The answer to 'my sump pump smells bad' is that a smelly sump pump is often caused by bacteria growth, debris buildup, or a failing pump. This can lead to unpleasant odors and potential health issues if left unchecked. Common symptoms include a foul, rotten egg-like smell and slime or debris in the sump pit.
Some common solutions include cleaning the sump pit, disinfecting the pump, and replacing the pump if it's old or damaged. Regular maintenance like this can help prevent smells and keep your sump pump working properly. However, if the issue persists or you're unsure of the cause, it's best to call a professional plumber to diagnose and fix the problem.