Springfield’s Lake Accotink shouldn’t be dredged, but allowed to become a wetland, report says

Fairfax County staff is now recommending that Lake Accotink in Springfield not be dredged, but instead allowed to naturally develop into a wetland.

New findings released by the county late last week concluded that dredging the 55-acre man-made lake is no longer the best option “due to…significant community and environmental impacts and excessive costs.”

The hope was to restore the lake to its original condition, but there’s 43% more sediment in the lake than estimated in 2018. That sediment would require more frequent dredging, increasing costs and the number of truck trips to haul it away.

The price tag was estimated at $95 million to dredge the lake, plus an additional $300 million over the next 20 years for maintenance, per the analysis. That would have brought the total to nearly $400 million.

Instead, the staff is recommending restarting the Lake Accotink Park Master Planning process this spring or summer, with the expectation that the “changing conditions of the lake” will eventually turn it into a “maintained wetland and/or floodplain forest complex.” That could happen in the next few years.

A virtual public meeting will be held tonight at 7 p.m., with an in-person public meeting set for tomorrow (Thursday) at Kings Glen Elementary School to allow residents to weigh in on this new plan.

This conclusion may come as a surprise to some, considering it was just in 2019 when a plan to dredge Lake Accotink was endorsed by the Board of Supervisors.

But in just a few years, the lake and surrounding circumstances have changed enough to no longer make that feasible, according to the report.

The lake now has 500,000 cubic feet of sediment, compared to 350,000 previously. At that rate of build-up, it’s estimated that dredging would have to happen every five years. Transporting and disposing of the sediment would require 15,000 truck trips each time on area roads and through neighborhoods.

The place initially discussed as a drop-off point — Wakefield Park Maintenance Facility near the powerline easements — is no longer available due to infrastructure now there.

Additionally, all the work and maintenance needed would have greatly impacted the surrounding 482-acre park, making it far less accessible, useable, and easily enjoyed by the public.

The report argues that dredging Lake Accotink is ultimately a much less preferable option than simply letting it eventually become a maintained wetland.

Lake Accotink was first built in 1940 by the U.S. Army as a freshwater reservoir for what was then called Camp Humphries, now Fort Belvoir. But “intense development” around the lake and in its watershed led to its shrinking and continued issues today.

By 1982, Lake Accotink had shrunk to only 25% of its original capacity. The county kept dredging the lake, but those dredgings became more frequent.

The report blames the deteriorating conditions of the lake on development as well as climate change.

“The condition of Lake Accotink today is largely due to rapid development within the Accotink Creek watershed in the mid-20th century, which resulted in increased stormwater runoff that eroded streams and sent large amounts of sediment into the US Army drinking water reservoir that became Lake Accotink,” it reads.

In a newsletter last week, Braddock District Supervisor James Walkinshaw, who represents the lake area, said it might be a “shock” to hear these findings, but this is the best path forward, particularly considering the impact the constant dredging would have on the park.

“The initial three to five year base dredge and subsequent year-long maintenance dredges conducted every five years mean that the park and surrounding community would endure significantly more disruption than originally anticipated,” Walkinshaw wrote. “I know I and my colleagues are disappointed in this result as our first choice has always been to restore the lake to as close as possible to its original condition.”

The report includes renderings and mock-ups of what the lake, park, and facilities could look like when it becomes a fully developed wetland.

“Environmental restoration is a continual process, and all other features of the park will capitalize on this renewed environmental focus. Wetland development will create habitat for a more diverse group of bird species, promoting conditions to support wetland breeding birds and wading birds,” it reads. “The future park would benefit more than just wildlife. It would be an important place for humans seeking peace, refuge, and a respite from the concrete jungle.”