Why Your Borehole Water Smells Like Eggs and What to Do About It

If your borehole water smells like rotten eggs, the usual suspect is hydrogen sulphide. It can occur naturally underground or be produced by sulphur bacteria in plumbing and storage systems. Either way, it turns a normal tap into a tiny swamp opera.

First, test before treating

Odour alone is not enough. Test for pH, iron, manganese, bacteria and sulphides. The correct treatment depends on whether the problem is dissolved gas, bacterial activity or a combination.

Common fixes

Aeration, oxidation filtration, activated carbon and chlorination can all help, but they must be matched to the water chemistry. Carbon alone may improve smell temporarily while missing the root cause.

Do not ignore it

Beyond being unpleasant, sulphur odours can signal conditions that encourage corrosion or bacterial growth. Treating early keeps tanks, pipes and noses happier.