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Water odors & smells:
This article discusses how to identify, diagnose, and cure common odors that may be present in drinking water. We explain how to get rid of or treat stinks, smells, rotten egg odor, sulphur odors in water.
Also described here: How to diagnose the cause of rotten egg sulphur odors in drinking water. What are other common odors in drinking water and what causes them? Health risks associated with some water odors?
How to get rid of other odors in drinking water. Bacteria including iron-bacteria can produce diesel or fuel oil smells in the water, cucumber smells, and even sewage odors in the water supply.
discuss which of these odors may warn of unsanitary conditions.
We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.
"Honey - the Water Smells Funny!" - what are the causes of odors in drinking water?
Although water as a pure compound, H2O, is colorless and odorless, contact with the earth's minerals and our distribution pipes may
impart some flavor and odor characteristics.
The Threshold Odor Test Method
A subjective analysis called the Threshold Odor Test, number 2150b. in Standard Methods
for the Examination of Water and Wastewater, 19th ed., can give us an idea of the strength of the odor as compared to controls of
varying degree of odor concentration.
But how do you interpret what the underlying problem is when your water has a peculiar odor? Just below is a list of articles giving greater detail about the most-common sources of odors in water. At the end of this article you'll find a complete list of water smell & odor diagnosis and correctiion articles.
Cucumber Odors in Water
See see RED STAINS from WATER SUPPLY where we discuss the effects of iron and iron loving bacteria in a water system. Look for orange slime as well as odors of cucumbers, sewage, or fuel oil in the water.
Diesel Fuel Odors in Water
See WATER STAINING CONTAMINANTS where we discuss iron-loving bacteria in the water supply that are able to produce a fuel oil or diesel smell in water.
Methane Odors in Water
Methane from natural sources, from coal mining activities, and possibly from other mining or oil drillling activities can explain the presence of significant, even dangerous levels of methane in well water supplies.
See METHANE GAS SOURCES - possible sources of methane gas in or around buildings? Methane gas (and methane gas production chemicals) in drinking water wells
Sewage Odors in Water
In addition to possible sewage contamination of a well from a nearby failed septic system,
See WATER STAINING CONTAMINANTS where we discuss iron-loving bacteria in the water supply. These bacteria can produce a "sewage" odor or even a "cucumber odor".
Sulphur Odors in Water
Some odors are a little more insidious and require a bit of background knowledge to deal
with them effectively.
If your source water runs through an area where naturally occurring sulfur is
present, some sulfur may dissolve into the water. We provide a diagnostic procedure to track down the source of sulphur smells in water just below.
Some of this dissolved sulfur turns to the gas, hydrogen sulfide, and this can
give the water a rotten egg type smelly odor.
Sulphur odors can also be caused by a failing hot water heater component, or by certain bacteria in the building plumbing system, conditions we also discuss below.
See ANODES & DIP TUBES on WATER HEATERS - a failing water heater or water cylinder anode can produce hydrogen sulfide gas (sulphur smells) in the hot water cylinder and in the building water supply.
See WATER ODOR DIAGNOSIS - SULPHUR- How to get rid of or treat stinks, smells, rotten egg odor, sulphur odors in water. How to diagnose the cause of rotten egg sulphur odors in drinking water. What are other common odors in drinking water and what causes them? Health risks associated with some water odors? How to get rid of other odors in drinking water
See HYDROGEN SULFIDE GAS for a discussion of both sources of sulphur-like smells and the hazards of this gas, including explosion and sewer gas hazards.
See WATER STAINING CONTAMINANTS for an explanation of how iron and manganese bacteria in a water supply system piping or tanks or heaters and water tanks can produce odors including sewage-like smells.
See WELL WATER CONTAMINANT SOURCES for an explanation of how sulphur smells in water can also occur in rivers, lakes, streams, ponds, and can be caused by anoxia and algae which in turn may be caused by high nitrogen from agricultural runoff - a condition we discuss at
UV & Xenon Light Water Disinfection Equipment Odors
Question: petroleum smell in water after installing UV disinfection system
We installed a UV system in residential home. Water source is well water. The water now has a petroleum type odor - even after several days of running the water.
I did see 2 comments re : odor in the FAQ from Oct 2015 but there was no response as to possible cause. Those were from ships. Can you advise? - Anonymous by private email, 2018/01/26
Reply: sources of petroleum smell in water do not include UV light itself
UV - ultraviolet light - disinfection would not itself be an odor source. It is simply a light bulb shining light on water to try to kill many species of bacteria that pass by.
If your well has a petroleum odor I suspect it's originating elsewhere - petroleum (heating oil, gasoline, motor oil) would not not be used in the operation nor installation of a UV light water treatment system.
A diagnostic step would be to collect a water sample upstream from the UV light system or right at the well. Have that tested for petroleum products/residues (as those are found in some well water sources).
Also see WATER STAINING CONTAMINANTS where you will see an explanation that iron-loving bacteria in the water supply are able to produce a fuel oil or diesel smell in water.
Note that a UV water disinfection system will not reduce the iron level in your water.
In contrast with U&V light disinfection, Xenon light disinfection has suffered from some ozone-odor complaints. But ozone would smell more like an "electrical" odor not petroleum. See XENON LAMP OZONE OUTPUT?
Other Odors in Water
See WELL WATER CONTAMINANT SOURCES- what are the common sources of water pollutants and contaminants?
Watch Out: Many serious problems (bacteria, heavy metals, nitrates, radon, and many chemicals) can only be found by laboratory testing of water.
Diagnostic Questions About Odors in Water
Question: My client complains of a "certain smell" in her water but she can't identify it
I've got a client whose weekend home I inspected in 2005. They now have two young children and she's complaining about a "certain" smell in her water. She can't identify the smell.
