Lake Accotink task force finds lake could be partially saved with regular dredging

The best path forward for saving Lake Accotink might to let it shrink, a Fairfax County task force has proposed.

Created by the Fairfax County Board of Supervisors in May, the 30-person group was charged with exploring alternatives to fully dredging the sediment that has accumulated in the man-made body of water or converting it to a wetland, as recommended earlier this year by county staff.

In a final report delivered to the board yesterday (Tuesday), the Task Force on the Future of Lake Accotink suggested that 20 to 40 acres of the lake could be preserved with “a program of regular maintenance dredging,” which would allow kayaking and other water recreation to continue at the popular Springfield park.

The remainder of the lake could be turned into “some combination of a managed wetland and a grassland,” the task force proposed. Originally 110 acres in size, Lake Accotink has already been reduced to 49 acres, thanks to sediment build-up from the area’s development, the report says, citing Fairfax County Park Authority project manager and senior planner Adam Wynn.

“There is no doubt that preserving a smaller lake meets significant community and social goals,” a task force subcommittee charged with analyzing alternatives to a full dredging wrote in the report. “Even a small lake would allow the maintenance of the current marina area, a community gathering place for picnics, birthday parties, and many others who enjoy the calming effects of a lake environment. And, importantly, a small lake would still preserve the beauty that so many find in a lake for generations to come.”

Frequented by over 250,000 visitors a year, Lake Accotink Park (7500 Accotink Park Road) is one of the park authority’s top attractions. It features miles of trails, a carousel, a mini golf course, a picnic area, bicycle rentals and a recently updated playground in addition to a marina, where visitors can rent canoes, kayaks and paddle boats.

However, sediment carried into the lake by Accotink Creek needs to be periodically dredged, a process undertaken in 1985 and 2008. The Board of Supervisors approved a plan in 2019 to conduct an initial $30.5 million dredging operation, followed by annual maintenance dredges that would cost an estimated $2 million per year.

But the Fairfax County Department of Public Works and Environmental Services (DPWES) and its consultant, Arcadis, reported in February that 43% more sediment would need to be removed than initially estimated, and the costs of both the initial dredgings had skyrocketed to roughly $95 million.

The first 20 years of the annual dredging program would require an additional $300 million in funding, according to the February report, which was based on data collected since 2021.

As a result, DPWES staff recommended letting the lake fill up and revisiting the park’s master plan to determine how it might be maintained in the future as a “wetland and/or floodplain forest complex” — a proposal that alarmed community members.

“It was a difficult recommendation for the community to hear, and it was met with anger, with frustration, with disappointment,” said former Board of Supervisors chair Sharon Bulova, who was appointed chair of the task force when the board voted to establish it on May 23.

Bulova was joined on the task force by former Braddock District supervisor John Cook, Del. Vivian Watts (D-39), residents, and representatives of civic associations, nonprofits and other community groups. Assisted by county staff and a new consulting team from WSP-LimnoTech, the task force held 30 meetings in all, nine as a full group and 21 in subcommittees.

In addition to evaluating options for the lake’s future, the task force made a case for its value as a natural and community resource, a step some felt was “conspiciously missing” from the DPWES analysis. The staff recommendation was evaluated by another subcommittee, which noted that the initial report didn’t include details about how the new cost estimates were determined.

According to the new report, the task force explored three options for downsizing Lake Accotink:

1. A roughly 41-acre lake extending from the marina to the “big island” at the northern end of the lake. It would cost an estimated $34 million to dredge the approximately 9 million cubic feet of sediment required to maintain a depth of 8 feet.
2. A 22-acre lake that would require a dredge of about 3.9 million cubic feet, costing an estimated $24 million
3. A 33-acre lake with a grassland built on sediment dredged from the lake and deposited in its footprint

The grassland option would restore a habitat that was abundant in Northern Virginia prior to European settlements and farming, and it could “combine with the existing wetland and an open water feature of increased depth to create the most beneficial environment,” the report says.

The “alternatives” subcommittee notes that county staff had proposed creating an “offline” lake separate from the main Accotink Creek channel, but the group decided that was “not a viable option as it does not serve the greater purposes of the lake.” WSP-LimnoTech had said an offline lake would be susceptible to algae blooms, which regularly plague Reston’s lakes.

Bulova described working on the task force as a rewarding experience, where everyone showed up willing to collaborate.

“Never underestimate the value of community engagement,” she told the Board of Supervisors yesterday. “Even if it’s a difficult subject matter, people are willing and want to participate and want to have a seat at the table.”

Braddock District Supervisor James Walkinshaw, who represents the Lake Accotink area, stressed that the task force’s findings are not intended to be a decisive recommendation for what the county should do.

“But they’ve given us some very valuable insight into ways we can improve the process moving forward,” Walkinshaw said, calling the uncertainty about Lake Accotink’s future “one of the most challenging issues I think we’ve faced in a long time.”

The board agreed to discuss the report in more detail at its environmental committee meeting next week on Tuesday, Dec. 12.