What Does It Mean When Water Keeps Backing Up in My Tub?

Water backing up into your tub on a regular basis that drains very slowly—if at all—means that you have a clog somewhere in your drain pipes. The problem is that it's not always immediately apparent where this clog is, and so it can be hard to figure out what to do next. Don't panic just yet; while you may need to look into getting your septic tank emptied to fix the problem, this is not the only possible source of water backing up. Before you call a plumber, get ready to do a little searching.

Find the Clog

If water isn't draining from your tub, there are two possibilities: the tank is full, or there is a clog somewhere. The clog doesn't necessarily have to be in your main line; what appears to be a septic clog could simply be a drain clog. There are a few ways you can find out.

In the same bathroom as your tub, turn on a faucet or flush a toilet. If the main line is clogged, the draining water from any drain higher than your tub will bubble back up into your tub. If nothing changes in the tub, the clog is somewhere before where its drain pipes meet those of the sink and toilet.

You can also go outside and look at your main line. The main line exits your house and drains into the tank, but between your house and the tank is a vent pipe that comes up to the surface, typically covered by a plastic grate. Take off this grate and use a flashlight to look down. If there is a lot of sitting water, the clog is nearer to the tank. If not, the clog is nearer to your house. If you have a plumber's snake, use this to try to break up the clog. If you don't, try running a garden hose down the vent pipe on full blast to see if the water pressure can break it up.

Look at Your Tank's Sludge Level

If there is still no discernible clog, there is a chance your tank could be full. If it's been a few years since you last had it emptied, this could be the case. If you know the location of your tank in your yard, you can take a look yourself.

Every tank's access hole is on top of the tank, generally a few inches below the ground. This may be marked somehow, or you may know where it is from the last time it was emptied. Dig up this access hole and open the cap. In every septic tank, the sludge sits at the bottom while water and oils float on top; if you see only sludge and it's very near the surface, your tank is nearly full and will need to be pumped.

If not, your tank may be at acceptable levels, but for some reason the water on top is not draining out into the leach field like it should. When the water on top doesn't drain into the leach field, it eventually has nowhere to go but back up the tank's inlet and into your house. In this case, your tank is fine but will likely still need to be pumped to lower the water levels.

What You Can Do

If you can't fix the problem on your own, apart from calling a septic company or plumber, there are some things you can do to help. First, make sure that the access cap to the septic tank is dug up and accessible to the plumber. If nothing else, this can save you a few bucks, as many plumbers and septic companies charge extra to dig it up. Second, use water sparingly. If you need to use any, use a bowl to catch any water instead of letting it drain normally.

For more information about septic-tank pumping, talk to a company like Rob's Septic Tanks Inc.