Living short term in Riverside in a very nice unit however there is a horrible stench coming from the toilet. I believe that sewage gas is seeping into our bathroom via the toilet. The smell is absolutely horrible at times. Other times I can smell a mixture of sewage and laundery water (we don't have a washing machine.)At first I thought maybe it was coming from the plumbing closet in the bathroom but when I open it all I smell is a musty odor.It is unbearable at times, anybody else have this problem?

What floor do you live on? Bathroom window open?

Difficult for sewage gas to come in via the toilet unless the toilet has been installed incorrectly, it would have to come in through the pipe but there is or should be a water trap in the toilet,

In Thai construction there are often drains in the bathroom floors. These are the source of gas coming in from septic/waste tanks because they are not trapped installations. There is a very small often ineffective trap in the top of the drain but it must be filled with water all the time to have a chance of being effective.

What floor do you live on? Bathroom window open?

Difficult for sewage gas to come in via the toilet unless the toilet has been installed incorrectly, it would have to come in through the pipe but there is or should be a water trap in the toilet,

In Thai construction there are often drains in the bathroom floors. These are the source of gas coming in from septic/waste tanks because they are not trapped installations. There is a very small often ineffective trap in the top of the drain but it must be filled with water all the time to have a chance of being effective.

Brilliant! You are correct, there is a drain behind the toilet that I didn't notice. I could see down into it about 6 inches until it bent and there wasn't any water in it. I filled it with water and put my plunger on top of it. Hopefully that will put an end to it. Thanks for your help!

de nada

by covering the drain you will learn if it is the source of the problem

those little drain traps dry out fast and sometimes the cup attached under the drain grate is damaged or missing making the trap ineffective

good luck

Inform the manager,caretaker,handyman. And let them deal with it.

Yes, if traps become dry, there can be a sewage odor. Is anyone using the toilet sprayer to flush the toilet? That, also, can eliminate the water from the toilet trap, creating an odor.

Difficult for sewage gas to come in via the toilet unless the toilet has been installed incorrectly.......There is a very small often ineffective trap in the top of the drain but it must be filled with water all the time to have a chance of being effective.

I once had the smell and water seeping out from under the toilet. Turned out that the toilet was simply placed over the hole with no beeswax (moldable) seal, so if there was a back up and the grouting around the toilet dried and cracked, sewage seeped out.

Once that was fixed, then the only odors I have ever gotten have come from floor drain, as Dante99 pointed out.