A cherished Virginia lake losing its long battle against urban runoff

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Lake Accotink has long been a cherished oasis amid Northern Virginia’s busy streets, one dredged three times since 1965 to keep silty urban runoff from swallowing it up.

With a warming climate making heavy rains more frequent and the increasing runoff damaging waterways across the Chesapeake Bay region, local officials now are ready to give up on the idea of Lake Accotink being a lake.

Due to the arriving sediment, the 105-year-old human-made body of water is nowhere near the eight-foot depth it was when it was last dredged in 2008, Fairfax County public works officials say. In some portions away from the shore, seagulls are able to stand with just their feet getting wet.

The public works department says another planned dredge, approved by the county board in 2019, should not go forward, because it would be too expensive and might cause more environmental harm than good with all the truck trips required to clear out the waste again and again in coming years.

“It’s kind of like digging a hole in the beach when the waves are coming in,” said Charles Smith, who oversees watershed projects for the county’s public works department.

The department’s recommendation to the county board that the lake be allowed to become a semiaquatic wetland has stirred anger among Springfield-area residents who have enjoyed it as a recreation hub.

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On a sunny weekend day, the county park that surrounds the lake fills with the sounds of all-day picnics, outdoor concerts and nature enthusiasts looking for bald eagles or otters — a mix of people of all incomes and backgrounds that reflects the broader population.

But, like the rest of the Washington region, the community is facing the result of decades of development that often did not have adequate storm-water controls or preserve enough open space to serve as buffers against storm runoff, county officials say.

“This is why we have the sediment,” C. Greg Carroll, 67, who has lived near the lake since 2004, said at a recent crowded town hall meeting about Lake Accotink’s future. “We’ve got to live more compactly. It is a disgrace that we haven’t saved more open space and more farmland.”

Lake Accotink was created in 1918, when the federal government constructed a dam along the Accotink Creek watershed to store drinking water for what is now Fort Belvoir.

By the late 1950s, the water was no longer suitable for drinking and, in 1964, half of it was filled with debris and silt flowing in from the nearby subdivisions that sprang up during a massive population boom in Fairfax County.

The U.S. Army Corps of Engineers dredged Lake Accotink in 1965. Then, the federal government sold it, the dam and what would become parkland surrounding it to Fairfax County’s Park Authority, when about 101,000 visitors were already picnicking or fishing there every year.

Five years later, the lake was so polluted that the county closed it to recreational activities and launched plans to drain, clean and refill it — allowing it to reopen for boating and fishing the following summer.

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So began a cycle of lake maintenance, mostly through dredging, that became increasingly complicated as Northern Virginia grew into a suburban metropolis of planned communities, business districts and shopping plazas — all with roads and other impervious surfaces channeling storm runoff into surrounding lakes and streams.

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Another dredge occurred in 1984 and again in 2008. In between were 5K races around the water, carousel rides near the beach and leisurely boat trips, before the reaccumulating mud banks got too high for some larger boats.

In 2019, when the amount of incoming sediment settling in the lake had increased to nearly 20,000 cubic yards per year, the county and area residents agreed on what they thought would be a permanent solution. They developed a plan to dredge 350,000 cubic yards, bringing the lake’s depth back to eight feet, with other dredges to take place in subsequent years.

The county estimated that initial dredge would cost about $30 million, a sum the Board of Supervisors readily agreed to finance through a state revolving loan fund for clean-water projects.

The strategy would allow the county to “really ensure that we’re going to save Lake Accotink,” then-board Chair Sharon Bulova (D) said before the unanimous vote.

Nearly four years later, the public works department concluded that a variety of previously unknown factors would drive up the cost.

First, the county isn’t allowed to use a Dominion Energy power line easement in Wakefield Park, north of the lake, as a free staging ground for the sediment to dry out before being hauled away, as was earlier believed. After consulting with Dominion, the county learned that the sediment would block the power lines in the event of an emergency and that the area is in a flood plain, department officials said.

That makes it necessary to use another site, probably in the same park, that would require about seven acres of trees to be cleared away to make room for the staging.

Also, about 150,000 cubic yards more sediment than initially expected would have to be removed to get to the desired depth of eight feet at the end of the project’s three-year period — in total, enough silty waste to fill a football field to a height of more than 200 feet.

Finally, the project would mean as many as 50,000 truck trips through the area, potentially through some neighborhoods, with smaller “maintenance” dredge projects needed every five years, the county said.

The estimated cost of the first dredge escalated to $95 million, with another $300 million required to keep the lake intact over a 20-year period alone, the public works department said.

“That is money that would not be available to reduce flood risks for thousands of residents whose homes are experiencing flooding today,” Chris Herrington, the department’s director, told the town hall meeting crowd. “That is money that will not be available for stream restoration or for us to build any other important county project that the county would otherwise want.”

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The decision over what to do next lies with the Board of Supervisors.

