Sewer or septic gas odor diagnosis & cure: our septic or sewer gas odor cure article series beginning here describes how to diagnose, find, and cure odors in buildings including septic or sewage or sewer gas smells or "gas odors" in buildings with a focus on homes with a private onsite septic tank but including tips for owners whose home is connected to a sewer system as well.
What makes the smell in sewer gas?
Sewer gases are more than an obnoxious odor. They can be dangerous.
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Sewer gases also probably contain hydrogen sulfide gas (H2S). In addition some writers opine that there are possible
health hazards from sewer gas exposure, such as a bacterial infection of the sinuses (which can occur due to any sinus irritation).
Depending on the sewer gas source and other factors such as humidity and building
and weather conditions, mold spores may also be present in sewer gases
How do you measure or check sewer gases to see if the smell we have coming out of our bathroom is a gas or just a smell? and does it measure the smell/gas to see if its at a dangerous level? - K.E.
Hello, I read the article on sewer odors, it was very helpful, I would just like to know what service I should contact to diagnose the exact problem? Do I call a plumbing service, or a duct work service? I am in the dark as to who can actually, accurately, diagnose. - Anonymous by private email 2016/09/19
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem. That said, here are some things to consider:
What steps are useful to avoid smelling (or blowing up from) the gases that form and naturally want to escape from residential septic systems? How can we diagnose sewer odors at a building site to determine if it's a venting problem, a failure of the septic system, or the failure of a neighbor's septic system, or perhaps even a leak from a fuel gas line or appliance?
Watch out: both hydrogen sulfide gas and methane gas are potentially explosive
Check for leaks in fuel gas lines and appliances: the mercaptan put into LP gas and natural gas is inserted there by the gas company as a safety feature so that people may notice that they have a dangerous (explosive) gas leak in their home. Some people may confuse this odor with a septic tank gas odor.
The photo shows black stains on copper tubing at the flare fitting connecting an LP gas line to a shutoff valve. Some service technicians
point to stains on piping as an evidence of a possible chronic leak in the gas line at this point.
If you suspect that there is a fuel gas leak in a home, or even if there is a gas odor from any source, leave the building and call your fire department for assistance.
Even so simple a task as dialing a telephone could provide a dangerous spark and cause an explosion. In New York City there seems to be about one terrible gas explosion
a year that is blamed on either a fuel gas leak or a sewer gas leak which accumulated explosive gas in a building.
Also see Gas Piping and Tank Defects.
Observe septic system safety procedures When opening a septic tank for service or repair, observe the safety precautions I describe earlier on this web page.
We have had reports of a septic pumper having his face burned by exploding methane when he lit a cigarette during pumping, a homeowner who generated an explosion of the septic tank that rocked the entire neighborhood when he built a brush fire atop the septic tank.
We have also read of deaths occurring when untrained service people entered a pumped-out septic tank to inspect it.
Also Check for the presence of Chinese drywall: because it is easy to mistake other sulphur odors for sewer gas, if your building was built or remodeled between 2001 and 2007, especially in 2006 or 2007,
CHINESE DRYWALL HAZARDS - the corrosive outgassing of Chinese drywall can make smoke detectors and carbon monoxide detectors unsafe and it may also be an indoor air quality concern in some buildings.
At SEPTIC & CESSPOOL SAFETY we explain that gases produced in a septic tank are dangerous, as a potential source of explosion and as a cause of death by asphyxiation if someone falls into or deliberately enters a septic tank.
In low concentrations (less than 0.15 mg per liter), hydrogen sulfide may produce inflammation of the eyes, nose, and throat if breathed for periods of 1/2 to 1 hour. Higher concentrations (0.75 mg per liter or greater) are rapidly fatal, presumably by combination of the hydrogen sulfide with the respiratory tissue pigments and the subsequent paralysis of the respiratory center.
The symptoms depend upon the concentration of the gas. At the lowest concentrations, the effects are chiefly on the eyes; that is, conjunctivitis, swollen eyelids, itchiness, smarting, pain, photophobia, and blurring of vision. At higher concentrations, respiratory tract symptoms are more pronounced.
Rhinitis, pharyngitis, laryngitis, and bronchitis may occur. Pulmonary edema may result. At very high concentrations, unconsciousness, convulsions, and cessation of respiration rapidly develop.
Watch out: higher concentrations of hydrogen sulfide (H2S) gas (0.75 mg per liter or greater) are rapidly fatal, presumably by combination of the hydrogen sulfide with the respiratory tissue pigments and the subsequent paralysis of the respiratory center.
Details about hydrogen sulfide gas are at HYDROGEN SULFIDE GAS where we discuss the effects of exposure to H2S and H2S exposure limits.
The original discussion at this location has been moved to a separate article
at SEWER SEPTIC GAS CONDUIT LEAKS Through Electrical Conduit? - Separate article
The original discussion at this location has also been moved to a separate article now
at - SEWER SEPTIC ODORS in HVAC DUCTS
see BIO-FUEL PRODUCTION & USE for our full article on this topic.
A few readers have asked if they could just capture methane gas from their septic tank to use as a household fuel for heating, cooking, or gas lighting. And there are septic-tank-like systems designed for that purpose, but as we warn below, don't just try hooking up your septic tank to a gas burner.
Indeed biogas can be produced, captured, compressed (like natural gas) and used as a fuel, including powering vehicles.
See BIODIESEL HEATING FUELS for information about using biodiesel in oil burners designed for heating appliances: boilers, furnaces, water heaters
Continue reading at SEWER GAS ODORS in COLD WEATHER or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES.
Or see ODORS GASES SMELLS, DIAGNOSIS & CURE - home
Or see ODORS, PLUMBING SYSTEM - home
Or see SEWER GAS ODOR REMEDIES
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Our rent house is right next to an alley. There's a manhole there from which emanates a strong sewage smell. This is an old neighborhood with old clay pipes that we suspect are broken underground, but the city will not dig them up and replace them unless there is standing water.
The smell permeates the air outside the house and is pumped in through all ac vents into our home. Every couple of months the city will drop a "scent cake" out there, which does nothing to help. I'm 6 months pregnant and worried about any health risks this may bring to my infant. I'm at my wit's end trying to get the city's cooperation! Help! - Rachel
Dropping a deodorant into a manhole over a sewer system is not going to correct an ongoing sewer gas leak or odor problem. You may want to contact an official in your city's health department, ask them to visit the site during an odorous time and to agree to have the problem diagnosed and corrected.
We have an upstairs toilet that leaks that we haven't used in some time. My husband took it up four days ago and left the drain hole open. Are we in danger due to methane gas. It smells bad in that part of the house. - Stacy
In particular if your home is connected to a public sewer and your house lacks a trap at the main sewer line exit point from the building, you could get a lot of sewer gas backup in the building. Methane in sewer gas is explosive if it reaches the right concentration.
Any plumbing supplier or even home depot will sell you a toilet waste line plug that can close off that opening. In an emergency I wrap a rag in a plastic bag and shove it into the hole - just don't push it in so far that you can't get it back out.
We have a horrible oder coming from the basement. We believe there might be a septic tank abandoned in our property. Would old un-used septic tank cause odor to the house? - Winnie Wong
No, not normally. But for safety you should find the tank and make sure that it is properly abandoned such as by filling-in. If someone falls into a septic tank they're likey to die in minutes.
For the last 5 months we have been in this home there has been a horrible smell. I have had tampa gas, Roto Rooter, mold people, handmen, rat control, air conditioning fellow, and tampa sewer.
They all point to sewer. We have had smoke tests as well. We feel it is a breach under the slab and it is prevalent in one bathroom and the air conditioner/fan circulates it throughout the house. It was very bad on days it rained but now it is unbarable on dry days. It is getting worse and wakes us from our sleep. It can come and go but if we turn the furnace face on automatic the odor will build.
We feel the only thing left to do is scope the lines but landlord is now checking the environmental issues like the ponds in the area and the levels of the water for swamp gas. Please help us. 813 994 3391.
I agree that for smells that originate in the building and given the people who have already advised you, using a camera to look for a broken sewer line makes sense.
Your observation that odors are worse when the furnace is running increases the worry of pulling dangerous sewer gass into the home.
Our ODORS GASES SMELLS, DIAGNOSIS & CURE article series (links at the "More Reading" links at the bottom of this article ) includes other suggestions for tracking down odors.
