Why does my water smell like sewage?
A sewage smell is most often bacteria and buildup in the DRAIN — not your water. When it truly is the water, it usually points to hydrogen sulfide or a well contamination issue.
The likely causes
Food and soap build up in the drain and feed odor-causing bacteria. The smell rises as water runs, tricking you into blaming the water.
Sulfur bacteria in the water can smell like sewage as well as rotten eggs.
For private wells, a persistent sewage smell can signal bacterial contamination and should be tested promptly.
Is it dangerous?
If it is the drain, it is a cleaning problem, not a health one. If your water itself smells like sewage — especially from a private well — treat it as a possible contamination issue and get it tested before drinking.
How to tell what it is
Fill a glass, walk to another room, and smell it. Clean water in the glass = the drain is the problem. If the water itself smells, and you are on a well, test for bacteria right away.
The fix
For a drain smell, clean the drain and overflow. For hydrogen sulfide in the water, a whole-house catalytic-carbon system works. For a well, disinfect and retest — and use certified treatment once the source is confirmed.
If the smell is the drain, no water filter will fix it — you are treating the wrong thing.
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