Water smell, but only in last sink in the house

[Hardyh]

I am working on sorting out an issue with our well water but google searches aren't coming up with this particular situation. Our well water, which is hard water (no iron stains, etc but eventual mineral buildup on the faucet screens), has a certain smell to it - but it is really only noticeable from one sink it the house. Our second bathroom sink can get quite smelly, when looking up the smell description it doesn't smell like rotten eggs exactly but maybe sulfur-ish? It is a deep well (250ft) that was installed about 5 years ago - the smell has been there since and we didn't have it from the shallow well that we used to depend on.
In the mean time I have replaced the sink and p-trap but that didn't change anything. It seems to build up, if I let the water run it becomes less noticeable and it also seems like it's primarily from the cold water.
This sink is located the furthest away from the water inlet/pressure tank, that is every other water faucet is closer to the inlet than this sink.Technically the shower next to it is a little further (because it is higher up) but I don't get the same smell from that. It is also located upstairs while the inlet/pressure tank is in the basement.
My question is; is it possible that it is some kind of gas (like H2S) that just so happens to all build up at the end of the line? Is there anything that can be done to this particular faucet/water line that would reduce the smell - like an air eliminator/purger a bit past the sink line?

 

[WorthFlorida]

Cold water only, hot water only, or both? The sink with this issue, it's the furthest, is it also the highest fixture In the home? Is it continuous or just when the water is turned on? With a handful of water, does the water itself smell? Taste Ok?

 

[Sponsor]

 

[Hardyh]

Cold water only, hot water only, or both?

It seems like primarily cold water, when I run the hot it smells a bit but seems to subside faster.

is it also the highest fixture In the home?

The shower head next to it is the only higher fixture but I don't notice the same smell with the shower on.

Is it continuous or just when the water is turned on?

The fixture doesn't smell until the water in turned on.

With a handful of water, does the water itself smell?

No, it smells pretty normal.

Taste Ok?

Yes, it doesn't taste weird.

 

[WorthFlorida]

Continuous, I meant as the water is running. All is OK when the water is turned off? The shower/tub valve maybe a few inches lower than the sink? No issues when the toilet is flushed?

 

[Hardyh]

It dissipates after a while when the water is running, it is definitely strongest right after opening the tap. No issues from the toilet, nor smell from the toilet water. The shower (it's a walk in) valve is a few inches higher than the sink, but I just turned it on and it doesn't have the same smell.

 

[WorthFlorida]

I was hoping others would reply. Odors from water can be tough to resolve. Since it seems to be this one sink issue and not the faucet causing it, I would look into getting a carbon water filter installed in the cold side. Under the sink filter are not very expensive. This is a simple one, filters are usua sold at any hardware store. There were other brands that sold nearly the same housing. This one has 3/8" connections that is standard for sink faucets.

Hydroviv | Under Sink Filter | Featured On Shark Tank

This under sink water filtration system removes lead, PFAS, VOCs, chromium-6, mercury and much more from your water. Purchase this custom water filter online here.

www.hydroviv.com

 

[Hardyh]

Thank you, that was kind of the direction I was thinking of starting with. Would under the counter make more sense than right after the pressure tank so it filters everything? I came across aeration solutions as well, but they all look quite pricey. I have a spare circulation pump, would a return loop to keep the water moving do anything?

 

[LLigetfa]

Try removing the supply lines after the angle stops and clean them well with a strong bleach solution. Blow (or suck) some string through the line, tie some cloth on the end of it and pull it through. My guess is bacteria in the supply line.

 

[John Gayewski]

Are you sure it's the water that smells? It generally isn't the water, but sewer gas or dirty tailpiece. Or stinky pop up. The water is just stirring up the smell.

 

[Hardyh]

Are you sure it's the water that smells? It generally isn't the water, but sewer gas or dirty tailpiece. Or stinky pop up. The water is just stirring up the smell.

Initially I thought it was the drain/sink/overflow so I replaced the sink and the p-trap. The smell just started when we switched from our shallow well to a new deep well.

