Sewer Line Leaks & Odors

This article describes how to diagnose, find, and cure odors in buildings including septic or sewage or sewer gas smells or "gas odors" in buildings.

- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

Septic System or Sewer Piping Blockage or Failure Can Produce Sewer or Septic Gases Outdoors OR Indoors

Our sewer gas odor diagnosis discussed here focuses 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.

Readers should be sure to also

Watch Out : Because sewer gas contains methane gas (CH 4 ) there is a risk of an explosion hazard or even fatal asphyxiation.

Sewer gases also probably contain hydrogen sulfide gas (H 2 S) 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.

Sewer gas odors that can occur when a drain or septic system are partly blocked or sluggish.

Inspect the septic system for evidence of failure : our photo shows green septic dye in the yard during a septic loading and dye test.

If the sewer or gas odor or smell is strongest outside, and if you rule out an unusual site shape or wind blowing odors down from your plumbing vent system, your septic system may be failing.

Sewage odors may be noticed from a failing drainfield even if at the moment you don't see a wet or soggy area which shows actual sewage effluent on the yard surface.

If this is the case you may want to request a septic system inspection as well as a tank pumpout and inspection afterwards.

Also see SEWER GAS ODORS in COLD / WET WEATHER for additional odor tracing and cure advice for odors occurring during wet or cold weather.

Check for a sewer line vent through the building foundation wall :

I often find that a vent has been placed at a house foundation wall just above where the sewer line leaves the building. I suspect the plumber thought that this would aid drainage into the septic tank.

Reply:

Because of the significant variation in the rate, density, concentration and composition of sewer gas that might be leaking into a building, concentration is not measured by the typical investigator. Rather she uses a broad-spectrum combustible gas detection instrument such as the TIF8800 discussed in these pages

- with the caveat that that sort of instrument will respond to a wide range of combustible gases. It's the use of the tool in proper context that makes it a reliable and appropriate method.

If for technical reasons you needed to know the concentration of sewer gases, or perhaps of just methane - a primary component - there are more costly and sophisticated electronic instruments that can do that.

• The BW HONEYWELL GASALERT MICROCLIP XL 4-GAS MONITOR MCXL-XWHM-Y-NA - is about $500.
• the RKI INSTRUMENTS MULTI-GAS DETECTOR GX-2012 - is about $1000.

Similarly, some natural gas service companies use a quantitative measurement rather than mere detection.

Sewer Gas Detection Research

• Barsky, J. B., SS Que Hee, and C. S. Clark. "An evaluation of the response of some portable, direct-reading 10.2 eV and 11.8 eV photoionization detectors, and a flame ionization gas chromatograph for organic vapors in high humidity atmospheres." The American Industrial Hygiene Association Journal 46, no. 1 (1985): 9-14.
• Beardsley, C. W., N. J. Krotinger, and J. H. Rigdon. "Removal of sewer odors by scrubbing with alkaline solutions." Sewage and Industrial Wastes (1958): 220-225.
• Dincer, Faruk, and Aysen Muezzinoglu. "Odor determination at wastewater collection systems: Olfactometry versus H2S analyses." CLEAN–Soil, Air, Water 35, no. 6 (2007): 565-570.
• Fan, Chi-Yuan, Richard Field, William C. Pisano, James Barsanti, James J. Joyce, and Harvey Sorenson. "Sewer and tank flushing for sediment, corrosion, and pollution control." Journal of Water Resources Planning and Management 127, no. 3 (2001): 194-201.
• Frechen, Franz-Bernd, and Wulf Köster. "Odour emission capacity of wastewaters—standardization of measurement method and application." Water Science and technology 38, no. 3 (1998): 61-69.
• Guisasola, Albert, David de Haas, Jurg Keller, and Zhiguo Yuan. "Methane formation in sewer systems." Water Research 42, no. 6 (2008): 1421-1430.
• Hurwitz, L. J., and GwenethI Taylor. "POISONING BY SEWER GAS: WITH UNUSUAL SEQUEL." The Lancet 263, no. 6822 (1954): 1110-1112.
• Kim, Jihyoung, Jung Soo Lim, Jonathan Friedman, Uichin Lee, Luiz Vieira, Diego Rosso, Mario Gerla, and Mani B. Srivastava. "SewerSnort: A drifting sensor for in-situ sewer gas monitoring." In Sensor, Mesh and Ad Hoc Communications and Networks, 2009. SECON'09. 6th Annual IEEE Communications Society Conference on, pp. 1-9. IEEE, 2009.
• Koo, Dae-Hyun, and Samuel T. Ariaratnam. "Innovative method for assessment of underground sewer pipe condition." Automation in Construction 15, no. 4 (2006): 479-488.
• LUO, Yong, Xiao-bo MAO, and Jun-jie HUANG. "Development of Infrared Methane Sensor." Instrument Technique and Sensor 8 (2007): 001.
• Marrin, Donn L. "Soil‐Gas Sampling and Misinterpretation." Groundwater Monitoring & Remediation 8, no. 2 (1988): 51-54.
• Pandey, Sudhir Kumar, Ki-Hyun Kim, and Kea-Tiong Tang. "A review of sensor-based methods for monitoring hydrogen sulfide." TrAC Trends in Analytical Chemistry 32 (2012): 87-99.
• Stuart, R. D. "Weil's disease in Glasgow sewer workers." British medical journal 1, no. 4076 (1939): 324.
• Watt, Monika M., Stephen J. Watt, and Anthony Seaton. "Episode of toxic gas exposure in sewer workers." Occupational and environmental medicine 54, no. 4 (1997): 277-280
• YANG, Jing, Wei-zhen LIANG, and Qing-qiang MENG. "Monitoring Method for the Combustible and Poisonous Gas from Urban Sewer [J]." China Water & Wastewater 1 (2005): 026.

