Finding a pool of dirty standing water in the bottom tub of your dishwasher at the end of a cycle is a very common issue. Fortunately, it is usually caused by simple food blockages in the filter or drain line rather than a mechanical failure.
Common Drainage Blockage Points
Dishwashers rely on gravity loops and a small drain pump to exhaust waste water. Check these 3 points first:
- The Mesh Filter: Located in the center bottom of the dishwasher tub. It collects food particles and can clog easily if not rinsed regularly.
- The Garbage Disposal Connection: If you recently installed a new garbage disposal, ensure the knock-out plug inside the disposal tube was removed. If left in place, water cannot drain out.
- The Air Gap / High Loop: If the drain hose under the sink lacks a high loop or air gap, sink wastewater can flow backwards into the dishwasher.
How to Clear Dishwasher standing water
- Rinse the Filter: Rotate the filter lock counter-clockwise, pull the mesh cup out, and clean it under hot running water with an old toothbrush.
- Inspect the Drain Valve & Hose: Straighten any kinks in the hose under the sink cabinet.
- Check the Pump Impeller: Access the pump casing underneath the filter assembly. Carefully feel for any hard seeds or glass shards blocking the impeller from spinning.
⚠️ WARNING: Use caution when clearing pump impellers. Shards of broken drinking glasses frequently wash down and jam the pump.
