
Sanitary Infrastructure

What Can You Do to Help Protect the Sewer System?
We can all make a difference in helping to protect the sewer system. Sanitary sewer systems and wastewater treatment facilities are designed to collect and treat dirty water that has been used for toilet flushing, bathing and showering, washing clothes and dishes and other normal residential, business and institutional purposes. However, when certain items enter the sanitary sewer system, sewers can become clogged leading to sanitary sewer back-ups and sewer overflows into the environment. Below are some simple actions you can take to help protect the sewer system:
- “Can the Grease”. DO NOT dispose of grease and oils into any sink or drain. Instead pour grease into a can, cool the can in the freezer, and then discard in the trash.
- Wipe grease out of pots and pans with a paper towel prior to washing. Place paper towels in the trash.
- Minimize use of garbage disposals as many foods are cooked or contain additional oils. Use strainers on sinks to catch food scraps and dispose of in the trash.
- DO NOT flush non-degradable materials down the toilet. These include items such as so-called “flushable” wipes, paper towels, condoms, and personal hygiene items (tissues, feminine care products, Q-tips, etc). Instead place these items in the trash.
- DO NOT flush medications down the toilet. Flushing medications into the sewer system pose a hazard to water quality. Instead, mix them with substances like kitty litter or used coffee grounds, place mixture in a seal-able bag, and place in a secured trash can. Alternatively, you can return these medications during Drug Take-Back Days or at permanent disposal locations. To locate a permanent disposal location, please visit the U.S. Department of Justice's Diversion Control Division website.
- Report any sanitary sewer issues to the City by calling 311 or 703.746.4311.
RiverRenew Program for the Combined Sewer System

The City’s combined sewer system dates back to the 1800s and comprises approximately 540 acres located in the Old Town area. During most wet weather events, combined sewage (a mixture of wastewater and stormwater runoff) discharges through one of four combined sewer outfalls into receiving waterways.
In April 2017, the Virginia General Assembly passed a new law requiring the remediation of these outfalls by July 1, 2025. The City, working with Alexandria Renew Enterprises (AlexRenew), submitted a Long Term Control Plan to the Virginia Department of Environmental Quality (VDEQ) in 2018.
This plan calls for the construction of an underground tunnel system to bring combined sewage to the AlexRenew wastewater treatment facility, thus significantly reducing both the number and volume of combined sewer discharges into City waterways. As of July 1, 2018, VDEQ has approved the plan and the City has transferred ownership of the combined sewer outfalls to AlexRenew. AlexRenew is implementing the plan as part of its RiverRenew Program.
To find out more information about the RiverRenew program, including details about its pre-construction community listening sessions, please click here.
Programs and Projects
City Council - AlexRenew Board Project Review Workgroup Subcommittee
To facilitate partnership between the City and AlexRenew, and to provide a liaison for input and feedback, this workgroup will review and guide the plans, design, implementation, costs and financing of the combined sewer construction project with the intent of minimizing community impacts and maximizing community benefits. The next City Council/AlexRenew Board CSO Workgroup meeting was held on Thursday, April 27 from 5:00 PM to 7:00 PM. The meeting was held at Alexandria Renew Enterprises, 1800 Limerick Street, Room 600. For information about upcoming meetings click here and for more information about the work group, click here.
Combined Sewer System Community Engagement
Building off the foundation from previous groups, the new RiverRenew Stakeholder Advisory Group (SAG) will monitor construction progress on the Tunnel System Project, the largest infrastructure project in Alexandria's history. The next SAG meeting will be held on Thursday, May 19 from 7:00 PM to 9:00 PM. The meeting will be held at virtually. For information about upcoming meetings click here and for more information about the Stakeholder Advisory Group, click here.
Fats, Oils, and Grease (FOG) Program
The City has developed a Fats, Oils and Grease (FOG) program to reduce the amount of FOG introduced into the sanitary sewer system, which can lead to sewer back-ups and sanitary sewer overflows into the environment.
City Assistance Program For Sewer Backflow Prevention
The City of Alexandria offers assistance to homes that may have experienced a basement back up or flooding after a heavy rainfall and are interested in having a licensed plumber install a backflow preventer.
Sanitary Sewer Asset Renewal Program
The City is implementing a Sanitary Sewer Asset Renewal Program, which will provide for the inspection and rehabilitation of all City sanitary sewers, manholes, and City-owned portions of lateral sewers. A total of $33 million has been programmed over the next 10 years as part of the City's Sanitary Sewer Capital Improvement Program. The first phase of inspections included sanitary sewers generally bounded by Commonwealth Avenue, Four Mile Run, Route 1, and the Metro rail lines. Inspections for the first phase began in early 2021 and concluded in December of 2021. Second phase inspections, west of Commonwealth Avenue, will begin in May 2022. The completion for the second phase of inspections is estimated to be in early 2023. Sewers and manholes that are found to either be structurally deficient will be rehabilitated, with a rehabilitation program scheduled at the end of 2022.
Old Town Sewer Assessment and Rehabilitation Program
This project provides for the condition assessment of all sewers in the Old Town area (including the combined sewer area) of the City and remediation of structurally deficient sewers and sewer structures. This project will be completed in several phases. The first phase will begin in March 2019 and will consist of physical inspections of all manholes and inlets in the Old Town area. This phase of the project is anticipated to last approximately 12-18 months. The second phase begins in March 2020 and will include inspection of all sewers in the northern half of the Old Town area.
Sanitary Sewer Geographical Information System (GIS)
There are over 240 miles of sanitary and combined sewers located within the City. Information about these sewers are available to the public on the City’s GIS Sewer Viewer.
The Sewer Viewer displays the sewer network, and includes information such as pipe diameters, flow directions and manholes.
About the Division
The Sanitary Infrastructure Division is responsible for:
- Planning level engineering encompassing over 240 miles of sanitary and combined sewer within the City
- Development and implementation of the City’s 10-year Sanitary Sewer Capital Improvement Program
- Coordination with the City’s Department of Project Implementation related to design and construction of sanitary sewer capital projects
- Coordination with Alexandria Renew Enterprises on the RiverRenew Program for the combined sewer system
- Review of development and redevelopment plans in order to ensure adequate sewer capacity to accommodate growth and identify when upgrades to sewer infrastructure are required to serve new development
- Ensuring that development projects located within the CSS comply with the City’s CSS Management Policy for development/redevelopment