I recently moved out of my old apartment two weeks before my lease ended. I went back a couple days before the lease ended to do a final cleaning to insure I'd get my security deposit back. I walked into a double kitchen sink overflowing with waste water. I could not reach the landlord that day and didn't want to just leave the problem, so I pulled the pvc under the sink and let the waste water drain into a bucket, the flushed it, and reattached the pvc. Two days later I returned to talk to the and lord and the sink was overflowing again with waste water, this time worse than before. Inches of waste water was standing on the kitchen floor. Now the landlord is saying that the waste water was caused my a grease blockage in OUR drain. Does this sound right? There are a total of 6 apartments in this building. If there was a blockage in our drain wouldn't that prevent water from both draining and also coming up the wrong way? If there was a blockage past our drain pipes couldn't that have been caused by any of the units? It's a 3 story building with 2 units on each floor. Ours was one on the ground level

What you have coming up out of your sink is the drainage from the upper units. Since the drainage is all connected together this should make it a common area problem. You cannot be blamed for this and the cost of repair should be picked up by the landlord. Let me know how you make out. Good luck, Tom