Flooding & Drainage

Flooding is the number 1 natural disaster is our country. Learn more about what the City is doing to help improve flooding and drainage issues and how you can be flood smart and what you can do to help protect your property.

Page updated on Aug 6, 2020 at 7:36 AM

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City of Alexandria Advises Residents on Cleanup Following Flash Flooding

Following the severe storms and flash flooding of July 23, 2020, the City of Alexandria reminds residents to exercise caution and be alert for impassable roads, power outages, home sewer backups, and other flood-related issues. Based on preliminary indicators, last night’s severe storm dropped 2-3 inches of rain in 30 minutes, creating a brief, extremely high-intensity event that caused significant flash flooding in many areas of the city, including some that are not normally impacted. 



City crews are currently inspecting and cleaning culverts and clearing curb inlets of debris that may have clogged them during the flooding. Residents removing debris from their property or homes should place it curbside for pickup on their next refuse collection day. 


To report a power outage, call Dominion Energy at 866.366.4357. If you encounter an intersection with an inoperable traffic light, please use caution and treat it as a four-way stop.

Never attempt to turn off power at the electric panel if standing water is present. Call your building manager or electric utility to shut off power outside at the meter. Never step into a flooded room if water may be in contact with electrical outlets, appliances or cords. Never touch electric wires, switches or fuses when you are wet or standing in water.

Missing Utility Hole Covers 

Please do not attempt to move utility hole covers. Report problems via Alex311 either online or by dialing 311 (703.746.4311).

Sewer Backups 

Cleanup of sewage backups in homes and businesses is the responsibility of the property owner. Property owners are advised to take the following actions after a sewer backup:
1. Take photos of the damage to basement rooms and furnishings.
2. Report the damage to your insurance company.
3. Put damaged carpet, furniture, and other household items at the curb at your next trash collection day for free pickup by City crews if you normally receive City trash collection.
4. Contact a commercial firm that provides cleanup following water damage, if necessary.
5. After the rain stops, if sewage has come through a floor or plumbing drain, open the drain to allow as much water to drain out as possible; use buckets, sump pump or other means to remove as much of the contaminated water as possible.
6. Individuals wishing to file a claim with the City should call the Office of Risk Management at 703.838.4549. All claims will be investigated.
7. For health-related questions, contact the Alexandria Health Department, Environmental Health Division, 703.838.4400, ext. 266.

Residents who experience regular backups and reside in certain flood-prone areas of Alexandria may benefit from the City's sewer Backflow Preventer (BFP) Assistance Program for homeowners.

Stay Informed

Flash floods develop quickly during periods of heavy rainfall, sometimes in just a few minutes. Staying informed and being prepared for flooding is one of the best ways to protect yourself and your property. Sign up for alerts from the City of Alexandria and the National Weather Service for severe weather updates. 

City Operations and Maintenance

The City has about 185 miles of storm sewer pipe, about 13,500 storm structures, and about 26 miles of streams. City crews and contractors perform proactive maintenance on storm sewer infrastructure and in response to complaints to remove any blockages and to ensure that the storm sewer infrastructure is functioning as designed. Regular street sweeping of roadways is performed to aide in the removal of nutrients and pollutants from our local waterways while removing road debris to prevent it from entering the storm sewer system.

How Do You Protect Your Property?

Determine Your Flood Risk

The Federal Emergency Management Agency (FEMA) creates Flood Insurance Rate Maps (FIRMs) that show floodplain boundaries. As of 2011, approximately 20% of the City is mapped by FEMA in a floodplain. However, extremely high-intensity storms may cause flash flooding in areas that are not normally impacted, to include properties that may not be in a designated FEMA floodplain. Please visit the Flood Map page for more information on the FEMA flood maps. The City of Alexandria offers a complementary notification service called "eNews" that sends a text or email alert in the event of a flood. To sign up, visit www.alexandriava.gov/eNews.

Purchase Flood Insurance

Most homeowner’s insurance does not cover property damage from flooding but homeowners may purchase flood insurance through the National Flood Insurance Program (NFIP), even if your property is outside of a FEMA-designated floodplain. Alexandria participates in the NFIP’s Community Rating System (CRS) program, a voluntary incentive program that recognizes and encourages community floodplain management activities that exceed the minimum program requirements, and scores those activities to determine “classes” for those communities that participate. Recognized as a "Class 6" community, Alexandria homeowners are eligible to receive up to a 20% discount on flood insurance premiums. 

