Occoquan Dam Siren Test 2020

This Wednesday, November 18,2020 at 10 am Fairfax Water will test the Occoquan Dam siren system. The sirens are installed along the banks of the Occoquan River between the Town of Occoquan and Belmont Bay. People living and commuting in the area will hear a loud siren at 10 am on Wednesday November 18th. The test has taken place annually since 2012, but to many this may be the first time they are hearing it. Don't panic, it's just a test. 

The Occoquan Dam, also known as “the High Dam” was built in the 1950s to create the Occoquan Reservoir that now holds approximately 8 billion gallons of water. The dam is an essential element of our 24/7 water supply. The dam is owned and maintained by Fairfax Water who performs regular maintenance inspects the dam regularly. Fairfax Water states that “Rigorous maintenance and improvements to the dam have made it even stronger today than when it was constructed. It is extremely unlikely that the dam would become structurally compromised but we still want everyone to be prepared and safe.”

In 2012 Fairfax Water, Town of Occoquan, Fairfax County, and Prince William County installed the siren warning system as a precaution in the unlikely event of a structural failure. The siren is to alert folks downstream of the dam of the failure so they can evacuated to higher ground. The sirens are used because the Town of Occoquan felt that a siren system would be the most effective way to alert people in the unlikely event of a dam failure. You can also sign up to receive news and updates from either Fairfax and or Prince William Counties on your devices. You may choose to receive notifications via phone calls, text messaging, e-mail and more.

To sign up for Fairfax Alerts, visit: www.fairfaxcounty.gov/alerts.

To sign up for Prince William County Alerts, visit: www.pwcgov.org/pwcan.

In the unlikely event of a structural failure at the dam, the loud siren will sound, and residents and visitors in the impact zone indicated in red should immediately evacuated to higher elevations to avoid the torrent of 8 billion gallons of water. Those on the water should get to land.