Keeping Your Water Supply Safe: Backflow vs. Backwater

Now that summer finally seems to be here, I thought I would take a minute to address a misunderstanding that came up during the spring floods. I have heard several customers say, “Should I have a backflow preventer installed to prevent this flooding from happening again?” When it comes to protecting our water supply and our houses, there are two different, but complimentary technologies that work together to keep us healthy.

The first is backflow prevention. This is a way of protecting your potable water supply using a device called a backflow preventer. They are usually required by your local government if you have a home spa, a boiler system, a chemical based lawn sprinkler, or some other cross connection potential.  This hunk of brass or bronze is connected to your incoming water supply and prevents any chemicals or other toxins from being sucked into your house/well/municipal supply when the fire department hooks into the system and activates their giant pumpers. A backflow preventer is testable and needs to be re-certified every year by a licensed backflow prevention technician.

The other device is called a backwater valve. It is installed in your homes sewer line and stops any raw sewage from backing up into your basement and causing a big mess. Sometimes in high water times or in the case of a blockage, the city sewers can fill up to capacity and the only place for the ugliness to go is into your rec room. A backwater valve clamps shut and prevents this unpleasantness. They are suggested for use in low lying areas where the potential for flooding is high. Checking with your local water authority is a good way to find out if you need one.

Unfortunately, this past spring was an extreme example of when neither device would be of much use in your house. When the water is so high that it crests the river banks and moves into populated areas, the best thing to do is to sandbag around your property and have a good pump on hand to get rid of any water that gets through the barrier.