Water leaking from the bottom of your dishwasher is never a good sign. Several issues can lead to this problem, so troubleshooting is needed.
Often, dishwasher leaks are very obvious because a large amount of water will begin to drain out from below your dishwasher and onto the floor. In other instances, though, leaks may be more minor so water accumulates slowly and there is no large puddle.
In the second instance, you may first notice that there is a leak because the flooring around the dishwasher begins to warp. This is especially likely if you have linoleum or vinyl kitchen flooring. You may also notice water stains or pick up mildew odors around the dishwasher. Leaks can also affect the cabinet next to the dishwasher, where water damage may happen to the wood cabinetry.
Water leaking from the bottom of the dishwasher is usually a door or a drain problem. If it comes from the bottom of the door, then the gasket is likely to blame. It may be worn out, be warped, or have something stuck in it that prevents it from sealing correctly. A failing door latch could also be the culprit, as could a clogged drain inside the dishwasher that is leading to overflow.
Water that flows out from beneath the dishwasher or in the under-sink cabinet next to it indicates damage to the drainpipe or hoses. If the leak only happens when running the kitchen sink, then the location of the dishwasher drain pipe is a problem. If it happens when the dishwasher is draining, then there is likely a leak in the drainpipe itself.
Door problems are easily repaired. Gaskets can be cleaned or replaced, as can door latches. If the drain inside the dishwasher is clogged, it will only need a thorough cleaning to remove all residue from the drain. The drain filter will also require regular cleaning so the clog doesn't reform.
Drainpipe issues may require more involved repairs. When leaks only occur when the sink is being used concurrently with the dishwasher, moving the pipe is the only possible way to fix it. The dishwasher drain line needs to be placed so it is higher than the sink drain line. This prevents sink water from backflowing into and overwhelming the dishwasher drain. Leaky pipes will need to be replaced, preferably with leak-resistant PVC or PEX pipes.
Contact a plumbing company for more help if your dishwasher leaks.