Make a Flood Plan

Know evacuation routes and keep important papers in a safe, waterproof place.  Please visit the Flooding Information page to learn more about to protect your property during flood events.

Be Flood Smart

Flooding is the nation’s #1 natural disaster and it can happen anytime and anywhere. Floods occur in all 50 states and you can be a victim of flooding, even if you live miles away from water. Learn more on what causes flooding and how to protect your property by visiting FEMA's Flood Smart web site.

Help Prevent Local Flooding

You can help prevent local flooding by keeping trash and other debris, like tree branches, away from storm drains and inlets. Please visit the Waterfront Plan Implementation page for more information on flood mitigation projects along the waterfront. Utilize the Alex311 system to report storm sewer blockages or issues on public property. 

City Flooding and Drainage Projects

The increasing frequency of more intense storm events has created more frequent flooding and drainage issues. The City identifies flooding and drainage projects through resident complaints, analyses, and field observations. These include small to medium ‘Spot Improvement’ capital improvement program (CIP) projects to mitigate drainage issues. After identification and initial investigations, these projects often require work to identify CIP resources, perform onsite survey, complete design, secure right of entry (if applicable), and procure a construction contractor to perform the work. The City completed the initial Storm Sewer Capacity Analysis that identified problem areas and prioritized potential locations for large, multi-year CIP projects to address capacity issues.

spot improvement projects

Since 2019, the City has completed five storm sewer spot improvements to make quantifiable repairs for many residents impacted by flooding. The City has $4.7 million in the current CIP for similar projects and uses a proactive, methodical approach to prioritizing these types of projects. Staff will continue to update its list of projects as they are completed, statues change, and as others are identified:

Project Description Status Completed
W. Alexandria Alley Improve alley drainage for nearby residents Completed FY 2019
Founders Park Repair infrastructure to improve drainage for park, adjacent property (parking garage) Completed FY 2019
901 N. Ashton Street Emergency repair of pipe, mitigate erosion, and restoration Completed FY 2019
Saylor Place Replace rusted ditch pipe with polyethylene plastic pipe Completed FY 2020
Angel Park Install infrastructure for street and park drainage Completed FY 2020
Hancock Ave at Alexandria Alley Install storm pipe at culvert Design nearly complete FY2021
708 W. Braddock New storm inlet Purchase Order FY2021
Lloyd’s Lane Drainage improvement, street onto private property Design complete FY2021
4320 Loyola Avenue Replace existing open channel with closed pipe to mitigate drainage issues Survey and Design near completion FY2021/2
Mt. Vernon Ave Cul-de-sac Replace inlets Preliminary analysis FY2021
Mt. Vernon Alley Improve alley drainage Preliminary analysis FY2021/2
Carlisle Drive Alley drainage improvements Preliminary analysis N/A
Key Drive Unnamed Tributary Channel Wall Channel wall is degrading in places; utilities exposed Preliminary analysis FY2021/2
Oakland Terrace Timber Branch Wall Degrading and eroding around it Preliminary, Easements FY2021
Walleston Ct. Stream Bank Stream bank erosion Maintenance N/A
636 W. Timber Branch Pkwy Retrofit catch basin to fix drainage issues Preliminary Design FY2021/2
Douglas Cemetery Undersized/condition Field analysis Planned


Capacity Projects 

In February 2016, the City finalized a summary report of the City of Alexandria Storm Sewer Capacity Analysis (CASSCA) project, the purpose of which was to analyze the storm sewer system, identify problem flooding areas, and develop and prioritize solutions. The City conducted the study in response to flooding in June of 2006.  The City is working on the design and construction of large capital projects based on this analysis, which identified problem flooding areas and prioritized potential projects to alleviate storm sewer capacity issues.  

2020 Hooff’s Run Inspection and Cleaning Project 

In June of 2020, the city hired a contractor, Red Zone Robotics, to inspect and survey approximately 7,000 feet of the Hooff’s Run Culvert which conveys stormwater from a significant portion of Northridge, Del Ray, and Rosemont. The survey identified overall debris levels in the range of 5% with isolated sections of pipe having debris accumulation of approximately 15-20%. An overview of the report can be found here. T&ES staff is working with contractors to obtain cost estimates and to develop a plan to have the debris removed from the culvert.