I am smelling something horrible coming from the kitchen drains, our utility room and toilet area. The smell actually took my breath away a couple of times like my throat was closing. The only smell that I can say is similar is the smell of bleach. That super strong odor. Could it be the septic? - Wendy
A bleach smell would not be something I'd expect to find coming from a septic system. If you trust your sense of smell, I'd be looking for a chemical spill or something having been poured down the drains.
I rent an apartment and have noticed what I suspect to be biofilm in nature. First, the drains in the double kitchen stainless steel sink, bathroom sink, and bathtub seem to be overgrowing with black slime. I clean all areas on a regular basis with a bleach based cleanser.
My next problem concerns the toilet (which I suspect might have a biofilm issue as well?). Every few days or so, the toilet "burps" (almost like air pressure purging back into the toilet) and then it bubbles followed by a terrible odor. If you think it is an issue concerning biofilm, is there any way I can control this myself with some type of disinfectant by pouring it down each drain. Any info you can provide would be greatly appreciated.
I'm not sure what you have in mind with biofilm, but your description sounds like possibly a mold growth, more likely an algae growth. If cleaning and disinfecting are not curing that problem I suspect the water supply.
The burping toilet suggest to me a partially blocked main building drain, perhaps at some distance from the toilet and/or a building vent piping problem. I suspect that drain cleaning for blockage is in your future.
I have a smelly bathroom and I just replaced the wax seal and sealed the bowl, cleard any obstuction from the roof vent with a power hose and still I have a smell. what's next.? - Leo
We recently had a new septic system put in. Ever since we had it installed, we now get occasionally, a very strong sewer gas smell in our bathroom. How do we stop this odor from comming in? It never happened with the old system. - Val
I have 2 bathrooms on 2 different levels of the house. I am getting intermittent septic odor smells backinging up into both bathrooms. It happens in good weather and bad. It's not every day but when it happens it's usually for at least a week at a time. I had the tank drained,, the toilets checked for leaky seals, the vent pipe checked for blockage. No one can diagnose the problem but it it dangerous and I need help. What other measures can I use to diagnose the problem? - Lynne
In starting with the easy and low cost bath smell cure steps,
- check for dry traps at unused fixtures
- replace the toilet wax ring,
- check ceilings below the bathroom for signs of leakage
- listen to nearby drains when the toilet flushes - gurgling can indicater a clogged main drain or inadequate plumbing vents; if so, investigate and cure drain blockages, or in some cases, a "blockage" that occurs in the waste piping because the septic tank and drainfield are backing up
- ask your plumber to inspect the plumbing vent system for proper layout, size, routing, connections, and termination
- pressure test the vent system for leaks that may be hidden in walls, floors, ceilings
Mysterious Sewer odor solved!!!
For the past 2 years we have had a sewer odor in my basement within 5 minutes after a long shower or my kids using the tub. I have had a half dozen plumbers in, we tore apart the basement ceiling and walls in search of the smell.. no luck! We did smoke tests... No Luck!! we flooded the waste pipes with water... No luck...
THEN after a 3 day 8 hrs a day plumber marathon (over $2k) and the rest of my walls torn down, and we dug up my pipes outside my house and my cesspool.
We found it. The rubber gasket after the house trap that connects the cast iron 5 foot pipe to the outside of my house and the metal house trap was venting a small amount of gas ONLY when water was flowing through it...(hence no smoke during that test) We proved it with a lighter (NOT RECOMMENDED) but when water flows in large volumes, such as a tub draining... the flame flickers and continues to do so for a seconds after the large water flow.. note it does not happen if a toilet flushes.
Temporary fix was to put some Mortite around the pipe and gasket... 5 days no smell.. Now we have 2 choices, cut out the main trap and put in new pipes, or... just tar the gasket....( a 10 dollar fix) - Paul, Long Island, NY 2/1/12
Thanks Paul, this experience report will help other readers. - Ed.
We have been having sewer smell in the storage room underneath our staircase for 2 years. We tried a lot of things including buying a combustible gas detector.
