Do you have a dishwasher that isn't draining properly and instead fills up with water? If so, see some reasons why you might be having this plumbing problem.

The Drain Hose Is Damaged 

Your dishwasher will have a hose that exits the dishwasher and connects to your kitchen sink drain or garbage disposal. Chances are that you are having a problem with this hose, so you'll want to check it out to see what is wrong with it. The problem is that this hose is typically a flexible hose that is fairly small, rather than a PVC pipe that is big and sturdy. Make sure that this hose is still in good condition and not damaged. For example, a flexible hose may become crimped, causing water to struggle through a small opening. 

The Drain Hose Is Clogged

It is also possible that you have something in the drain hose that is causing a clog, where that clog has now narrowed the inside diameter of the hose and prevents water from passing through. You may have to disconnect the pipe and get out whatever is inside the pipe, or simply replace the entire hose with a new one if you can't reach inside to get the clog out.

The Drain Hose Is Not Looped

Since the drain hose goes from your dishwasher to the sink drain, it needs a way to prevent water from flowing back into the dishwasher from the sink. This is sometimes done by having the pipe form a loop so that the water has to flow up and back down to prevent it from accidentally going into the dishwasher. If you do not have that loop in the pipe, then it's possible that the water from a sink is easily flowing back into the dishwasher, which is making it appear as if it is backed up. Consider adding a loop to the pipe to prevent this from happening. 

The Check Valve Is Broken

Some people do not loop the tube and use a check valve instead. This valve allows the water to flow in one direction so water doesn't flow back into the dishwasher. Unfortunately, this check valve can become damaged over time and be stuck in an open position. The solution may be to replace this check valve so that water only flows out of the dishwasher.

Reach out to a plumber in your area, like Merrell Plumbing, for help making repairs to this part of your kitchen plumbing.