Lately when I flush my toilet the water in the bowl fills up to the rim, but not every time. I remove most of the water from bowl and plunge. It took 3 times a few weeks ago to get a normnal flush. There was a "wooshing" sound and the water went down. Now its doing it again. I have city sewer. The plumber is coming tomorrow. Any ideas on what is going on? There are no kids in the house to flush a toy, etc.
thanks