A multi-year renovation project is about to begin at Arlington’s Water Pollution Control Plant.
The $32.2 million first phase will be part of an almost $200 million undertaking “to make the facility cleaner, greener and ready for the future,” county officials said in announcing the upcoming start of the initiative.
The plan — dubbed Arlington Re-Gen — implements the recommendations of the 2018 Solids Master Plan, which identified options for modernizing facilities. Upgrades to the plant’s liquid-treatment facilities and equipment were completed in 2011.
The upcoming Arlington project, funded through user fees, has been in the works for several years, and is unrelated to the recent DC Water sewage spill in the Potomac River, county officials said.
Activities in the “Early Work Package” will focus on grading, building demolitions, relocation of utilities and foundation work for future treatment systems, county officials said. Work will take place entirely within the plant’s fenced boundaries on S. Glebe Road.
Wastewater treatment operations will continue without interruption during the work.
Later this year, the five-year “Main Work Package” is expected to begin.
“Crews will build the new solids-handling facilities that form the core of the Re-Gen program, including thermal hydrolysis and anaerobic digestion systems to produce renewable resources using modern dewatering and screening equipment, improved truck loading and advanced odor control,” county officials said.
According to public-works officials, the process of cleaning wastewater from every Arlington toilet flush generates biosolids, nutrient-rich materials that can also be treated and reused.
When completed, Re-Gen will enable the county to transform this material into Class A biosolids and renewable natural gas, reducing the plant’s overall carbon footprint, officials said.
Commissioning and phased startup of the new facilities is expected to occur in 2031.
The Water Pollution Control Plant treated an average of 21 million gallons of wastewater each day from homes and businesses in the 2025 fiscal year. Nearly 20% of the plant’s flow comes from the neighboring localities of Alexandria, Fairfax County and Falls Church, which contract with Arlington to provide services.
Clean water is returned into the environment at Four Mile Run, then the Potomac River, before finally reaching the Chesapeake Bay.
Currently, county residents with a median water usage of 48,000 gallons annually pay $835 in water and sewer charges. County Manager Mark Schwartz’s proposed fiscal 2027 budget would increase rates on residential customers approximately 1.6% to $848.
The rate increase is expected to yield an additional $2.4 million for the Utilities Fund, which is separate from the county’s General Fund and pays operating and maintenance costs, debt services and reserve funding for water and sewage-treatment operations.
The county also pays a designated share of improvement costs at the Washington Aqueduct, which supplies wholesale water to the county system.
For those interested in getting a close-up look at the Water Pollution Control Plant, tours for groups of between 5 and 12 people are offered weekdays from March through June and again from September to December.
The tour is two hours long, with the first hour in the classroom followed by an hour-long guided walk.
