Drain tiles serve as a means by which ground water can be moved away from your basement. If you want a dry basement, you must have an adequate foundation drainage system.
The water content in the soil can be very high due to the amount of rain Delta and the lower mainland receives. Digging will always bring up some amount of water. This is referred to as to this as the water table. This water table rises and falls in response to the amount of precipitation in any given time period.