To locate a sewage pipe, identify the area where the sewage pipe exits the home, and begin digging at the exit point to follow the pipe through the property. Homeowners can also contact local authorities to obtain maps of the sewage lines on the property.
Find the area where the sewage pipe exits the home, and use a wooden probe to test the area around the pipe's exit point. Sewage pipes typically exit the home through the basement or crawlspace. After hitting a solid object with the probe, dig a small hole that is 12 to 24 inches deep, and examine the hole for the sewage pipe. The sewage pipe typically follows the shortest path from the home to the city disposal system or septic tank.
Local authorities, such as zoning authorities, may have copies of the property map on file. To obtain a map that includes the sewage lines, contact the building or zoning department in the local area. While sewage lines typically follow the shortest path to the disposal system, the lines are generally not located near large trees or other obstacles. If large trees or other objects are located near the point where the pipe exits the crawlspace or basement, use a probe to follow the path of the sewage pipe around those objects.