Smelling sewer in lower level & outside
Recently I started smelling a sewage smell in the lower level where the laundry and bathroom are. I first noticed the smell last week coming from the pipe that the washer drains into. Now it's worse and the whole bathroom next to it smells. I can't pinpoint the smell in the bathroom. It's down low near the floor. I don't smell it in the sink or shower drain. Outside the smell is down low against that side of the house. I don't smell it where the drain field is.
It's been very windy and cold here, in the teens this week. The smell got worse when the weather got colder. The toilets are flushing fine and the sinks are draining as normal. No signs of backup that I can tell, except for the smell.
The septic was pumped and inspected this past July when I bought the house. I only noticed the smell when it got cold and windy. People have told me it's just sewage gas from the stack vent, but I'm worried it's a worse problem.