We have a strange situation where the water in one of our master bathroom faucets has a strong odor, briefly, that smells like a sewer. There are 2 sinks and it only happens with one of them. It only happens when cold water is running, whether alone or mixed with hot. The odor is very strong and lasts only about a minute. Water drains well in the sink with the odor, no slow drain problems.

This has been happening for a month, so we only use the other sink while we tried to figure this out. There is no odor from the water from that sink's faucet nor from any other faucet in the house.

Here is what we have tried/done: We are on a water well. We have tried putting bleach down the drain and the overflow. We have tried using Liquid Plumber down the drain and overflow. No success. We plugged the overflow with a tissue and turned the cold water on and smelled it, so it is not something nasty growing in the overflow. We have tried plunging the sink and nothing comes up. We completely remodeled this bathroom 1 1/2 years ago so the sink is pretty new. All the plumbling going to the sinks was replaced.

Please help us solve this mystery.

BTW, this is a Delta faucet.

There are some great plumbers on this site so I am sure you will get some answers. For me I am going to say that there is a vent issue at the sink. It is common for people to blame the water in these situations but if you pour some in a pitcher and take it out of the room and smell it I am betting there is no problem there. Of coarse you would want to make sure the trap under the sink is in place and done right (with no leaks!) The vent I am referring to would be in the wall and would normally extend to the outside via roof vent. The fact that you remodeled actually makes me more suspicious since many things can happen during that process to create a vent problem. If sewer gas is accumulating and getting trapped at this location it can sneak out in tiny amounts during the drain process. I am eager to see what the others think about this. Good luck

Hi guys!

My first thought when reading your post, jsccastlerock was the vent being a problem like Mfrench suggested... very likely in most complaints like this... ;)

Mfrench presented a good idea when he said to fill a pitcher full of cold water, leave the room and smell it. I'd like you to try that and then post back with the result as well as the answers to the following questions, OK?

1) Look up under the sink that has the issue and see if the water supply tube going to the cold water of the faucet is different than the water supply tube going to the hot water of the faucet. If the supply tube is different, look up under the other sink (sink with no issue) and compare tubes there, too. Report back on findings...

2) Measuring from the center of sink one, how far is it over to the center of sink two?

3) Do these sinks share a common Ptrap (is there only one Ptrap for both sinks)?

4) By chance is there a mechanical vent under this sink (far-fetched, but check). This mechanical vent would be above the PTRAP and usually threads into the pipe (can be removed)?

5) Finally, what material is the cold water piping made from... is it different than the hot water supply?

Back to you...

Mark

I have the same issue in my master bath and 2nd bath. And it only occurs in the left sink of both double sink arrangements. Like the original poster, I poured vinegar & baking soda, bleach, Liquid Plumber, etc. down the drains and vent in the sink. I have taken cold water samples out of each room and still notice the odor so in my opinion, it is the water. We are on a well and chlorinate yearly.

Six months ago I called Price Pfister and they replaced the hoses as this was a recent remodel as well. The odor came back.

I am so frustrated (and grossed out by the smell)!

Please help?