Why is my laundry standpipe overflowing from kitchen sink activity?

Question

My kitchen is next to my laundry room. Whenever my kitchen faucet (double bowl style) doesn’t drain water, I run the disposal and I see water filling on the second bowl (the one without the disposal). As water goes down in both bowls, water and food particles start coming out of the water stand pipe in the laundry room.

Answer 1

Your drain pipe is blocked somewhere past the point where the sink and laundry drains join together. The disposal is forcing water against the blockage and so it's being pushed up the laundry standpipe.

The first thing to do is something you can do yourself, and is the first thing a plumber would do anyway. Remove the trap below the sink and snake out the drain from there as best you can.

1. Buy a manual drain auger like this one. It's a random example of a cheap one. It's useful and will save you lots of money on plumbers. 25 feet is a good length. Most blockages are in the first 10 feet.
2. Remove the trap below the sink and snake out the drain from there. Watch videos like this one to learn how. Search for more videos like "sink trap auger".
3. If the blockage is buildup of grease from the kitchen sink, you won't remove all of it with a cheap auger like that, but you should get enough that the sink doesn't back up and the disposal doesn't shoot food out the laundry. You can then follow up with a whole bottle of mainline cleaner. But don't use chemicals like that til you've cleared it a little.

• Note, after using the auger, wipe it down, unravel it fully and lay it out to dry, then wipe it with a layer of oil before coiling it back up. This will reduce rusting a lot.

Follow up to avoid having this happen again:

• Don't use the disposal as a garbage can. Put most of your food garbage in the garbage, and use the disposal only to catch the smaller bits that you rinse off dishes or scrape off pots.
• Especially don't pour cooking oil, oil from frying, or oily things like peanut butter etc down the disposal. Scrape those thoroughly into the garbage.
• These tips are especially important if your grease-blocked pipes are then going to receive gobs of lint from the washing machine. You can't help that, so help it by not having grease-blocked pipes.