 An online fundraiser is underway to support the family who owns the Rapidan Dam store near Mankato, as well as an adjacent house that was swept away by the rain-swollen Blue Earth River. The river has carved a new channel around the more-than-century-old dam. After the house fell into the water Tuesday night, further erosion could endanger the building housing this store, as well as a county highway bridge. Louise Henderson is a friend of the Hershka family, which has owned the store for decades.