Wastewater FAQ

Wastewater management focuses on the proper collection, treatment and discharge of domestic wastes from households and industries, in order to clean, protect the public health and minimize adverse environmental effects on the Potomac River and its tributaries. Wastewater from households and industries is collected in sanitary sewers, and usually treated at one of the treatment plants in our region. After treatment, the wastewater is discharged to a tributary of the Potomac River.

Fairfax Water and Town of Vienna provide this combined bill for convenience and cost savings. The quarterly sewer service charge for residential customers is determined by your water consumption during the prior winter quarter which represents water used indoors and excludes water used for irrigation, washing cars, etc. that does not enter the sewer system. Funds collected for sewer charges are then transferred to the Sanitary Sewer Fund, which is used to support the operations and maintenance of the collection system and the treatment plants.

The Fairfax County sewer collection system consists of approximately 3,300 miles of pipe and 63 pumping stations. Your home or business is connected by a service line, called a sewer lateral, to the sanitary sewer system. The Wastewater Collection Division of the Fairfax County Department of Public Works and Environmental Services operates and maintains the collection system. Property owners are responsible for maintaining the sewer lateral.

• Do not pour cooking oils and grease down your household drains. Cooking oils and grease should be disposed of in the trash, as they may cause problems in your service line and possibly the county sewer.
• Do not vandalize or tamper with sanitary sewer manholes. If you see anyone lifting manhole covers and putting objects such as sticks, logs, bricks, glass bottles, etc., down the manholes, please report it immediately. This tampering causes sewer blockages which result in sewer backups or overflows into homes and backyards. Report acts of vandalism or tampering with manholes to 703-323-1211, TTY 711. Vandalism to the sewer collection system creates significant environmental problems and increased costs for county sewer rate payers. Your assistance will help in keeping your neighborhood from experiencing sewer backups and spills.
• Do not flush wipes, even those labeled as flushable, or other items such as feminine hygiene products, cotton balls, cotton swabs, and dental floss. These should be disposed of in the trash as they may cause problems in your service line or possibly the county sewer.

Some regional parks have disposal locations. The Noman M. Cole, Jr. Water Recycling Facility accepts RV waste from county residents, but requires prior notification so an escort can be provided.

See list of disposal locations that are available online.

If swimming pool water is released improperly, it may have a negative effect on the environment. Guidelines for swimming pool discharges can be found on the Proper Discharge of Swimming Pool Water webpage. For more information, email the Stormwater Planning Division or call 703-324-5500, TTY 711. Commercial swimming pool operators should call the Health Department at 703-246-2300, TTY 711.

When public sewer is not available, a septic system may be installed with the approval from Fairfax County Division of Environmental Health. For more information on septic systems, please visit the Division of Environmental Health website or call them at 703-246-2201, TTY 711.

Homeowners whose septic systems are failing, and deemed non-repairable by the Division of Environmental Health, will be required to connect to sewer if the property is within 300 feet of available public sanitary sewer.

For failing septic systems where sanitary sewer is not available, property owners should contact the Division of Environmental Health for available alternatives.

All outhouses in use today in Fairfax County have been grandfathered. All new construction will be required to have a sewage disposal system that is approved under the current codes.

Please visit Land Records Division of the Fairfax County Courts or call 703-691-7320.

There are over 3,300 miles of sewer lines that convey wastewater around Fairfax County. In some situations, it is necessary to clear trees, brush, and even tree roots from areas to ensure access to the sewer line for maintenance activities like inspection and cleaning. This clearing also enables the county to quickly reach these locations with its equipment during emergencies and minimizes the potential impact of a Sanitary Sewer Overflow (SSO). Tree roots can damage sewer lines and cause blockages and broken pipes, which can lead to SSOs.

The county will do a site restoration of areas that have been cleared for sewer line construction or maintenance. The types of vegetation replanted in each easement is specific to the project and the site.

We remove trees in a controlled, safe environment to save valuable time during emergency responses, such as a Sanitary Sewer Overflow. Our goal is to provide a safe environment for our staff, homeowners and the public, free from the hazardous contaminants found in wastewater. Cutting trees in a preventive measure allows for immediate and safe access to sewer lines and eliminates the need to clear the easement at the time of response, when time may be of the essence.

Removing trees that are too close to sewer lines also prevents sewer clogs and sanitary sewer overflows, as tree roots have been reported to “cause >50% of all sewer blockages.” Tree Root Intrusion in Sewer Systems: Review of Extent and Costs (usda.gov)

Our objective is to ensure 100% accessibility for maintenance work within all easements. Clearing is prioritized based on maintenance records and construction initiatives, and whether Sanitary Sewer Overflows have been an issue.

The county makes a site-specific determination on the risk that trees present to a sewer line and maintenance access. In some cases, the county removes all trees within the easement. In other cases, the county does not remove trees that show no risk to the sewer line. In some major maintenance and construction projects, the county must remove all of the trees within an easement to achieve the project objectives.

The reimbursement program provides payment to developers who have upsized Fairfax County wastewater infrastructure. Developers are responsible for the planning, design, and construction of the sanitary sewer asset and must follow the typical County development process. At project completion, the County will reimburse the developer the proportional cost share of the project. The developer is responsible for the cost share associated with the flows from their development. The County is responsible for the cost share associated with the existing and future flows.

When areas redevelop, the existing sewer may not have the capacity to handle increased wastewater flow. Developers who are adding flow to sewers that are at capacity must upsize sewers to ensure the system can accommodate existing and future demand. Undersized sewers may result in sanitary sewer overflows which is a public health hazard.

Fairfax County staff review all development plans to determine the impact of the proposed development to the sanitary sewer system. If the additional flow from a development will exceed the capacity of a sanitary pipe, the development is responsible for upsizing that pipe. The new pipe must be sized to accommodate existing flow, the development flow, and all potential future flow. The developer is responsible for installing the pipe, and the pipe must be in operation prior to the development connecting to the County system. After project completion, the County will assume ownership and will be responsible for operation and maintenance of the sanitary sewer asset.

The pipe upsized by developers is designed to accommodate flows from both existing and future users. Therefore, the County’s portion of the reimbursement program is funded through existing and new users. The program is primarily funded by availability fees (tap fees) collected from new users, where “growth pays for growth.” New users pay for the right to add their flow to the sanitary sewer system. Existing users benefit because the new pipe guarantees a functional, brand-new pipe, and a small amount of the user fees are applied to help fund the program.