The 0.01ppm detector detected nothing. But our nose can still smell it. Occasionally we had smelled the same in the adjcent bathroom (they share a wall). But it wasn't consistent and not always. It's so misterious and we are desperate to get it resolved. Any help/advice will be highly appreciated!!! - Still Searching 3/11/12
Try the diagnostic suggestions at ODOR DIAGNOSIS CHECKLIST, PROCEDURE
I never noticed this problem til after the addition of a second line to our concrete tank. now sewewr air comes in the house (I believe in the kitchen area) we tried to check roof vents, had an s trap put in kitchen sinks (they had none). I also suspect the kitchen sink is not tied in to the vent (Small high ceiling log cabin with kitchen sink away from other plumbing... but never noticed trouble before the new line to garage was added. Any ideas? - Kris 6/5/12
Kris I may have misunderstood, but "S" traps are not used in new construction as they easily lose the water in the trap base, thus permitting sewer gases to enter the building through the fixture drain.
I suspect your sink drain is not properly nor adequately vented. You may be able to fix the problem by installing a proper P-trap and if there is no vent line available and the local building department permits, you can install a vacuum breaker vent at the sink drain.
Our house was listed for sale last week.
This week we noticed a crack in the cast iron sewer pipe and had it replaced by professional plumbers. A lingering miasma would certainly keep prospective buyers at bay. We've ventilated the basement and have fans and dehumidifiers at work. We also tried vinegar solutions, but to no avail.
Any further advice would be greatly appreciated. - Vicki LeClair 6/29/12
Vicki I hate when that happens - sewer leaks. It's possible that the lingering miasma (a sewage smell) is because there was not just a cracked pipe but sewage leakage into the building. ANd depending on the cause of the crack, don't rule out the possibility that there are other cracked sections , p0erhaps in inaccessible or hard to see areas.
Track the odor to its strongest area - if you had just the one leak that's helpful.
Then investigate where sewage water may have flowed. It may be necessary to further remove/clean wall cavities & clean flooring. If carpeting was involved, remove it.
Thank you for your advice DanJoeFriedman.
Appreciate your taking the time.
We'll investigate further.
If the copper pipes are black due to long term exposure (2 years) to sewer gas, do the copper pipes affected all need to be replaced, or can they be cleaned, and if so, with what products? The source of the sewer gas has bee rectified. - Gail Rose 8/13/12
Copper drain piping that is not actually corroded to risk leakage does not need to be replaced nor cleaned, but you should be sure that you don't have any remaining sewer gas leaks.
Please help! I have a 115 year old home that I have lived in for 12 years. Recently, approx 6 weeks ago, the town was doing work on the sewer lines located on the street that I live on. One afternoon, end of a work day i returned home to an extremely rancid smell that permeated throughout the entire house. The town has since inspected and said they could not find any reason that it should happen. HERE IS WHERE IT GETS WEIRD. The smell shows up daily and seems to be time specific each day from 3:30 pm to around 5:30 pm?! In addition to the towns inspection, we have had two different plumbers inspect from top to bottom. Any suggestions would be sincerely appreciated. - Anonymous 8/19/12
Try the diagnostic suggestions at ODOR DIAGNOSIS CHECKLIST, PROCEDURE where you'll see that we suggest looking for things to correlate with smells that appear at particular times or seasons, such as
- operation of nearby businesses or activities
- operation of equipment
I am looking for some advice. We have just moved in a brand new home. At first we could smell a strong sulphur odor in our water. We had a centaur filter put in, which took the smell away immediately. I then noticed sewer gas smell mainly in our 2nd floor laundry room, but also the 1st floor mudroom (utility sink.) I was told to add water to the sinks and floor drains and mineral oil to the floor drains as well. I did this and we still have the sewer gas odor, especially after I do laundry.
My dryer which was working perfectly before the move, now takes 3 cycles to dry a load of clothes. It is after running it, that the smell worsens. FYI the dryer is not vented to the outside wall, but apparently into the stack and up through the roof through a static vent. I would love some ideas as to what it could be as we are now having burning noses and throats and headaches. Thanks so much in advance. - Heather 9/12/12
Let's separate things to not get too confused. Odors in the water supply - if that's where they are coming from, won't affect how long it takes a clothes dryer to dry stuff. But odors in the water do need to be diagnosed and most likely corrected. There are treatment systems for sulphur if that's the problem.
Separately, investigate the dryer vent system for length, bends, blockage - as longer dry time also can be an indication of a FIRE HAZARD as when a dryer has trouble venting it not only takes longer to dry the clothes but it also runs hotter.
