What Are Water Mains?
Water mains are pipes that carry drinking water to homes and businesses. Arlington’s water mains range from 48 inches to one inch in diameter, but most are six inches or eight inches.
View the County's interactive water main break map of ongoing repairs and work completed within the last 30 days.
Did You Know? There are approximately 500 miles of water mains and five pumping stations in Arlington’s system.
Water Main Breaks
As more than 60 percent of Arlington’s water mains are 50 years or older, breaks in the pipes are both unavoidable and unpredictable. Each break brings its own set of challenges. Small breaks are easier to fix, but can be harder to find. Large breaks can wreak havoc on traffic and sometimes cause damaging floods and water shortages.
What causes breaks?
In addition to age, other factors in water main breaks include:
- Installation configuration
- Previous repairs
- Variations in water pressure
- Seasonal temperature changes
How do we know when a pipe breaks?
We regularly monitor water pressure at various points in the system as a drop in pressure can signal a problem. But often, the Water, Sewer, Streets Bureau staff learn of a break when a resident calls the 24-hour emergency hotline, 703-228-6555, to report water flowing from the street (or elsewhere outdoors) and possibly a loss of water pressure in nearby homes. Then a crew is sent to investigate.
If crews find no obvious source for the outdoor water flow, they run tests to help determine whether it’s drinking water or groundwater. If it’s drinking water but no break is visible, the crew uses leak-detection equipment to “listen” for and locate the break.
How do you fix a leak?
Once a crew finds a leak, it closes the valves on the pipe to stop the flow of water to the broken section. This might cause a temporary service disruption to some properties. After isolating the broken section, the crew repairs or replaces it depending on the type and severity of the break.
In most cases, repairs are made within several hours to a day after the first report. However, repairs on major water transmission mains may require complex repairs that take longer to complete.
Weather and Water Mains
Cold weather and freezing temperatures create stress on our water and sewer infrastructure, increasing the chance of leaks. With approximately 500 miles of water mains and 465 miles of sanitary sewer pipes to monitor, residents play a crucial role in reporting breaks.
If you suspect you've seen the flow of a water main break or are experiencing low water pressure, call the 24-hour emergency hotline at 703-228-6555. Once WSS has been notified, an experienced employee or crew is dispatched to investigate and assess the problem. The County's Report a Problem online tool may also be used but there could be a delayed response to a service request depending on day and time.
Main breaks that leave customers without water service are given highest priority for repair. When a break is identified, the water is turned off to the immediate area and repairs begin. Though crews work quickly, work can take eight hours or more.
The emergency has been reported. Now what?
When we receive a call about a leak or break, several steps are taken.
- Getting the information. An operator will ask the caller questions to collect information about the location and severity of the situation so WSS staff can respond effectively.
- Evaluation. When a crew arrives on-site, they’ll determine if it’s necessary to shut down the water main. In many cases, the main break itself may interrupt water service or reduce water pressure for customers.
- We’ll inform affected residents as soon as possible of a water main break. Yet when there are unsafe conditions or property damage, we may opt for an emergency shutdown, giving us little opportunity to provide advance notice. Sometimes the presence of a crew in the area and low or changing water pressure are the only initial notices we can provide of a water main break.
- If critical businesses or organizations — such as restaurants, office buildings, schools and hospitals — are affected by a main break, WSS staff will work to accommodate them with temporary services as feasible.
The Water, Sewer, Streets Bureau works to repair a water main break on South Courthouse Road.
Repairing the Main
When a water main break is confirmed, a crew will set up a work zone and detour traffic. The crew will also turn off the main (immediately if needed) and contact Miss Utility to mark the various utilities near the break as required by law. After the utilities have been marked, the crew will excavate and secure a trench and begin repairs. Crews work continuously to repair breaks and restore water service; however, unforeseen challenges can arise causing the process to take longer, including:
- Older malfunctioning valves
- Delays marking utilities or missmarked utilities
- Working around other utilities (gas, telephone, power or fiber optics)
- Weather conditions
- Equipment problems
- Safety of repair crews
When a repair response is under way, water main breaks are automatically posted on the DES Twitter account, giving the address, the number of likely customers without service and an estimated time for repair completion. The response is also posted on the County's online water main break map, which shows current operations and those from the last 30 days. The County also posts water main break repair notices on Nextdoor if there are a number of customers without service in a Nextdoor-recognized neighborhood. In the case of a serious, widespread situation, the local media may also be notified. Residents may be asked to conserve water during an emergency so it's always good to have a few gallons of drinking water stored away. A boil water notice resulting from a water main break is rare but possible if pressure in the County pipe network falls below a safe level, potentially allowing for contamination to enter the system.
In most cases, when the water pressure returns, you’ll need to run the cold water tap for a few minutes to clear the pipes. Use of hot water may draw discolored water into your hot water heater, prolonging a potential disruption. If after five minutes you still notice discoloration or a strange odor, call the 24-hour emergency hotline at 703-228-6555. A crew can be dispatched to flush the system through fire hydrants and/or at your meter location.