Rotten eggs? No.
But she smells it on herself and on her children after a bath or shower and says her skin fees dry after a shower.
Another twist. They've got two wells. They switch from one to the other when one gets dry.
This home is in Ancramdale, NY 12503, Columbia County. Pretty rural. Lots of farming and sheep farming, I think.
The client wants me to test both wells. But I'm not confident that any generic water tests will do the job in this case.
I've looked at these two pages and I've got Smith Lab's price sheet in front of me and I think I'm in over my head.
I mean, this could cost them over $1,000 in lab fees alone for the two wells.
Any suggestions? -
Arlene Puentes, ASHI
(Mar 16, 2015) Zyiah said:
My water smells funny
Reply: Starting Point for Chasing Down Unidentified Odors in the Water Supply
Most home inspectors, even men and women who include water testing in their services, to not consider tests for unspecified odors in water as within their scope, and indeed ASHI and other inspection standards exclude these tricky environmental questions.
But you can recommend that your client consult with at least two independent water treatment companies. In her area she can contact Hudson Valley Water Resources - Russ Chapman.
While it's our OPINION that water treatment companies indeed do want to sell water treatment equipment, still they won't make up things that are not there, and they will often agree to inspect a client's water treatment equipment and test her water at no fee.
Also, local water testing laboratories, folks who process a large volume of water samples from their neighborhood, often can tell you (or your client) whether or not they've had odor complaints from other homeowners in the same neighborhood.
Your client might also check these other possibilities:
A more comprehensive starting point for tracking down smells in household water begins
at ODORS IN WATER.
There could be odors coming from a source other than water. She should consult our odor track down approach beginning
at ODORS GASES SMELLS, DIAGNOSIS & CURE, where we consider all common sources of odors in buildings, including water and other systems.
Check the soaps, gels, shampoos, lotions in use because sometimes they may have a role in these complaints
Who smells the odors?
Individual sense of smell varies widely. But if only one person observes an odor or other environmental complaint, some further investigation in an additional direction (besides the building and its neighborhood and its mechanical systems) could be helpful.
Watch out: in some cases, particularly where there were health or aging concerns involved, sometimes these complaints are psychogenic in origin, or on occasion a person might have a health related problem that affects odors and skin sensations. Your client is not elderly, so aging-related health and odor complaints probably wouldn't apply.
But if she is the only person observing the odor complaint, it's worth an effort to sort out this question:
Is the individual observing these odors because s/he has a particularly sensitive sense of smell, or could there be an underlying health or neurological problem that has not been recognized.
If there is even the slightest possibility of the second alternative, the client ought to check with her primary care physician and with that doctor, decide if a referral to a suitable neurologist is in order.
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Scott Bradley, author. Scott Bradley is Laboratory Director for Aquacheck Laboratory, Inc. PO Box 87 05151 1-800-263-9596.
A more brief version of this article appeared in Aquacheck Laboratory's Water Wisdom Tips and Newsletter, Issue # 6, 2007. www.Aquacheck-VT.com offers other water supply tips in its Water Wisdom section.
The laboratory also provides water test kits and offers a free newsletter.
Arlene Puentes, an ASHI member and a licensed home inspector in Kingston, NY, and has served on ASHI national committees as well as HVASHI Chapter President. Ms. Puentes can be contacted at firstname.lastname@example.org
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Crystal Clear Supply provides portable ceramic water filter purifiers and portable reverse osmosis water treatment equipment - see http://www.crystalclearsupply.com/category_s/7.htm
Handbook of Disinfectants and Antiseptics, Joseph M. Ascenzi (Editor), CRC, 1995, ISBN-10: 0824795245 ISBN-13: 978-0824795245 "The evaluation of chemical germicides predates the golden age of microbiology..." -
This well-focused, up-to-date reference details the current medical uses of antiseptics and disinfectants -- particularly in the control of hospital-acquired infections -- presenting methods for evaluating products to obtain regulatory approval and examining chemical, physical, and microbiological properties as well as the toxicology of the most widely used commercial chemicals.
Principles and Practice of Disinfection, Preservation and Sterilization (Hardcover)
by A. D. Russell (Editor), W. B. Hugo (Editor), G. A. J. Ayliffe (Editor), Blackwell Science, 2004. ISBN-10: 1405101997, ISBN-13: 978-1405101998.
"This superb book is the best of its kind available and one that will undoubtedly be useful, if not essential, to workers in a variety of industries. Thirty-one distinguished specialists deal comprehensively with the subject matter indicated by the title ... The book is produced with care, is very readable with useful selected references at the end of each chapter and an excellent index. It is an essential source book for everyone interested in this field. For pharmacy undergraduates, it will complement the excellent text on pharmaceutical microbiology by two of the present editors."
The Pharmaceutical Journal: "This is an excellent book. It deals comprehensively and authoritatively with its subject with contributions from 31 distinguished specialists. There is a great deal to interest all those involved in hospital infection ... This book is exceptionally well laid out. There are well chosen references for each chapter and an excellent index. It is highly recommended." The Journal of Hospital Infection.: "The editors and authors must be congratulated for this excellent treatise on nonantibiotic antimicrobial measures in hospitals and industry ... The publication is highly recommended to hospital and research personnel, especially to clinical microbiologists, infection-control and environmental-safety specialists, pharmacists, and dieticians."
New England Journal of Medicine: City Hospital, Birmingham, UK. Covers the many methods of the elimination or prevention of microbial growth. Provides an historical overview, descriptions of the types of antimicrobial agents, factors affecting efficacy, evaluation methods, and types of resistance. Features sterilization methods, and more. Previous edition: c1999. DNLM: Sterilization--methods.
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: email@example.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors. Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
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The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume.
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