Christopher S. Herrington,
FEBRUARY 10, 2021: The design consultant, Michael Baker International, is currently working on the 50 and 70% design, which include identification of necessary temporary construction and permanent sanitary force main easements, initiation of land acquisition to obtain easement rights, geotechnical investigation, subsurface utility test pits, and obtaining the necessary regulatory permits. Prequalification of contractors will also occur during the Design Phase. The 50% design will be presented to the Wessynton and Surrey HOA board members once it is complete and ready for presentation.
The Little Hunting Creek Force Main consists of 30-inch diameter prestressed concrete cylinder pipe (PCCP) and ductile iron pipe (DIP), constructed in the mid-1970s. It conveys wastewater (generated from sinks, laundry machines, showers/tubs, and toilets) through a gravity collection and force main system and on to a treatment plant for processing. This force main runs beneath Little Hunting Creek and through residential property from the Little Hunting Creek Pump Station near the intersection of Thomas J. Stockton Parkway and Londonderry Road, to a junction discharge chamber near the intersection of Surrey Drive and Surrey Court. The total length of force main to be replaced is approximately 4,560 feet (as shown below).
The Fairfax County Department of Public Works and Environmental Services (DPWES) previously performed a condition assessment of the force main, which resulted in the need for two external repairs which were performed during 2016. Due to its age, and as a result of findings during the assessment, it was determined the existing aged force main is nearing the end of its useful and practical life and needs to be replaced.
A study was recently conducted to investigate options for replacing the existing force main. The location of the force main, within a tidal creek and across residential properties, presents challenges to typical construction methods. Such challenges include installation means and methods; staging and storage of materials; environmental regulatory considerations, potential time of year restrictions for site access; potential damage to the existing force main and adjacent utilities; impacts to private property; maintenance of traffic and accessibility to residences; and, future operations and maintenance considerations.
After considering nine potential alternatives, evaluated as part of a Basis of Design report, the recommended alternatives (shown in green below) minimize environmental concerns; minimize impacts to private properties, provide for potential nature trail improvements or amenities; and provide greater accessibility for future operations and maintenance efforts. The recommended alternative is based on preliminary engineering efforts and may be adjusted during the design stage based on actual field surveyed conditions.
Located within the Mount Vernon District, the force main runs beneath Little Hunting Creek and through residential property from the Little Hunting Creek Pump Station near the intersection of Thomas J. Stockton Parkway and Londonderry Road (to the east), to a junction discharge chamber near the intersection of Surrey Drive and Surrey Court (to the west). The project corridor is located across Sanitary Sewer Map Tiles 101-4, 102-3, 110-2 and 111-1, as shown below.
It is expected the new force main will serve the surrounding community for at least the next 50 years. Replacement of the Little Hunting Creek Force Main will:
The Preliminary Design Phase was completed in April 2020. Topographic survey and subsurface utility designation work were completed in June 2020. The project is currently in the Design Phase. Design efforts are currently anticipated to be completed in late autumn 2021. The start of the site work associated with the Construction Phase is dependent on the completion of the adjacent Little Hunting Creek Sanitary Sewer Replacement Project. At this time, Construction is currently expected to commence in mid-2022 and is expected to take approximately 16 months to complete.
This project will be awarded to a qualified contractor through a competitive bidding process once design efforts are completed. Potential staging areas and access points off-site will be studied. All work will be supervised by Fairfax County staff. Every effort will be made to minimize disturbances and impacts to public and private areas. Careful consideration will be given to schedule construction activities to minimize interference with recreational activities. There will be no interruption to existing sanitary sewer service.
The planning level cost estimate for replacement of the Little Hunting Creek Force Main is approximately $10 million. This cost is funded solely from fees billed to residents for use of the sanitary sewer system, and is not tax based.
The project was presented during community meetings held: on November 19, 2019 at Mount Vernon High School; and, on December 5, 2019 at the Gerry Hyland Government Center.
The county anticipates having an additional public meeting as the design progresses, to provide additional and updated information regarding construction related activities and anticipated timeframes.
For questions about the project, or to be added to our distribution list to receive project updates as they become available, please contact Natasha Schmidt, Fairfax County’s project manager, at 703-324-5080 (TTY 711) or by email at firstname.lastname@example.org.
12000 Government Center Pkwy
Fairfax, VA 22035