Today I am going to identify something you probably drive by at least a dozen times on your way to and from work, and that is a backflow preventer. Similar to the one pictured, you will find these little gems tucked away on the corner of every commercial property as well as larger homes and condo/apartment complexes. So what is it and what does it do?
Backflow preventers do exactly what they sound like they do, prevent water from going into the potable water supply once it has left the municipal system. How can this happen you ask, as the water is under pressure when it is delivered to our homes and businesses? There are a few different scenarios in which backflow can occur. The most common is something has caused the water pressure to drop drastically. Things such as a water main break or several fire hydrants being opened in the event of an emergency can cause that water pressure to drop like a rock.
Here’s the scenario I would like you to ponder… Someone has a hose hooked up to a faucet on the side of the house and the other end is in a big bucket of soapy car wash water. The water pressure drops, and all that soapy water gets sucked back into the drinking water supply and then is re-delivered to the home once the water pressure has been re-established. I am describing the smallest of scales here and a little soapy water from a five gallon bucket wouldn’t do much in terms of fouling up our water supply. Now, let’s take it up a couple of notches. What if that is a four-inch hose in a big vat of some form of toxic chemical and the same thing happens? That could be disastrous for hundreds or perhaps thousands of people.
There are several different types of backflow preventers out there; however, the most common is a double check valve that only allows the water to flow through in one direction. Building codes require that all backflow devices are tested and certified on an annual basis by a backflow specialist. Most cities require that you send a backflow report to them on that same annual basis, and if you do not in some cases, the city will turn off the water supply until the required testing and certification is completed.
Backflow certification costs vary depending on the size of the device, and they can range from a one-inch diameter all the way up to twelve-inches on some bigger fire suppression systems. As always if you have a backflow device that needs a little attention we are a simple click or call away.
Until next week… I know most of my puns are cheesy, however they make me feel grate.
House Whisperer out!