Stinky dishwasher and washing machine drains

[Bob D]

We have a strong, mostly sulpher smell coming from the kitchen sink-drain, disposal side, most strong when the dishwasher is running.

Also, a similar funky smell from the basement laundry sink when the front loading clothes washer runs. In fact I just checked this out yesterday and it seems to be the wastewater being pumped out of the washer that stinks.

We've tried ice and lemons in the disposal, and vinegar/soda rinses in both the dish and clothes washer. Any ideas?

Bob

[jadnashua]

Do you have any smell from fresh hot water from the tap? Local water conditions can react with the sacrificial anode in a water heater, and produce some smells in hot water. If that's it, the solution is to change the anode to a different type.

But, if it is your drains smelling, not the water going into them, it's more likely that they are not trapped and vented properly and what you're smelling is sewer gasses because the trap siphoned dry. This would likely only happen after the appliance stopped pumping. Both a DW and a WM pump water, rather than gravity doing its thing, so there's more velocity, and that can stress a trap/vent/drain system more than just water flowing under gravity.

If the laundry sink has a long trap arm before the trap (assuming it does have a trap), that long arm can accumulate lots of deposits over the years, and when they get wet, smell pretty nasty. That's one reason why it's best to have the trap directly below, with a short drop to it...less area above the trap that can get dirty, and thus smell.