

Drinking WaterArchitecture

Markets

Local Government

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