Big Sewer Problem 

While working on a home that was experiencing water issues. Sometimes they would have up to 3-4" of water on top of the basement slab.
As part of the project we cut the entire perimeter of the basement and dug out the old clay drain tile system and installed a new drain tile system and 3/4" rock. We discovered that the original plumber had not connected the drain tile to the sewer drain system. This home was built decades ago. The drain tile pipe ended in the soil and about 6" and 90 degrees counter clockwise was the open end of the sewer.
It only took a few years or less for it to be hopelessly clogged.