Project Update: April 17, 2024

Following Board of Supervisors (Board) approval of the formation of the Task Force on the Future of Lake Accotink in May 2023, the Task Force reviewed past dredging studies and county staff recommendations to ensure that all options have been considered to preserve Lake Accotink in the most sustainable, equitable, and cost effective manner. The Task Force concluded its work and reported its findings to the Board on December 12, 2023. Task Force meetings, video recordings and meeting minutes can be found at Task Force Meeting/Materials Archive. Task Force’s report is located at Lake Accotink Findings Report.

On January 23, 2024, the Board approved Task Force’s findings which provided a path forward that has the potential to preserve Lake Accotink for generations to come. This path forward also revealed the need for additional study and analyses of various options identified for long-term preservation of Lake Accotink.

Therefore, the Department of Public Works and Environmental Services (DPWES) Lake Accotink project team, in cooperation with Fairfax County Park Authority (FCPA), is moving forward with four concurrent efforts to support the Lake Accotink project. These include a sedimentation study, dam assessment (dam is owned by FCPA but assessment will be supported by DPWES), feasibility study for a smaller lake option as identified in the Task Force’s findings and a community engagement plan.

The Lake Accotink team is committed to having a robust and inclusive public outreach and engagement plan for the project, to include increased transparency during the project phase. The team has already begun efforts to identify an experienced community engagement consultant to serve as neutral facilitator that supports opportunities to enhance outreach and engagement.

Comments on Lake Accotink Analysis and Feasibility Study

We value your comments and input. Information submitted will be compiled and used by Fairfax County to improve the Lake Accotink Analysis and Feasibility Study. Comments can be submitted via email to the project manager Turgay.Dabak@fairfaxcounty.gov, or by US Mail to Fairfax County DPWES – Lake Accotink Dredging, 12000 Government Center Parkway, Suite 449, Fairfax, VA 22035.

Project Background

Lake Accotink was constructed by the United States Army in 1940 as a freshwater supply for Camp Humphreys (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. This was due to continued development in the watershed, mostly prior to the issuance of stormwater management regulations, which increased overland runoff eventually causing streambank erosion and contributed significant amount of sediment to the lake. 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 capacity. 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 its MS4 permit requirements. The Virginia Department of Environmental Quality 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

As approved by the Board on January 23, 2024, DPWES and FCPA will move forward with Task Force’s findings which identified additional studies and analyses of various options identified for long-term preservation of Lake Accotink. This mainly includes dredging and maintaining a smaller lake, use of dredged material on-site, and creating a wetland and grassland area. These alternatives will be evaluated in a feasibility study and community input. A timeline of these additional studies and the feasibility study will be provided by Summer of 2024.

Project Location

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

What To Expect

Field studies, stream sediment and flow measurements, dam assessment and public outreach will take place through 2022 as soon as consultant scopes are developed and approved by mid-2024. Dredge design and permitting will start after the completion of the feasibility study and the selection of the preferred alternative.

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.

For more information, please visit the following:

• Task Force Lake Accotink Findings Report
• Task Force Meeting/Materials Archive
• Lake Accotink Dredging - Results from April, 2023, Community Survey
• Lake Accotink Dredging Program Review, February 2023 (Video) | Presentation Slides
• Lake Accotink Dredging Public Meeting February 10, 2022 (Video) | Presentation Slides
• Lake Accotink Dredging Project Overview Zoom Meeting: December 10, 2020 (video)
• Lake Accotink Sustainability Plan
• Lake Accotink Sustainability Update September 2019
• Lake Accotink Master Plan Revision
• Alternative Evaluation - July 29 and August 5, 2021
• Alternative Analysis Report Lake Accotink Dredging Project December 23, 2021
• Project Update Meeting - February 10, 2022
• Dredge Program Cost Summary
• Offline Lake Construction Cost Summary

Contact

For more information, please email Project Manager Turgay Dabak, Stormwater Planning Division, Department of Public Works and Environmental Services, or call 703-877-2809, TTY 711.