An update. The plumbers came and did a smoke drop test. There were no evident leaks in there. The builder sent out someone the next day, who found the dryer vent on the roof was totally blocked with a mat of lint. He removed that and the wire mesh that was left in place. They raised the vent stack to over 3 feet. I let the house "air out" for 3 days then decided yesterday, that we needed to try out the AC, as our symptoms increase dramatically when it is on. Within 10 minutes of it being on, we started again, with burning eyes and throat with headache.
The dog even had clear drainage from his nose. Today the HVAC technician was here to look at both the unit in the attic and the one in the basement. He thought that it could be the oil that is applied at the factory, that was not burned off. He told me to run the heat for as long as I could, which I did.
We are getting the vents and units cleaned tomorrow. He then told me to run the AC after and see if we continued to have symptoms. Everything I have read points me to the fact that we are inhaling either VOCs or formaldehyde. The house is brand new, and I would not expect "sick building syndrome" in a brand new home. I have never reacted this way to anything before. I am at a loss. Also, there is no attic fan.
Do you think we could benefit from having one placed? Thank you so much for the help. - Heather
Heather, based upon your comments - you are a good candidate for an air quality test. An environmental testing co. could take samples from your home and have them analyzed for gas levels . turnaround would be a week or so and would identify higher than standard levels in you home. Possible sources (other than those you've mentioned)are : paint off gassing, hardwood floor finish, carpet fibers, cabinet plywood or particle board, particle board carpet base, among others. Any new home will have a period of off gassing from finish materials . higher indoor temperatures accelerate the gassing effects. - DF
Comment from reader NCBuilder:
Heather, your builder should also be able to provide EPA data sheets from manufacturers of finish materials used in your home : paints, varnishes, floor finishes, catalyzed laquer (cabinets), carpet fibers, etc. These would be a big help if you indeed go the air quality sampling route.
Thanks NCBuilder - Ed.
My home has a foul smell. In both bathrooms, sinks, and main drain in the basement. I noticed today that the main waste stack has two 90 degrees on it, is that ok? Could that be contributing to my smell? I live in St. Louis, MO - Mary 10/30/2012
If the plumbing vent (main waste stack) is unchanged, that is if that double bend has always been present and the odors are new, I doubt that it's the problem. But I'd agree that a blocked or leaky plumbing vent system is often an odor source.
Is there an electrical motor that helps move the sewage from the toilet through the pipes and into the septic tank? And, what moves the water out the leach lines. i had noticed a noise after running water either kitchen or bathroom or flushing about 2 months ago, and now I believe I smell some gases - more like "sitting water" smells in the house. It is not specifically around the toilet or drains. I also noticed the 45 foot leach lines are still watering the grass in the pasture, but not to the end of the lines as they once did. My house is 45 years old, and I purchased it about 17 years ago. - Phyllis 11/17/12
See SEWAGE PUMPS for a starting point. There are several types of pumps and systems - sewage ejector pumps or sewage grinder pumps for two.
I have two problems. One: Sewer gases smells are coming from my bathroom sinks, one upstairs and one downstairs. It is not all the time but at least 80% of the time. I my landlord but is just said that this is a problems that lots of people have and nothing is wrong. He never actually investigated. The secoond problem: My dishwasher is emitting some type of datk gummy residue all over my dishes. In addition, I also notice a dark powder like substance on the outside of the dryer at the bottom.
My landlord said that these problems come from food particles left on dishes. I always use a brush to wash my dishes and I know that this is not the cause. It appears that there is a build up of some kind and then it is all over everthing. I wonder if the two problems are related and if this is residue from the sewer. I am a senior citizen and recently my daughter and her 8 month old baby living here. I am concerned for our safety. I have some medical issues that never occuted before I moved her a few years ago. such as extreme fatigue and some times headaches. Could you pleasae give some advise. How can I get these things tested without it being too costly? - Barbara 12/1/12
Your landlord is wrong that sewer gases are harmless; the risks are of a methane or hydrogen suflide gas explosion, and from chronic exposure there are potential health effects (citations are in the references at the end of this article).
While it's common to detect slight odors and low gas levels right at sink drains if you are smelling those odors in the occupied space, that is not normal and needs to be investigated and corrected.
