Would it be possible for gas to build up in a drain and cause a explosive sound like a loud thump? I live in a mobile home park and my home is situated at a point where my home is on the end of the sewer line. Like if you where a house at the end of a road. I have been getting rotten egg smell for years which only can be noticed when I run water down the drain in the kitchen. The kitchen sink is on the opposite end of the home from the sewer hookup.

Your kitchen sink should have a drain vent that allows air to escape when you put water down the drain. Most generally go up and out your roof. If there is some obstruction you could hear noises and have smells and may have to be cleaned-out. If you only smell it by the sink, that's where I'd look first. If you have a dishwasher connected to your sink, it may not be connected properly, or clogged, allowing stinky water to stay in the pipes. Making water flow in the sink can disturb the stinky air in your d.w. drain and make nasty smells too. I'd look at the d.w. first. Hope this helps.

Your kitchen sink should have a drain vent that allows air to escape when you put water down the drain. Most generally go up and out your roof. If there is some obstruction you could hear noises and have smells and may have to be cleaned-out. If you only smell it by the sink, that's where I'd look first. If you have a dishwasher connected to your sink, it may not be connected properly, or clogged, allowing stinky water to stay in the pipes. Making water flow in the sink can disturb the stinky air in your d.w. drain and make nasty smells too. I'd look at the d.w. first. Hope this helps.

Reply:
Actually the smell is down near the bathroom which is about 40 feet away from the drain for the kitchen. Also not sure but there is a drain near the bathroom which is for the washer and I think that connects to the line from the kitchen which somehow connects to where the toilet is. The vents and drain are clear but not sure if any water remains in that drain from the kitchen. I am just trying to eliminate the source of this noise I hear every now and then. Somewhere along the area of that drain from the kitchen this noise like a large tree fell on the roof happens. Really strange because of how loud it is.

Do you have a private sewer (septic tank?)

Please clarify. You have an odor in the bathroom, but only when you run water the kitchen sink. Is that correct? You hear a loud noise when you run water at the kitchen sink. Do you hear that noise when the water is running or do you hear it when you turn the water off? Do you hear the noise when you use water at any other place?

Stop up the kitchen sink, fill the sink with water. Turn off the water. Did you hear the noise when you closed the kitchen faucet? Remove the drain stopper and run to the bathroom. Do you smell the odor? If you smell the odor, sniff around the base of the toilet. Is the odor stronger there?

Please clarify. You have an odor in the bathroom, but only when you run water the kitchen sink. Is that correct? You hear a loud noise when you run water at the kitchen sink. Do you hear that noise when the water is running or do you hear it when you turn the water off? Do you hear the noise when you use water at any other place?

Stop up the kitchen sink, fill the sink with water. Turn off the water. Did you hear the noise when you closed the kitchen faucet? Remove the drain stopper and run to the bathroom. Do you smell the odor? If you smell the odor, sniff around the base of the toilet. Is the odor stronger there?

Reply:
To note the running water has nothing to do with the noise , the rotten egg smell is noticed in the hall outside the bathroom when you run the water in the kitchen sink. The noise is like if you were to lift the end of a couch several feet up and drop it. It seems to be from the area of the drain pipe between the kitchen and bathroom. It also sounds like the noise that is made when you put air in a paper bag and pop it only much louder.

Did you do as requested?