Lake Accotink Dredging (AC89-0009)

Project Background

Lake Accotink was constructed by the United States Army in 1940 as a freshwater supply for Camp Henderson (now Fort Belvoir). Intense development in the 30 square mile watershed draining to the lake following World War II resulted in the lake losing 50 percent of its capacity. The US Army dredged the lake prior to transferring it to Fairfax County in 1967. A second wave of development in the 1960s and 1970s added significant sediment to the lake. The Fairfax County Park Authority (FCPA) conducted a study in 1982 showing that the lake volume had been reduced to about 25 percent of its original compacity. The FCPA dredged the lake to restore capacity in 1985. By 2001 the lake had filled up again with sediment at a rate of more than 17,000 cubic yards per year. The Fairfax County Department of Public Works and Environmental Services (DPWES) partnered with FCPA to dredge the lake again in 2008. Analysis in 2016 estimated that the lake is now filling up again at about 23,000 cubic yards of sediment per year.

The project will also help the county meet is MS4 permit requirements. The Virginia Department of Environmental Quality (DEQ) issued a sediment total maximum daily load (TMDL) for the Accotink Creek Watershed in August 2017. Wasteload allocations to Fairfax County under the Accotink Creek TMDL assume different loading rates upstream and downstream of Lake Accotink. Additionally, the US Environmental Protection Agency’s model for the Chesapeake Bay includes Lake Accotink and assumes that a relative trapping efficiency of about 50 percent for the lake will be maintained by Fairfax County to prevent increases in sediment entering the bay.

Project Description

The Lake Accotink dredging project will remove an estimated 350,000 cubic yards of sediment to reestablish lake depth and put in place a maintenance dredging program to sustain water quality in Accotink Creek and aesthetic and recreational benefits for county residents.

Project Location

The project is in the Braddock Magisterial District in Lake Accotink and Wakefield Parks in the Accotink Creek Watershed.

Project Phase

The project is in the field condition assessment phase which will result in development of an alternatives analysis to guide how to implement dredging.

Timeline

What To Expect

Field studies, plan development and public meetings will take place through 2022. Dredging will start in 2022 and run through late 2025. When construction occurs, there will be truck traffic to the project sites, a temporary pipeline running between Lake Accotink and Wakefield Park, dredging equipment operating in Lake Accotink and spoils processing operations in Wakefield Park. Residents should expect dump trucks moving to and from Wakefield Park via Braddock Road to remove dredged sediments throughout the week starting after 7 a.m. on weekdays. Note that at some periods during construction, work may occur on weekends. Activities on those days will begin after 9 a.m.

Project cost and funding source

Construction costs for the Lake Accotink Dredging project will ultimately be paid for by the county’s Stormwater Service District.

Presentations to the community

For more information, please visit the following:

• Lake Accotink Dredging Project Overview Zoom Meeting: December 10, 2020 (video)
• Lake Accotink Dredging Public Meeting December 2020
• Arcadis Design and Consultancy Lake Accotink Dredging Public Meeting Dec 2020
• Lake Accotink Sustainability Plan
• Lake Accotink Sustainability Update September 2019
• Lake Accotink Master Plan Revision

Contact

For more information please email Project Manager Charles Smith, Stormwater Planning Division, Department of Public Works and Environmental Services, or call 703-324-2467, TTY 711.