II have rented this moble home for 5 months now and my 22 month old baby and the rest of the family have been sick for a while. Even after cleaning really good. About a week ago i had a pipe freeze and bust ao called the plumber while fixing the busted pipe he said that my drain pipe was not hooked up to septic but had been draining under the house. The pipe has been fixed but landlords have not had anyone come clean under house. Is that something to worry about? - S Susan 1/29/2013
Without inspecting and testing we don't actually know what hazards are present in your home nor if the unsanitary conditions under the home are showing up indoors. But nevertheless, you are describing an unhealthy condition that almost surely violates local building and plumbing codes in your area.
Watch out: bacterial hazards, sewer gas hazards, methane and hydrogen sulfide gas hazards are all potential health hazards and where those gases accumulate indoors they can even be an explosion hazard. Notify your landlord in writing of these conditions and ask for immediate repair and also cleaning and sanitizing at your home.
My house has attached semi-outdoors laundry with a toilet and a sink, but the leak comes from the wall next to a bathroom. The water that leaks looks clear but stinks like sewer. Toilets are burping with air bubbles backing up into restrooms. What could be wrong? - John 2/23/13
You are describing what sounds like a blocked drain and backup leakage into the building. Further investigation, repair, and sanitizing are almost certainly needed.
(Mar 14, 2014) Susan Sandlin said:
The following link does not appear to be functional: "There is a Septic Tank Odor Coming from a Vent Under My Air Conditioner." Unfortunately, this is the problem that we seem to be having. A very putrid odor is blown out of the supply vents when the air conditioner is on. We are trying to determine the cause and what needs to be done to fix it, as it is such a foul smell that I don't believe we will be able to stay in the house if the air conditioner is needed.
(July 10, 2014) Charles Armstrong said:
Smell in Utility Rm. I have my septic cleaned out, I've cut holes in walls for dead mice. I,ve moved my washer out into the garage, I,ve stuffed rages down my washer stand pipe and my sink in the utility rm. Is their an odor sniffer that I can use to track down the smell?
Susan you've caught me amid moving some topics around, but you can read the A/C odor comments in the FAQS discussion a above. Just click on "Click to Show or Hide FAQs" and you'll find our discussion starting at
Question: There is a Septic Tank Odor Coming from a Vent Under My Air Conditioner: Who do I Call?
Let me know what you think and what questions remain.
And consider a dead animal in the air handler or ductwork - if that's the case the risk is more than odor as health concerns could be present.
In the More Reading links just above click on
TESTS for SEWER GAS INDOORS
and read about using the TIF8800 combustible gas analyzer
(Apr 19, 2014) katherine said:
Early morning and night time air odours, Pungent, sulphurous, nauseating,-could this be bore water especially with no rain for months. In WA.
Katherine, after you've reviewed the steps above about how to find a sewer gas odour source, it may help to combine the visual inspection steps with the checklist described at inspectapedia.com/odor_diagnosis/Odor_Diagnosis_Checklist.php
(Apr 21, 2014) don said:
I have hydrogen sulphide smell in my sewer line and have identified but have yet to see anyone's help to remove the problem.. what do I put in my sewer drains and lines.
I don't think that ANY additive, chemical, or treatment poured into the sewer drains and lines is likely to be effective, and it may be harmful to the drainfield and will be illegal in many jurisdictions if you are connected to a private septic system.
Rather we want to track down the odor cause and fix that. Examples are defects in the plumbing vent system, leaks in the sewer piping, or a backing-up main building drain, or if you are connected to a private septic system, a backing up or clogged septic system.
(Apr 23, 2014) Anonymous said:
thanks for your response. I have a lagoon system, installed a new mobile home in dec 2013, the odor started about mid Jan while wife was doing laundry, I understood bleach would clear up pipes but no luck, strong smell from vent pipes on roof, strong smell around out side seems to come from vent lines, have replaced all vent line check valves to P traps but no change in odor, when washing machine is running seems to be worse, if it's machine how do I rid this from machine... thanks for any input as odor is quite strong at times.....don
We discuss lagoon septic systems at inspectapedia.com/septic/Lagoon-Septic-Systems.php - take a look.
Some odors are normal around a septic lagoon treatment area, but others are not, as you'll see in that article.
Bleach will not fix anything in this case and if used in quantity it may harm the septic system.
(May 2, 2014) Don said:
After much searching you can rid the hydrogen suphur smell, try using hydrogen peroxide. I do a week ago and no smell left. I put a bottle in each drain, the washing machine and each vent line on the roof. so my original question is answered and hope this helps anyone else with this problem.
