Isle Royale Ballast Test Results

Isle Royale National Park is continuing its efforts to prevent the spread of aquatic invasive species. The park released reports on its ballast water treatment technology on one of its ships, the Ranger III. A reponse treatment using chlorine, a filtration system and ultra-violet technology was used to detect invasive species in the ballast water discharge. The system passed U.S. Federal and international standards for two requirements: discharge for living zoo plankton and indicator bacteria. It did not meet the standards for phytoplankton, which are some of the toughest organisms to kill. Isle Royale personnel say they hope the system will soon pass approval testing so a more permanent system will be available for all sizes and classes of fresh water ships.