Dam's were decommissioned because they were deemed hazardous thanks to their poor water quality thanks to acid mine runoff and water borne radioactive materials (incl uranium) making it unsafe to the public, who utilized the dams for recreation (Tudor and Lancaster dams) and for living (e.g fishing for food, drinking water for cattle and irrigation), Harry's dam was also leaking water into the dewatered compartments causing problems for the mining companies responsible for the dewatering.