Questions and Answers

Why Now? - If the Occoquan Dam has been there for 50 years, why are you just now installing a siren system?

Great question! We have installed the sirens for two reasons. First, because of changing regulatory requirements, our regulatory agency - the Federal Energy Regulatory Commission - has suggested that we install a sound-related system to inform people downstream of the dam in the extremely unlikely event of a dam structural failure. The second reason is that when we worked with the communities closest to the dam, namely the Town of Occoquan, it was the Town's feeling that a siren system would be the most effective and desired form of communication to alert people to the extremely unlikely event of a dam failure.

How strong is the dam?

Very strong. The structural integrity of the Occoquan Dam is very sound. In fact, through rigorous maintenance and improvements, it is even stronger today than when it was constructed. The dam is approximately 72 feet tall and 70 feet wide at its widest point. It is anchored to the bedrock below the bottom of the dam and to the sides of the reservoir. It contains more than 100,000 cubic yards of reinforced concrete. That is equivalent to:

What does the siren sound like?

You can hear what the siren sounds like by clicking here.

What if I have other questions that I can not find the answer to here?

You can direct any further questions you may have to Fairfax Water's Public Affairs Department by email. Please click here to submit a question.