But the prospect of asking Fairfax taxpayers to shoulder the approximately $400 million cost — through a larger state loan or a bond issuance that would hurt the county’s ability to finance other projects — is not appealing, several supervisors said.

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“Right now, the prognosis for this project is not good,” said Supervisor James R. Walkinshaw (D-Braddock), whose district includes a large portion of Lake Accotink. He added that he nonetheless hasn’t given up hope on what he called an “agonizing” situation.

Gail Nittle has lived across the street from the Accotink Park for 40 years. The head of the Springfield Civic Association, Nittle, 76, sees Lake Accotink as a leveling force in a steadily changing community of various incomes, where someone without many resources can enjoy the same free amenity as everyone else.

“If we’re really concerned about social equity, why not allow them to keep the one enjoyment that they can walk to?” Nittle said. “They can do the canoes, they can kayak, they can fish. Though, I wouldn’t recommend eating those fish.”

Allan Robertson, who co-founded Save Lake Accotink, a community group instrumental in formulating the 2019 dredging plan, said he believes the county has long wanted to abandon the lake. During initial conversations about the 2019 dredging plan, the county said the influx of sediment is too great, Robertson said.

“What is absolutely clear is that, in 2018, the only choice the county wanted was to let the lake fill in,” Robertson said. “In 2023, the only choice they want is to fill the lake in. There are no dots to connect there. It’s the same dot.”

Former local supervisor John C. Cook (R-Braddock) agreed and accused the public works department of “fearmongering” by suggesting the surrounding neighborhoods would be inundated by truck traffic if the dredge occurs. The community and county had already agreed that the 2019 dredging plan would involve staging most of the sediment in Wakefield Park, where Interstate 495 is a short drive away, Cook said.

He suggested any effects would be reduced by stretching out the dredge period, so less sediment needs to be hauled away every year — an idea the county says wouldn’t make much of a dent because of the massive amounts coming in.

Cook also argued that the potential environmental effects, through truck trips and tree clearing, would not be as great as the public works department suggests.

“We cut down five acres of trees for other development projects; hell, it’s done all the time,” he said. “Braddock Road itself takes 70,000 cars per day. These trucks, yes, they’re dirty. But they’re not going to appreciatively affect the environment any more than the additional car traffic that comes with normal growth.”

The storm runoff from developed surfaces has polluted the Chesapeake Bay, killing aquatic life, leading to federal requirements for states and local governments to restore streams whose banks are eroding under the pressure.

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Fairfax County has several such multimillion-dollar projects underway, including some along Accotink Creek, upstream from the lake, that are aimed at reducing sediment, salinity and other pollutants flowing south.

But the benefits of those projects are years away, with the continuing runoff rushing in sometimes redamaging areas that were previously restored.

“They’re not just healthy systems that are operating under normal, healthy conditions,” said Joe Wood, a senior scientist for the Chesapeake Bay Foundation focusing on Virginia. “They are systems that are being flooded with high volumes of erosion and high volumes of storm water. You have to keep investing and taking care of these waterways that have been so disturbed.”

That reality complicates the question over what to do about Lake Accotink.

County public works officials say that allowing a wetland to form where the lake sits — something that would gradually happen over an unknown number of years should dredging stop — would result in more ecological diversity to the area.

New plants there could trap the incoming sediment before it ultimately flows downstream into the Potomac River, though not all of it, the department said.

The cost of any additional stream repair work downstream required because of that escaping sediment would be “nowhere near” the cost of dredging, said Smith, the wetland projects manager.

But it’s unclear what that wetland would ultimately look like, given the magnitude of sediment coming in, said Jeffrey C. McKay (D-At Large), chairman of the county board, adding that he wants the county to commission a study to find out the answer before the lake’s fate is decided.

If it becomes a functioning wetland, akin to Huntley Meadows Park about 11 miles away, the county could develop a plan to maintain that as a new main feature of the park, McKay said. “That’s a different story than what it would look like if, in fact, it just became overrun as an uncontrolled sediment dump,” he said. “That’s what we need to figure out.”

On the other hand, “the idea that we’re going to have to go in there every five years in perpetuity? That’s the part that’s really concerning,” McKay said. “This is a situation where there is really not a good answer.”

As the community waits for the county board to decide the lake’s fate, those who visit take in the view — knowing that it may one day be gone.

On a recent morning, Jaime Morán, his wife, Isabél, and their 5-year-old son stood alone on the lake’s beach, feeding some geese as a blanket of fog over the water partially obscured the towering pine trees and dam in the distance.

The couple said they have visited the lake since 1998, picnicking or walking the lake’s perimeter, where they’ve spotted water snakes and raccoons.

“They should do what they can to save it; it’s not just us human beings. The animals here also depend on this space,” Jaime Morán said in Spanish, standing near a cluster of branches, plastic water bottles and other debris that had made their way to the lake’s edge.

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