Fairfax Water to replace and expand 71-year-old tank in Idylwood

A water tank erected in Idylwood around the time of the Korean War is on its last legs, Fairfax Water says.

The water authority is seeking to replace the 71-year-old Poplar Heights tank with a bigger, elevated tank that will be able to hold approximately 1.25 million gallons of water, according to an application submitted in December to Fairfax County’s planning department.

“The Elevated Tank is required to provide a more consistent level of water service within the existing distribution system and will improve system reliability, water quality and water flow and pressure for many customers in Fairfax County and Falls Church,” Fairfax Water’s statement of justification for the application says.

Fairfax Water took control of the existing 700,000-gallon tank at 7407 Tower Street in 2014 when it acquired Falls Church City’s water system. The facility was built in 1952, predating the creation of the neighborhood’s civic association.

The authority says it “identified multiple system deficiencies” in areas previously served by Falls Church, including in the Poplar Heights Pressure Zone west of the city. The zone extends from Shreve Road to Graham Road Elementary School.

Issues with the Poplar Heights tank included low water service pressures, insufficient storage volume and “water quality concerns associated with the existing standpipe water tank.”

To set the stage for a replacement, Fairfax Water spent five years buying the single-family residential lots around the tank. Two of the four houses will be demolished, along with the existing tank, as part of the project.

According to the application, the new, elevated water tank will be approximately 100 feet tall — roughly the same height as the current tank. The site will have no public access, but Fairfax Water staff will visit weekly to conduct maintenance and repairs between 7 a.m. and 4 p.m. Monday through Friday.

The application says “several of the existing mature trees” on the 0.9-acre property will be preserved to screen the tank from other residences, supplemented by new deciduous and evergreen trees and shrubs and a 7-foot-tall fence around the perimeter.

In addition to replacing and upgrading the water tank, Fairfax Water plans to install new transmission water mains along neighboring streets to connect the facility to the existing system, according to the project page.

After holding public outreach meetings on the project last year, the authority doesn’t anticipate starting construction on the tank until the second quarter of 2025.

The application for a special exception and 2232 review — which determines whether a public facility is compatible with the proposed site — is currently being reviewed for acceptance by county staff.