The projects would address pollution, sedimentation, and other issues caused by erosion, increased runoff, and changes in stream flow caused by development and urbanization.
The Accotink Creek watershed encompasses 51 square miles, making it the second largest watershed in Fairfax County. Thirty percent of the watershed is “impervious,” which refers to land surface covered by roads, parking lots, driveways, and rooftops that prevent rainfall from infiltrating into the soil. When too much of the land is impervious, there is an increase in erosion and sedimentation, factors that contribute to pollution and degrade water quality and wildlife habitat.
The final plan must be approved by the Board of Supervisors. The public can submit comments on the draft online by Oct 21. The Watershed Advisory Group, made up of local stakeholders, advised the planning team about community outreach opportunities, key issues affecting the watersheds, and potential projects.
Among the proposed projects in Annandale are the following:
- Behind the 800 block of Braddock Road in Wakefield Park - $1.44 million to restore two existing stream channels, reconnect them to the floodplain and install grade controls to help prevent further erosion.
- 4200-4300 block of Elizabeth Lane - $754,000 to stabilize a storm drain outfall from Elizabeth Lane and a tributary channel that leads to two storm drain outfalls off Ossian Hall Lane.
- 4200-4300 blocks of Ann Fitz Hugh Drive - $1.01 million to reconnect the upstream and downstream portions of a stream to the original floodplain and install grade controls to help prevent future downcutting and overwidening, reduce the existing channel dimensions, raise the bed elevation of the channel, and correct the slope of the channel at the sewer casing.
- 4200 block of Woodlark Drive - $621,000 to restore the channel, focusing on regrading and stabilizing eroded stream banks with armor-in-place or bioengineering techniques and raising the current bed elevation of the channel to the stream culvert under Woodlark Drive.
- 8220 Little River Turnpike near Calvary Church of the Nazarene - $344,000 to restore and regrade the channel and stabilize eroded stream banks with armor-in-place and bioengineering techniques.
- 4300 block of Americana Drive - $811,000 to reduce erosion on two existing stream channels located within a private apartment complex between Americana Drive and Donnybrook Court.
- 4200 block of Americana Drive - $903,000 for stream restoration focusing on reconnecting higher flows back to the original floodplain to dissipate energy and encourage deposition of sediment on the floodplain.
- 3401 Woodburn Road - $1.664 million to restore two existing stream channels and a ditch in Pine Ridge Park and an existing stream channel in Accotink Stream Valley Park.
- Intersection of Glen Park Road and Braddock Road - $569,000 for a new pond and berm.
- Intersection of Americana Drive and Commons Drive - $86,000 for a pond retrofitting.
- South of the intersection of Frost Way and Whitman Road - $384,000 for pond retrofitting, a new riser, and tree removal.
- Between the 7700 block of Donnybrook Court and the 4300 block of Americana Drive - $187,000 to convert an existing in-stream pond to a shallow wetland.
- Intersection of Championship Drive and Championship Court - $74,000 to convert a dry pond to an extended water detention facility.
- 3719 Mount Airey Lane in Lafayette Village - $97,000 to convert a dry pond to an extended detention facility by modifying the riser structure.
- 7820 Libeau Lane - $988,000 to create a new pond.
- 8900 Little River Turnpike, behind the Jewish Community Center - $71,000 to convert a dry pond to an extended detention facility, modify the riser structure, and replace the flow channels.
- 3400 block of Monarch Lane - $163,000 for a pond retrofit.
- Intersection of Monarch Lane and Happy Heart Lane - $436,000 to convert a dry pond to a wetland facility.
Areawide drainage projects
- Ravensworth neighborhood - $365,000 to install tree box filters at various inlets.
- 4910 Willet Drive at Canterbury Woods Elementary School - $44,000 to install two tree box filters in catch basins to the west of the school’s parking lot.
- 4606 Ordinary Court in Wakefield Chapel Estates - $188,000 to install a vegetated swale with check dams to treat runoff flowing behind two homes.
- 4400 Duncan Drive in Wakefield Chapel Park - $251,000 to install a bioretention filter to replace the existing channel.
- 4001 Wakefield Chapel Road - $388,000 to convert three lot dry ponds at the Northern Virginia Community College parking lot to bioretention filters.
- 7604 Herald St. - $118,000 to install two bioretention basins and three tree box filters to treat runoff from the Annandale Terrace Elementary School parking lot.
- 7450 Little River Turnike - $99,000 to install bioretention filters to treat runoff from the Little River Shopping Center.
- 8100 Guinevere Drive and 3401 Woodburn Road - $124,000 to install a bioretention filter to treat the runoff from a parking lot and tennis courts at Camelot Elementary School.
- 8515 Tobin Road and 3406 Woodburn Road - $78,000 to install a bioretention basin to treat runoff from a parking lot in Eakin Park.