Part of the Water Wisdom Seriesfor

Home Inspectorsby:

Scott J. BradleyAquacheck Laboratory, Inc.

1-800-263-9596

Odors In Drinking WaterWhat causes odors in our Drinking Water?Is it dangerous to our health?How can we get rid of or filter out odors in our

water?Is there a scientific way to measure odor?What should a Home Inspector know about odors

in drinking water? Remember that taste and odor are incontrovertably linked to each other.

news.bbc.co.uk

Home Inspector – Odor in WaterThere are many things that can cause odors

in our water.Pure, clean water is odorless and colorless.One of the main causes of odor in drinking

water is from sulfur as hydrogen sulfide, (H2S

-). In almost all residential situations, hydrogen

sulfide is not a major health concern.It can make the water objectionable because

it imparts a “rotten egg” smell to water.

Home Inspector – “Nosing-Around”

What happens when you smell sulfur, or rotten egg odors strongly in one room in the home, but not nearly as much or at all in the other rooms?

Often times, this is caused by a “dead-leg” in the plumbing. A water pipe that was cut and capped –looks like the letter “T”.

This can trap and hold bacteria such as Desulfovibriole.These sulfur related bacteria can increase odors by metabolizing the

available sulfur in the water. pic: MSN.COM

Home Inspector – Odor TreatmentIf you smell sulfur odors in one part of the home and not

another, than it is indicative of trapped sulfur-related bacteria. (Make sure drain pipe traps have water as well).

These odors can be removed by simply eliminating the dead leg. Chlorination does not usually work, because water does not circulate in the dead leg and chlorine can’t get in there very well.

An activated charcoal filter will also remove sulfur odors.If the problem is extreme, and coming from the source,

the water can be agitated (bubbler) to release the H2S-

which is then blown to the exterior of the home.

Home Inspector: Testing for OdorsThe Threshold Odor Test can be performed

on drinking water.The subject water is compared to other

waters of increasing odor values.A number based on this comparison is

assigned to the subject water.You will get a number from 1 (lowest) to 3,

(highest).This test is one of the very few subjective

analysis performed with drinking water.

Home Inspector- Other OdorsThere are some other common odors in water.If water smell and tastes “musty, swampy, flat, or

even salty,” it may have too much chloride.Anaboena type bacteria can impart a “fishy” odor.Algae can make the water taste and smell like

chlorophyll, and algae.Metals can give bitter or slightly astringent odors.Dirty smelling water may mean too much silt, or that

the cone of depression in the well has collapsed.If you have a dug well and the water smells foul, go to

the well – in all likely hood there is a dead critter in the well!

Home Inspector – Cleaning Up!Chlorine is a good combatant when it comes to

fighting odors. (Cl2)Chlorine will dissolve most organic material in the

water while disinfecting to reduce bacteria odor.

If the chlorine smell is objectionable, use an activated charcoal filter to remove the chlorine odor and flavor.

When chlorine comes in contact with certain organic molecules, trihalomethanes, or disinfection byproducts can be formed.

Home Inspectors Series: Odors in Drinking Water

I hope you have enjoyed this issue of Water Wisdom for Home Inspectors, brought to you

as a courtesy learning tool from Scott J. Bradley at

Aquacheck Laboratory, Inc.

http://www.aquacheck-vt.com

1-800-263-9596