(May 3, 2014) Anonymous said:
Watch out: Don's advice is dangerous. It treats the smell symptom not the cause. If sewer gas is entering a building there is risk of an explosion.
(May 10, 2014) Jessica said:
I clean in very old buildings with very old pipes. I am told to put water down the drains to take care of this problem. I have seven buildings but two in particular that horrible fumes come out on windy and hot days. Rust also comes out of the sink and toilets when the sprinkler pipes are flushed making the toilet & urinal water brown. I am sensitive to smells because of restrited airway disease. I know I am in the wrong business and I did get sick at my work in a different area in the past. This building was checked out on the third day of the horrible fumes and of course by then, they has abated. I did not put water in the trap on purpose because this not what all the fumes were from. I wanted them to see that was not the problem.
This building and it's pipes are from the late 50's early 60's. I was told the pipes are broken up under the building and obviously very old by some of the older Craft employees. The fumes are in two of the four bathrooms on one side and the custodial closet. In the custodial closet there is an underground that is coverd and that room reeks too. Because the third day the fumes were not there, I looked like I didn't know what I was talking about.
I did get sick on top of my restrictive airway disease and that scared me even more. I came down with horrible head cold and headaches. Making my breathing even more difficult. What would make the fumes come and go? Is it dangerous? Can it be fixed? Would it cause the added effects that I mentioned? I know alot of questions but I have to have my ducks in a row when I return to work from being sick. Thank you so much for yur time.
There is more building specific information that one would need to give a reliable diagnostic answer to what's going on. Rusty water is not necessarily dangerous; but sewer gas, if that's entering the building, could be quite dangerous both as a health hazard and an explosion hazard - IF that is what is present. The causes are not what one could diagnose from just a text message, though our articles on sewer gas odors list many common causes such as blocked drains and defective plumbing vents.
If you see open drain cleanouts, sewage spills, leaky pipes, or smell what you think is sewer gas (sewage smell or sulphur or methane gas smell) you should report those to appropriate building management as safety and health hazards for everyone.
(May 27, 2014) Megan said:
Hi I am worried about my sons health we have a garage built in to a room when we moved in well the owners had a septic tank in the back... and well we have these horrible smells threw out the day. and I was just reading and it contains methane gases. what is the best way to fix the problems cause I am worried about the gaes and my sons health
Megan there ought not be sewer gases invading the home from a septic tank; the odor may indicate that there is a backup at the tank, leaks at the tank, or a failing drainfield. I'd try to track own the odor more accurately.
If the septic tank is in use the system will need diagnosis & possibly repair.
if the septic system is not in use it needs to be emptied, cleaned, and filled-in.
(May 28, 2014) Dee said:
After having my septic tank empty I have a strong odor coming up from the bathroom shower when you run water
Sounds as if there might be dry traps in other fixtures or a leaky vent piping. Cleaning a septic tank ought not create an odor problem in the building.
(June 2, 2014) Damali Robertson said:
I recently had laminate floors installed in my bathrooms. Since the installation, one of my bathrooms has had a very strange odor (that comes and goes). Had a plumber come out on a day when it wasn't that bad. He cleared hair out of a drain in one of the sinks. But the smell came back and again comes in and out. One the days it is present, it is really strong. In trying to figure it out, came across this article. The contractors removed the toilet to lay the flooring. Is there a possible connection and what is the best next step to take?
CHeck for odors coming from the flooring itself or its adhesive.
Check for a bad toilet wax ring seal.
(July 5, 2014) Val said:
My bathroom sink (and, recently, my bathtub) smells like sewer whenever I run the water, be it hot or cold. It doesn't smell like rotten eggs; more like poo. There is no gurgling sound and both drain properly. The sink is new, as well as the P trap. I opened the P trap and the water smells like sewer, like, really bad. The washer drain, also located in the bathroom, is fine, as well as the kitchen sink.
I replaced the bathroom sink for two reasons: this odor and the fact that it was old, hoping this will solve the problem. It didn't. When I replaced the sink I used an auger to clean the drain as well as I could. There was no abnormal smell coming from the drain at that time. This puzzles me because I don't understand why it doesn't smell when the p-trap and the other components are removed but does when they're installed... Also, it doesn't smell when the water is turned off and it is present regardless of the weather or season.
