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I bought a house and part of the condition of sale was that the pipe heading out of my house to the city sewer was to be replaced as it was showing damage. Shortly after moving in I had a pretty significant blockage that required a call to a plumber to snake it. While there he sent down a probe to take a look and also probed the pipe’s elevation.
Between my house and the city sewer is about 70 feet. The difference in elevation between my house and the point where the pipe met the city sewer is 7 inches. That is, the pipe leaving my house is 7 inches lower than where it meets the city sewer.
So I’m not a plumber or anything but water is supposed to flow uphill right?