A community meeting was held on January 28, 2021 to review the conceptual design.
The project was identified for stream restoration and stabilization activities in the Fiscal Year 2020 work plan. The project is in wooded, residential neighborhoods. The stream channel exhibits eroded and over-widened banks, head-cuts and the potential for further bed and bank instability. A sanitary sewer line is exposed within the Rocky Run channel.
The project area is generally identified as a floodplain and Resource Protection Area. The project will restore approximately 3,430 linear feet of degraded natural channel of Rocky Run Branch between Hunter Mill Road and Hill Road and approximately 1,740 linear feet of outfall channel in Ashlawn Park. The project area stream drains about 773 acres of surrounding neighborhoods that includes most of the Oakton Shopping Center. Restoration objectives include stream stabilization, water quality improvement, aquatic and riparian habitat enhancement, and reconnection of the channel with its floodplain. It is anticipated that the restoration will provide additional biological improvements with habitat features introduced to the restored stream channel and native vegetation plantings along the riparian corridor. Stormwater Planning Division staff will coordinate stream restoration design plans with the Fairfax County Maintenance and Stormwater Management Division in their efforts to repair a culvert located at Hickory Hollow Lane.
The stream restoration project is located along the main channel of Rocky Branch between the headwaters near Hill Road to the culvert at Hunter Mill Road. The tributary portion of the project traverses through Ashlawn Park from the outfall at Nadine Drive to upstream of an existing pond.
The project is in the Providence District and in the Difficult Run Watershed.
Restoration of the ecological function of the stream corridor
Creation of a safe and sustainable stream valley for the community
Protection of surface waters, private property and county infrastructure
Restoration of native vegetation and plant diversity
Improvement in water quality by removing Nitrogen, Phosphorous and Total Suspended Solids
Improvement of habitat for wildlife
The project is in the design phase.
Preliminary design: April 2021
What to Expect
Over the next several months, the design team will be walking the project area and verifying the concept design. County staff will be in contact with the homeowners where easements are required to construct the project.
Project Cost and Funding Source
Restoring the section of Rocky Run as part of this project is estimated to cost $9.3 million. Stormwater projects are funded through the county Stormwater Service District.
Presentations to the Community
Public meetings for the project will be scheduled online due to Covid-19 restrictions. Notifications about upcoming meetings will be sent to the Homeowner Associations and owners who are adjacent to the project area.