We have an old cistern under our home. We've lived in the house for 8 years and never noticed it until last year. The basement is under our living room and kitchen area, the rest of the house has a wooden foundation and that is where this cistern is. Starting last spring it started to overflow pouring mud and water into our basement. That's how we discovered it. It is covered over with a cinderblock. This year it continues to fill and pour over into the basement. We do have an area in the basement itself for a sump pump, but we dont have one. Any advice? I work at a home repair store where we sell shallow well pumps, & sump pumps. But I dont know where to begin here. What would cause it to overfill after all this time? And how should I handle this?