 

[Hardyh]

Try removing the supply lines after the angle stops and clean them well with a strong bleach solution. Blow (or suck) some string through the line, tie some cloth on the end of it and pull it through. My guess is bacteria in the supply line.

Ok, I will try that too thank you. Would older pipes potentially cause the same thing? The house is plumbed with poly b, probably 20-30 years old.

 

[Reach4]

You might consider sanitizing your new well and your whole plumbing system.

If you wanted to sanitize a segment of some piping, you might be able to use a small pump to circulate a solution, but really new wells should be sanitized anyway. Nice project for warmer weather.

 

[Hardyh]

You might consider sanitizing your new well and your whole plumbing system.

If you wanted to sanitize a segment of some piping, you might be able to use a small pump to circulate a solution, but really new wells should be sanitized anyway. Nice project for warmer weather.

The well is 4 or 5 years old now, I tried sanitizing based on something like this guide about a year after the well was drilled when I first tried to figure out the smell issue. I think the process did have a short term effect but the smell was back within a month or less, I have repeated the sanitizing process a couple of times since then. We actually find that the smell, although always there to a degree, does go away a bit and then becomes stronger at other times - the last few weeks have been really noticeable which is why I have a renewed interest in fixing this.
I think that changing out the old poly-b to pex on the back run of the house might be a next step - everything is easily accessible from the unfinished basement. It's just weird how the smell is concentrated in the last tap in the house.

 

[John Gayewski]

Initially I thought it was the drain/sink/overflow so I replaced the sink and the p-trap. The smell just started when we switched from our shallow well to a new deep well.

You said you could only smell it at one sink. What does the well have to do with anything?

 

[Hardyh]

You said you could only smell it at one sink. What does the well have to do with anything?

We didn't have any smells when we were on the shallow well, it didn't start until we switched to the new one. I'm not sure it has anything to do with it but I thought it might be relevant.

 

[John Gayewski]

If the water only smells at one sink then the problem is local to that sink.

You should collect some of the water and bring it out of the room, then smell it. See if it's actually the water. You could then even have the sample tested to see what's in it.

 

[Jeff H Young]

process of elimination. You have to be absolutely sure of one thing at a time. So.... No reason to worry about sink overflow if you are 100 % sure its water .
Drop some coin on a h2s tester from Amazon , or Ask around fire department health department , building safety or something? but it seems for 80 bucks youll at least know yes its h2s or no it is not.

 

[Hardyh]

I'm going to check the drain/overflow again as well as the supply lines - I can't seem to smell anything if I put some water into a glass and smell it. I'm not 100% sure it is the water after all, I just thought that dealing with the sink once would have removed that as a source.

 

[Reach4]

The well is 4 or 5 years old now, I tried sanitizing based on something like this guide about a year after the well was drilled when I first tried to figure out the smell issue. I think the process did have a short term effect but the smell was back within a month or less, I have repeated the sanitizing process a couple of times since then.

My write-up is a lot more intense. One area of difference that come to mind is that I address the space below the pump and the area just outside of the well. Another is that your site computes the amount of bleach needed, but bleach gets consumed doing its job. Yet if you can smell the chlorine at each tap, then the bleach has not been consumed at that point.

There are other differences, and one in which my write-up suffers is that it is not succinct.

Well sanitizing (extra attention to 4 inch casing)

My favorite well sanitizing procedure that I have seen is http://www.moravecwaterwells.com/disinfection However I have some added thoughts that point to needing larger flooding volume (F.V), more bleach than predicted, and more vinegar than predicted maybe. During the process, you recirculate...

terrylove.com

Note that the reason I mention 4-inch casing is that prevents the use of special sanitizing pellets that sink to the bottom. I mention top feeding for the same reason... you can drive liquid chlorinated water to the bottom of a bottom-feeding well, but you cannot do that for a top-feeding well. You do what you can.

 

[Hardyh]

Thanks, I will try that again - I do remember backwashing as we installed a hydrant right by the well and I cycled it for quite a while before sending the chlorine through the rest of the system. I didn't do the vinegar though.