an apparatus and method for improving the operation of sewer systems includes a first sewer pipe connected to a source of other water and a second smaller diameter sewer pipe passing through the first sewer pipe and connected to sources of sanitary effluent . the second sewer pipe can be attached to the interior surfaces of the first sewer line by a curable adhesive material using a removable inflatable bladder to hold the second sewer pipe in position until the adhesive has cured sufficiently . as an alternative , positioning walls or arms , integral with the second pipe , form positioning spaces filled with a slurry material to hold the second sewer pipe in position . the slurry will harden in place to form an integral unit with the second pipe and the positioning walls or arms .