Reston Association had hoped to dredge sediment from Lake Thoreau this fall, but paltry precipitation may force the project to wait until next spring.
While staff still hope to schedule the dredging for sometime this winter, the rain and snow that passed through the D.C. region last week weren’t enough to sufficiently raise water levels at the manmade lake, according to RA communications director Cara O’Donnell.
“Lake levels need to rise in order to safely bring equipment on to the lake,” O’Donnell said.
Based on a survey conducted last year and a “visual inspection,” a contractor hired by RA estimates that it will need to remove 1,200 cubic yards of sediment from the Westcove area to restore Lake Thoreau to its original design.
Created in 1971, Lake Thoreau has a surface area of 46.2 acres and an average depth of 20.3 feet, though its deepest point extends down 38 feet, according to a February 2025 water quality report that reviewed all four of RA’s lakes.
Like other manmade lakes, Thoreau fills up with sediment that accumulates from the surrounding watershed and needs to be dredged regularly. RA dredged the Lake Anne canal this spring, a process that started in early April and concluded in May.
“Regular maintenance allows for important stormwater storage and filtration that protects downstream waterways. It also ensures boats can navigate through the waters,” RA says on its project page. “The sediments that accumulate in our lakes are rich in phosphorus, which have the potential to fuel algae blooms.”
If accumulated sediment isn’t cleared, lakes could disappear — a prospect currently threatening Lake Accotink in Springfield, as Fairfax County staff continue reviewing the feasibility of preserving the lake as a smaller body of water.
Because a sanitary sewer line cuts across the Westcove area slated for dredging, RA wants to ensure that the lake’s water levels are high enough to allow the barges that will carry the removed sediment, Austin Mayhew, capital projects manager for the homeowners’ association, said in a Nov. 21 update.
“We hope this project can kick off this winter, but if we don’t get the rain, we’ll likely kick the project off in the spring,” Mayhew said.
According to the Virginia Department of Environmental Quality, Northern Virginia, including Fairfax County, has been under a drought watch since Sept. 22, with groundwater at “emergency” levels. The Virginia Drought Monitoring Task Force is next scheduled to meet on Dec. 16 to review current conditions.
Once the Westcove dredging project kicks off, RA says operations will take three to four weeks. During that time, the pathway connecting South Lakes Shopping Center and Ridge Heights Road will be closed, since the contractor will stage equipment on the South Lakes side of Lake Thoreau.
In other Reston capital projects news, RA is nearing completion of the first phase of upgrades at the Hook Road Recreation Area located southeast of the Fairway Drive and Hook Road intersection.
“There are minor outstanding items that will be complete before spring ’26,” O’Donnell said.
Under construction since August, the project’s first phase includes updated backstops, fencing and dugout areas for the baseball diamond, along with new water fountains and concrete walking paths.
However, it might be some time before RA gets to the project’s second phase, which will complete the walking path and install permanent restrooms. The association’s Board of Directors approved a 2026 budget in November that delays funding for those additional renovations to 2027.
