[titusclan]

I have a dual kitchen sink with a garbage disposal (non-working) on the right side. Underneath, the drain pipe for the garbage disposal connects to the pipe for the left side and then goes down. There is also a reverse-osmosis drinking faucet thing attached under there somewhere.
Earlier today, the left sink started draining very slowly. The right side would drain a little quicker (if I put the water from the left sink into the right sink it would drain quicker than if I left it on the right side). Later in the day, water started backing up into the left side of the sink. We've tried pouring in drano/liquid plumber but water is still filling up the left side (from the bottom up). If I try stopping up the sink/sinks, the water will come out of the pipes underneath.
Help please

[speedball1]

the right side. Underneath, the drain pipe for the garbage disposal connects to the pipe for the left side and then goes down.

It doesn't go into the wall and vents out the roof? Down to what?

the left sink started draining very slowly. The right side would drain a little quicker (if I put the water from the left sink into the right sink it would drain quicker than if I left it on the right side). Later in the day, water started backing up into the left side of the sink.

You have a blockage in the drain line. Remove the "J" bend from the trap and snake the drain from there. Good luck, Tom

[afaroo]

Hello Titusclan,

I agree with Tom, you have a blockage in the drian, remove the "J" bend and snake it see the images below, Thanks.

John