Water treatment facility classifications

Water treatment facilities must be classified in one of five classes. Classifications must be based on population served, design population, type of treatment, raw water quality and volume of water to be treated, and complexity of sludge handling units. Facilities may be classified at the discretion of the department if the facility has special design features or complex features or characteristics unusually difficult to operate, by reason of raw water unusually difficult to treat, volume of water treated, or a combination of such conditions or circumstances. 1. Class IA. All water facilities using simple chemical or physical treatment processes and designed to serve a population of less than five hundred persons. 2. Class I. All water facilities using chemical treatment processes and designed to serve a population of five hundred to five thousand persons. This includes water facilities utilizing disinfection, fluoridation, corrosion control, sequestering, or combinations of these processes or other processes that involve simple chemical addition and a minor degree of operational control. 3. Class II. a. All water facilities using chemical treatment processes and designed to serve a population of five thousand to fifteen thousand persons. This includes water facilities utilizing disinfection, fluoridation, corrosion control, sequestering, or combinations of these processes or other processes that involve simple chemical addition and a moderate degree of operational control. b. All water plants using chemical softening processes and filtration requiring a moderate degree of operational control serving a population of less than one thousand persons. c. All water plants using coagulation, sedimentation, and filtration for clarification requiring a moderate degree of operational control serving a population of less than one thousand five hundred persons. d. All water plants using chemical oxidation of iron or manganese and filtration requiring a moderate degree of operational control serving a population of less than two thousand persons. e. All water plants using processes requiring a moderate degree of operational control but not listed in subdivisions b, c, and d and serving a population of less than two thousand persons. 4. Class III. a. All water facilities using chemical treatment processes and designed to serve a population of fifteen thousand persons or more. This will include water facilities utilizing disinfection, fluoridation, corrosion control, sequestering, or combinations of these processes or other processes that involve simple chemical addition and a high degree of operational control. b. All water plants using chemical softening processes and filtration requiring a high degree of operational control serving a population of one thousand to five thousand persons. c. All water plants using coagulation, sedimentation, and filtration for clarification requiring a high degree of operational control serving a population of one thousand five hundred to ten thousand persons. d. All water plants using chemical oxidation of iron or manganese and filtration requiring a high degree of operational control serving a population of two thousand to fifteen thousand persons. e. All water plants using processes requiring a high degree of operational control but not listed in subdivisions b, c, and d and serving a population of two thousand to fifteen thousand persons. 5. Class IV. a. All water plants using chemical softening processes and filtration requiring a high degree of operational control serving a population of five thousand or more persons. b. All water plants using coagulation, sedimentation, and filtration for clarification requiring a high degree of operational control serving a population of ten thousand or more persons. c. All water plants using chemical oxidation of iron or manganese and filtration requiring a high degree of operational control serving a population of fifteen thousand or more persons. d. All water plants using processes requiring a high degree of operational control but not listed in subdivisions a, b, and c and serving a population of fifteen thousand or more persons.