I live in a city so my water drains into the city main. Also, I live on the top floor of a duplex. The first floor doesn't have this issue. I suspected it might be the toilet that sucks the water from the p trap when i flush it but it's not that. Even if I don't use the toilet, the odor is present. Strangely, the toilet doesn't smell when I flush it. Any possible explanation? Thanks!
Unfortunately if sewer gases are backing up through a sink drain, replacing the drain and trap are unlikely to fix the problem. One needs to find the cause such as improper venting that tends to cause water to siphon out of a trap.
I suspect that when you run water, the draining water is displacing sewer gases in the piping that should be vented above the roof but instead are entering the drain system.
(Aug 6, 2014) Paula said:
We had a new lateral line dug because our original two were saturated and now we have a sewer smell in one bathroom daily and once in the whole house. Our plumber crawled under the house and didn't see any leaks. We had just had the tank pumped out and no one can figure it out. Help
If you are sure that the smell problem originated with the excavation and drainfield line work then I'd be looking for an error in the installation that blocked a drainfield line, D-box, etc.
ALso check the obvious and unrelated causes: a loose toilet, bad wax ring seal, improper venting.
9/1/2014 Fiona said:
Can anyone help please. New house, two bathrooms finished, terrible smell from one. Then installed the next en suite and the smell is now in that room and gone from the previous room? We put a new toilet in the old room that smelt and new toilet in the new en suite but used the same cistern. We still have another en suite to complete but the smell in the new one is awful. We have an eco friendly septic tank. Does anyone have any ideas please?
Check for incomplete or improper drain, waste, or vent plumbing for the smelly bathroom
(Oct 26, 2014) septic leaks thru lid of old cement 1000 gallon tank. said:
We have used dirt on top, plastic when lid is reset to try to act as a gasket, but nothing works. Any suggestions?
Watch out: what you describe may be unsafe if the septic tank lid is not properly selected and installed - someone falling into the septic tank usually dies.
Ask your plumber about signs of a backup at the septic tank or about installing a septic tank vent in an appropriate area.
(Dec 4, 2014) David said:
My house is 30+ years old. about 5 years ago sewer gas odor was detected in the daylight basement where there is a floor drain. The drains are all abs plastic, except that when I opened up the concrete floor and exposed the trap, it was cast iron. (presumably because the plastic traps in those days did not have a built in tap for the primer water.) I found out that while an old cast iron trap will hold water molecules, it can deteriate over time and allow gas molecules to pass through the pipe walls. I replaced the trap and the odor disappeared for a couple of years. Unfortunately the problem has returned. By the way, it is only present during cold weather. I recently opened a wall in the smelly area and replaced a couple of vent pipe couplings that were leaking gas, but still have the problem. Just wondering if I am going to have to open all the walls and floors and redo all the drains associated with this area of the house. Half would be under concrete and finished floors, ugh. Also, I found the leaks initially by injecting a detectable gas into the system. Can anyone share a potent gas and very sensitive detector that could be used in the search?
Sure - see the TIF8800 at GAS DETECTION INSTRUMENTS
(Dec 7, 2014) Anonymous said:
I HAVE A GAS ODOR IN MY MAIN FLOOR BATHROOM. HOW DO I GET RID OF THIS ODOR?
Anon the most effective odor cure is to find and fix the odor source. For the case you cite, in More ReDeing links just above,, try the diagnostic suggestions in the article above.
(Jan 14, 2015) Marge H said:
I have two, related issues. Each winter, whenever there is a really cold spell, we smell sewer odors, primarily in the basement. We just bought this house several years ago and noticed several months after the closing, of course, that a white pvc pipe, similar to what comes out of the roof in one of our bathrooms, is open down into the basement. I think this may be the source, but not sure what to do about it. Any suggestions?
(Jan 31, 2015) Anonymous said:
my septic tank vent is locate approx.8 ' from the septic tank and approx 3' higher,on very cold days the vent will backup and waste will flow from the vent,have lived in this home for approx.401 yeaRS AND HAVE ONLY NOTICED THE PROBLEM FOR THE LAST FEW YEARS.HAD THE SEPTIC TANK PUMPED OUT 2 YEARS AGO AND I AM THE ONLY PERSON LIVING IN THE HOME.
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