The miracle of indoor plumbing allows us to effortlessly wash and flush waste away from our homes -- but that pipeline isn’t always a one-way street. When various problems arise, noxious sewer odors can come marching right back up the pipes and into your home. In addition to being unpleasant, those odors can bring health risks along with them, so it’s important to address the situation right away.
Fill the Trap
Fortunately, one of the most common causes of sewer odors in drains is also the easiest to fix. Smells can waft into a room if a drain pipe’s water trap has gone dry, and solving the problem is as easy as running a little water. If you look underneath any sink in your home, you should notice a u-shaped bend in the pipe. That’s the water trap, and if you ever accidentally wash your wedding ring down the drain, that’s hopefully where you’ll find it. But the real reason it exists is to hold water at all times, creating a water barrier between your home and all the icky things lurking further down the pipe. If you don’t run any water down a particular drain for a very long time, that water can evaporate to the point where sewer smells can make their way through. All you need to do is run the water for several seconds to refill the trap, then wait a little while to see if the odor goes away. For floor drains, you can do this by slowly pouring in a bucket of water.
Clean the Pipes
If the culprit isn’t a dry water trap, there’s a chance that a stinky biofilm has built up inside the offending drain pipe. This is more common in kitchen sinks or drains where food or other biological material is regularly washed down the drain.
The only way to solve this problem is to scrub the slime away, which can be easy or difficult depending on the pipe. If you’d like to take a crack at it yourself, you can remove the drain cover and scour the inside of the pipe with a long, flexible pipe brush. Spraying a 50/50 mixture of bleach and water down the drain so that it coats the inner pipe walls will also help deodorize.
If that doesn’t cut it, it’s time to consult a professional plumber for a more thorough drain cleaning.
Call in the Pros
The real trouble begins when you notice the same sewer smell coming from multiple drains. If the home has been vacant for a while, try filling the water traps. But if the water traps are full and the odor is coming from everywhere, you probably have a bigger problem deeper in the sewer system. This could be a problem with your plumbing equipment or with that of your local sewer authority, so you should consider calling the utility provider to investigate the problem. If the problem turns out to be on your end, you’ll need a plumber to track down the source. This may be possible with a camera inspection, but the worst-case scenario could involve digging in the yard or even the basement. Nobody likes to start a major repair like that, but when your home is starting to smell like a sewer, there’s no time to wait. Call your local plumbing pros and get help on the double!