I own an older farmhouse (100+ years old) and under certian conditions like when there is a strong west wind there is a sewage type odor that seems to be emiting from the crawlspace that permeates the house. The system is on a septic system that is only 3 years old, I had the system pumped out two months ago. I have inspected the plumbing system in the crawlspace looking for cracked or damaged pipes, I did repair "bad" pipe and capped an open "T", I have looked for open pipes or abandoned old sewer lines. The vent on the roof is clear. I have had a number of contractors look at this and I have not had any luck. Any suggestions???

Septic odors can come from a host of issues. Some if which you aready addressed. When you say that the odor is coming from the west. Is that where the septic tank is located in relationship to the house? You may need to cap the pipe where it enters the septic tank then fill the drain pipes with water to see if there is another leak that you did not find. Do you have a gray water system? Is the gray water system coming up to daylight any place? What about neighbors. Is their sytem close to your home? Perhaps the odor is coming from that?

Thanks for the reply, the septic tank is located to the west of the house as is the septic field. The odor is only noticed when there is a strong west wind, the odor does not appear to be outdoors just in the crawlspace. We don't have a gray water system and my closest neighbor is a few hundred yards away. I will keep looking for more missed bad pipes, filling the system and looking for leaks might be an option.

Found one more bad pipe, top was rusted through and was venting into the house. Pipe has been repaired and the odor appears to have been eliminated.

Thanks for the feedback