We have lived in our home for over 3 years. We have 2 sump pits, each with a pump. The second pit is operated with a battery back up in case of power failures. Recently, we have found that the back up pump is going off every 3 hours or so. The primary operates only sporadically. I know we have water entering the pits normally during periods of no rain due to the water table but I am confused why this would suddenly start happening in the second pit.