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Plumbing in the Home/basement floor drain sewer smell


We have a terrible odor that started in the basement on Saturday and by Sunday the main floor also stinks.  I thought the smell was mold and called an environmental mold guy to come find/test.  He didn't find mold and said it was a sewer gas smell.  Trying to find what to do, points to a plumber.  I did call our sewer department and they claim if smell is in house that it is internal problem and to pour a lot of water into drain.  I tried that yesterday and it still smells.  How long should it take before smell is gone if it is a dry drain.  Also, I can see water in the drain anyway, so I would not think it could be dry.  So who do I call for help and could I use a hand auger to check for blockage?  We have had sewer back up twice about a year apart, but the last time was several months ago.

Dear Kay,

   Odor problems can be very difficult to track down.  As long as there is water in the trap of the drain, then sewer gas is prevented from entering through the trap under normal circumstances.  A dry trap would allow the odor from the gases to pass through the pipe into the house, but it should clear up very quickly once the trap is filled.

   It is possible that gas could be coming in from another source, such as another trap which has become dry.... these gases can be heavier than air and stay close to the ground which would give the impression that it was coming from the floor drain when it could be a tub, shower, sink or toilet.  It could also be any other type of opening in the pipe such as a cleanout or even a break in the line beneath the floor.

   I know this hasn't narrowed things down much for you, but I hope that the information can help you find the source and fix it.

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Thomas Ambler


I am experienced at troubleshooting and solving all types of plumbing problems. Issues related to specific manufacturers fixtures and specifications though are beyond my field of expertise. I have dealt with problems in both rural and urban areas, and with water supply and drainage systems. Plumbing issues can be very obscure... such as odors, stains or occasional seepage. I have even had to chase rats from a customer's sewer line.


I have 25 years experience dealing with plumbing systems (which also includes hot water and steam heating systems). My main expertise is in diagnosing and solving problems. I have worked in construction and installation of new systems but do not regard myself as an expert in that area.

Asbury Park Press, Seattle Times, Denver Post.

I completed high school and one year of college. I served 4 years in the Marine Corps and have education in electronic and electrical troubleshooting and repair. I have attended classes on installing and repair of oil burners, and I have EPA universal certification for air conditioning and refrigeration. I am now enrolled as a full-time student at Everest college to re-train for a new career. Any donations of financial support would be greatly appreciated.

Past/Present Clients
All of Denny's Restaurants in NJ, Several Burger King stores, I have done work at two different homes for Bruce Springsteen. I have also worked for Jim Johnson (of J&J) and his family, Whitney Houston, Steve Forbes and many others.

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