Smell in water is the result of various types organic and inorganic materials in water. They can be man-made such as chlorine and ammonia or naturally occurring such as Sulphur and iron. The result however is the same, the water SMELLS! So lets break it down. What compounds account for some of the most common water smell complaints.
Chlorine: Chlorine is added to municipal water treatment facilities to kill harmful viruses and bacteria including coliforms and e.coli. The unpleasant result of this added chemical is the smell it produces in our drinking water supply. When the smell of “bleach” is present in your drinking water it is the result of being treated with too much chlorine. This is often dependent on the proximity of your home in relation to the water treatment facility in your area. The chlorine also reacts with other chemicals in the water to form byproducts such as trihalomethanes which not only create a foul smell, but are also harmful to your health.
Hydrogen Sulphide : Most commonly referred to as sulphur, this naturally occurring gas produces a rotten egg smell. If sulphur is present in your water supply in high levels the smell of rotten eggs will be noticeable as soon as you walk into your home. Lower levels of sulphur will be most prominent on both your hot and cold water supply. If the smell is ONLY present on the hot water supply, the likely cause of the smell is sulphur reducing bacteria (SRB). SRB’s are naturally occurring in well water and are usually not a concern, however when they react with the heat of your hot water tank or remain stagnant in your water softener or backwashing system they create an unpleasant odour resulting from an overgrowth of the sulphur reducing bacteria. Although Sulphur and Sulphur reducing bacteria product an unpleasant smell they are not harmful to your health. However hydrogen sulphide can damage pipes as it corrodes different types of metals and can cause black stains on silverware and plumbing fixtures.
Organic Compounds: Organic materials in water can be of many types and have many origins. When water temperature increase the heat activates the organic compounds thereby producing a MUSTY, EARTHY smell. This is why the musty smell is most commonly experienced seasonally during the warmer summer months The smell is caused by the decay of naturally occurring vegetation. These decay compounds are called lignins or tannins. Although the smell is not harmful, it will be unpleasant and may change the taste of food or beverages made with untreated water.