Foundation walls are surprisingly complicated things because they have to hold up the weight of the house, resist the pressure from the ground surrounding them, and keep the basement dry and warm.
This drain tile or weeping tile system may have been installed at the time of original construction or part of a retrofit basement waterproofing system. Depending on the type of waterproofing system installed, the tile may have been installed on either the inside or the outside of the basement or foundation wall.
A sump pump and tile system removes water that would otherwise collect at the foundation footing, causing considerable damage inside the home. A stand-alone sump pump system can sometimes be used to collect water from below a basement floor where a high water table and hydrostatic pressure may be an issue.
In such cases water will typically be seen seeping through cracks or fissures in the basement floor. Click here to learn more about possible waterproofing solutions that may be required to solve your wet basement issue.
In some locales, sump pits and pumps are part of the building code.