We have a kitchen sink w/ a divider in the middle (2 sinks). Often when I turn on the garbage disposal, food particles will come up through the drain in the other side of the sink.
Today this occurred, but all the water came up as well and now neither side of the sink will drain. Any ideas?

Thanks!

You have a blockage in the horizontal line in the wall. Remove the "J" bend of the trap and send a snake up into the wall. You will hit a bend about 8 inches in but work around it and you only have 5 more feet to go. Flush the line out with hot water afterwards. Good luck, Tom