Studying for a South Dakota water or wastewater operator exam? You're in the right place. Pick your discipline below: each tab has the certification levels, how South Dakota names them, and the practice tests that match.
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Choose your certification
How South Dakota classifies drinking-water operators
South Dakota DANR certifies four operational categories, and each one is subdivided into Classes I through IV with Class IV the highest and most complex.
Full breakdown in the FAQ below.
Choose your South Dakota certification
Water Treatment (Classes I through IV, rated on plant points)
South Dakota Class I, Water Treatment Practice Test
Class I covers treatment plants rated at 30 points or fewer. Education and experience is a high school diploma plus one year, with no substitution allowed on that year.
DANR · Class II (31-55 points)South Dakota Class II, Water Treatment Practice Test
Class II covers plants rated 31 to 55 points. It takes a diploma plus three years at a Class I facility, or two years at Class II or higher.
DANR · Class III (56-75 points)South Dakota Class III, Water Treatment Practice Test
Class III covers plants rated 56 to 75 points. Two years of college plus four years experience including two at Class II or higher, or a diploma plus six years including three at Class II or higher.
DANR · Class IV (over 75 points, highest)South Dakota Class IV, Water Treatment Practice Test
Class IV covers plants rated over 75 points and is the highest class. A four-year degree plus four years including two at Class III or higher, or a diploma plus eight years including four at Class III or higher.
Small Water Treatment System (a shorter Class I route)
South Dakota wastewater practice tests
Wastewater in South Dakota splits into two of DANR's four categories, treatment and collection, each running Classes I to IV with IV the highest. Treatment plants are rated on a points score for their processes rather than on population: 30 points or fewer is Class I, 31 to 55 is Class II, 56 to 75 is Class III, and over 75 is Class IV. Collection systems are rated on population instead and are covered under Collections. Certification is required once a wastewater treatment plant or collection system serves 500 people or a population equivalent of 500; smaller systems are encouraged to certify voluntarily but are not obliged to. Lagoon operators get a genuinely easier route: the Class I Stabilization Pond and Small Wastewater System exam is 50 questions purely about ponds, where the full Class I Wastewater Treatment exam is 110 questions covering mechanical plants as well.
Wastewater Treatment (Classes I through IV, rated on plant points)
South Dakota Class I, Wastewater Practice Test
Class I covers plants rated at 30 points or fewer. If your facility is a stabilization pond, you can sit the shorter pond exam instead, covered below.
DANR · Class II (31-55 points)South Dakota Class II, Wastewater Practice Test
Class II covers plants rated 31 to 55 points: conventional secondary treatment and routine process control.
DANR · Class III (56-75 points)South Dakota Class III, Wastewater Practice Test
Class III covers plants rated 56 to 75 points: advanced biological treatment, nutrient removal and solids handling.
DANR · Class IV (over 75 points, highest)South Dakota Class IV, Wastewater Practice Test
Class IV covers plants rated over 75 points, the largest and most complex facilities in the state.
Stabilization Ponds (a shorter Class I route)
Water distribution is one of South Dakota's four separate categories, classified purely on the population served: Class I up to 1,500 people, Class II from 1,501 to 15,000, Class III from 15,001 to 50,000, and Class IV at 50,000 or more. Every community and non-transient non-community water system in the state must have a certified water distribution operator, which makes this the most widely needed certificate South Dakota issues. Two situations land you here rather than in water treatment: a groundwater system that does not treat the water at all is classified as a distribution system, and so is any system that buys its water from another supplier such as a rural water system. A Very Small Water System, meaning one serving under 500 people with no treatment, needs a Water Distribution certificate. Note also that if a certified operator is away from the job for more than a month, the system has to bring in another certified operator.
South Dakota Class I, Water Distribution Practice Test
Class I covers systems serving up to 1,500 people, and it is the certificate a Very Small Water System operator needs. Mains, valves, hydrants, storage and safety basics.
DANR · Class II (1,501-15,000)South Dakota Class II, Water Distribution Practice Test
Class II covers 1,501 to 15,000 people: main disinfection, flushing, cross-connection control and pressure management.
DANR · Class III (15,001-50,000)South Dakota Class III, Water Distribution Practice Test
Class III covers 15,001 to 50,000 people: hydraulics, pumping and storage operation, and distribution system water quality.
DANR · Class IV (50,000+, highest)South Dakota Class IV, Water Distribution Practice Test
Class IV covers systems serving 50,000 or more: system-wide planning, capital work and regulatory compliance for the largest networks.
Wastewater collection is a full certification category in South Dakota, separate from the treatment plant ladder, and it uses exactly the same population bands as water distribution: Class I up to 1,500 people, Class II from 1,501 to 15,000, Class III from 15,001 to 50,000, and Class IV at 50,000 or more. The threshold that matters is 500: a collection system needs a certified operator once it serves 500 people or a population equivalent of 500. Below that, DANR recommends certification but does not require it. Your experience must be in collection specifically, since South Dakota does not let you sit an exam in a category you have not worked in.
South Dakota Class I, Collection System Practice Test
Class I covers collection systems serving up to 1,500 people: pipe, manholes, basic maintenance, safety and confined space awareness.
DANR · Class II (1,501-15,000)South Dakota Class II, Collection System Practice Test
Class II covers 1,501 to 15,000 people: cleaning and inspection, lift station operation, infiltration and inflow, and overflow response.
DANR · Class III (15,001-50,000)South Dakota Class III, Collection System Practice Test
Class III covers 15,001 to 50,000 people: pump station hydraulics, force mains, odor and corrosion control, and rehabilitation methods.
DANR · Class IV (50,000+, highest)South Dakota Class IV, Collection System Practice Test
Class IV covers systems serving 50,000 or more: asset management, capacity assurance, capital planning and regulatory reporting.
About the South Dakota operator exams
Operator certification in South Dakota covers several disciplines, drinking water, wastewater, distribution, and collections, which may be handled by the same agency or by separate programs (drinking water is administered by South Dakota DANR (Department of Agriculture and Natural Resources), Board of Operator Certification, SDCL Ch. 34A-3 / ARSD 74:21:02). The exact certification structure, exam format, levels, and continuing-education requirements vary by discipline and change over time, so always confirm the current scope and eligibility directly with the certifying agency. Our practice content focuses on the underlying technical material: the same operating principles, math, regulations, and process knowledge that show up on water and wastewater operator exams nationwide.
Frequently asked questions
How does South Dakota classify water operators?
Are these the exact questions on the South Dakota exam?
Are these practice tests free?
Disclaimer: WaterOperatorPracticeTest.com is an independent study aid. We are not affiliated with South Dakota DANR (Department of Agriculture and Natural Resources), Board of Operator Certification, SDCL Ch. 34A-3 / ARSD 74:21:02 or any state primacy agency. Always confirm current exam requirements with your state's certification body.