Recommended Articles

BACKDRAFTING & SEWER/SEPTIC ODORS

CLOGGED DRAIN DIAGNOSIS & REPAIR

DRAIN NOISE DIAGNOSIS

DRAIN PIPING & SEWER ODORS

GAS DETECTION INSTRUMENTS

METHANE & SEWER GAS HAZARDS

ODORS GASES SMELLS, DIAGNOSIS & CURE - home

PLUMBING FIXTURE TRAPS

PLUMBING VENT DEFECTS & NOISES

FORENSIC INVESTIGATION of BUILDINGS

SEPTIC & CESSPOOL SAFEY

SEPTIC SYSTEM ODORS

SEPTIC METHANE GAS

SEWAGE & SEPTIC CONTAMINANTS

SEWAGE CONTAMINATION in BUILDING

SEWAGE EJECTOR / GRINDER PUMPS

SEWAGE PATHOGENS in SEPTIC SLUDGE

SEWAGE BACKUP, WHAT TO DO

SEWAGE BACKUP TEST & CLEANUP

SEWER GAS ODORS - home

SEWER GAS ODORS in COLD / WET WEATHER

SEWER GAS ODOR REMEDIES

SEWER LINE REPLACEMENT

SULPHUR & SEWER GAS SMELL SOURCES

TEST FOR INDOOR SEWER GAS

TIF 8800 GAS DETECTOR

Suggested citation for this web page

TEST FOR INDOOR SEWER GAS at Inspect A pedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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Hard-to-Find Sewer Gas Odor Source FAQs

How to find mysterious sewer or septic smells when the source is not obvious. This article suggests things to check when you have had trouble finding the source of a sewer gas, septic gas, or methane smell in or near a building.

Sometimes the odor source is elusive because it comes and goes, is weather dependent, fixture use dependent, or because the leak is in a building wall or ceiling cavity.

Start with the inexpensive and easy things like checking for dry or defective fixture traps (or fake traps as shown in our page top photo).

- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?

Tips for Tracking Down Hard-to-Find Sewer Gas Odors in buildings

These questions and answers about finding unexpected sources of sewage, septic, or sulphur odors in buildings were posted originally

at SEWAGE ODOR SOURCE LOCATION - please be sure to review that article.

On 2018-11-04 by (mod) - batteries can be a sourece of sulphur-like or sewer-like odors

Thank you very much for this helpful field report of another possible source of sulphur odors ("sewer gas odors") that we had not previously noted: a failing battery such as often found on battery-operated sump pumps and other battery backup systems.

I'll be sure to add your example to our list of unexpected sewer odor sources found at SEWAGE ODOR SOURCE LOCATION.

On 2018-11-04 by Anonymous

I had a plumber come to my basement because of a smell of sulfer (rotten eggs) in the basement. It was getting stronger. We tried looking at all the sewar lines, boiller, etc. He found the smell. It was the the emergency battery on our sump pump.

Either the battery was bad, or the charger was overcharging the battery. Once we removed the battery, the smell disappeared.

On 2018-10-04 by (mod) - venting system problems can cause sewer odors

That sounds to me as if there is a problem with the venting system for the bathroom drain or its fixtures. Ask your plumber to review the details and connections of how the fixtures and drains are vented.

On 2018-10-03 by Amy miano

Hello, I had my bathroom updated about a year ago. Soon after there was a sewer smell that radiates up out of the sink drain and intensifies greatly when the water is turned on and the gas is displaced upward.