Help on sulfur smell

So this is a new one on me. New neighbor called and said he is getting a sulfur smell from the COLD water faucet in a single bathroom. Not hot and no other faucets.

This is new construction and new well, maybe 6 months old. All equipment and plumbing lines are new. PEX distribution and has two full house filters. One is a sediment filter and one is an activated charcoal filter. This is faucet closest to the filters.

It has me stumped. Any ideas?

Well Water…
Hydrogen Sulfide.
(a rotten egg odor)
They need to contact a well treatment contractor.

I would have thought so as well but it is limited to a single cold water faucet. The kitchen faucet and ice maker, as well as the other 3 bathrooms and exterior faucets are all ok. Thanks Joe.

By any chance is this fixture by passing the filter?

Change the faucet , if it is not used much may have bacteria in it

System probably needs a chlorinator.

If is is only one faucet , I would start there . keep it simple

I would disinfect the entire system just to be sure.

Disinfecting Your Well
This procedure is designed for the typical four-inch (4”) diameter well with a submersible pump.
Your well may be different. If so, you may need to contact a professional to disinfect the

  1. Shut off power to pump and water heater. Drain water from the pressure tank, water
    heater, and all water lines (including indoor water lines at faucets). Consult with the
    water treatment or filtration system manufacturer for any additional or special
  2. Obtain one of the following:
    One (1) gallon of unscented household bleach (5-6% sodium hypochlorite).
    Half (½) gallon of liquid pool chlorine (10% sodium hypochlorite).
    The bigger your water distribution system, the more chlorine solution you will
    need for effective disinfection.
  3. Add the bleach/pool chlorine to four to five (4-5) gallons of water in a well ventilate area.
    You can use the same well water that you are disinfecting.
  4. Remove one-half inch (1/2") access plug from top of casing (see diagram above) and
    pour chlorine solution into well through opening. Follow with two gallons of plain water.
    Replace plug.
  5. Turn power on, start pump, and fill the pressure tank. Open all faucets, one at a time,
    until bleach odor of the chlorine is recognized, then close spigots.
  6. Do not use any water from the system for 10 to 12 hours - water will have a high
    concentration of chlorine and may irritate sensitive tissues. Allow power to remain on to
    maintain pressure in tank.
  7. After 10 to 12 hours, thoroughly drain and flush both tanks (hot water and pressure) and
    all lines (including shower heads); allowing water to run from faucets until no odor of
    chlorine bleach is present. Flush outside lines first. If you don’t detect a chlorine odor
    upon flushing, re-disinfect the well. Please note that chlorine may also harm plants and

Sample the water.
Start with water sampling before removing and replacing mechanical fixtures
The composition and analysis of the well will give you a baseline start.

Shocking a well land system can actually be a bit more basic.

1 gallon of chlorine for every 300 ft of well casing. Remove the well head, pour in the bleach. Pull into the system in the home until you smell it at all water sources. Leave it for 12 hours. Flush at the outside faucets only… if you have a septic system to avoid effecting the septic organics and balance. Flush the other areas (bathrooms, kitchen, etc) briefly just to clear the lines. That will sanitize your system. Do the process 2 times per year. You shouldn’t have to empty tanks in this scenario. The rule of thumb with the chlorine, a little more is better.

Good one Roy thanks. :slight_smile: