State directory
Water operator requirements, state by state.
Choose a state to find its regulator, credential types, renewal cycle, continuing-education requirements, reciprocity path, and official sources.
Alabama
Water treatment Grades I-IV; wastewater Grades IC, I-IV. Division 10 also covers water distribution systems and public wastewater collection systems.
Alaska
Water Treatment, Water Distribution, Wastewater Treatment, and Wastewater Collection: Provisional and Levels 1-4; also Small Treated, Small Untreated, and Wastewater Stabilization Pond certificates.
Arizona
ADEQ covers water treatment, distribution, wastewater treatment, and wastewater collection.
Arkansas
Drinking water: Treatment Grades I-IV and Distribution Small System/I-IV. Wastewater: Municipal Classes I-IV, Industrial Basic/Advanced, collection licensing, and apprentice/OIT pathways; collection reciprocity is expressly excluded.
California
Separate state programs govern drinking-water treatment/distribution and wastewater treatment operators.
Colorado
Water treatment, domestic wastewater treatment, and industrial wastewater treatment Classes D-C-B-A; distribution and collection Classes 1-4; additional T and S classes appear in renewal table.
Connecticut
Drinking water: WTP Classes I-IV, Distribution Classes I-III, Small Water System, and WTP/DS operator-in-training. Wastewater: Classes I-IV with OIT for I-III.
Delaware
Wastewater Classes I-IV and OIT. Drinking water: base-level water-supply operator plus disinfection, chemical feed, filtration, surface-water operations, other specified treatment, distribution and approved sampler/tester endorsements; specialty OIT, grandfather, limited and distribution licenses.
Florida
Water treatment and wastewater treatment Classes D, C, B, A (A highest); water distribution Levels 4, 3, 2, 1 (1 highest).
Georgia
Water operator Classes IV-III-II-I; wastewater operator Classes IV-III-II-I; groundwater Class III; water distribution; wastewater collection; industrial wastewater; water/wastewater laboratory analyst.
Hawaii
Public water-system water treatment and distribution Grades 1-4; wastewater treatment Grades 1-4.
Idaho
Drinking-water treatment/distribution and wastewater treatment/collection: OIT, restricted/lagoon/land-application where applicable, Classes I-IV; drinking-water and wastewater Very Small System; wastewater laboratory analyst Classes I-IV; backflow tester.
Illinois
Community drinking-water supply operators: Classes A, B, C, D. Wastewater: municipal treatment classes and separate industrial Class K; collection-system certification is voluntary.
Indiana
Drinking-water distribution DSS/DSM/DSL and treatment WT1-WT5. Wastewater has ten sanitary/industrial classifications including A-SO, A-D, I-SP, and I-IV.
Iowa
Iowa DNR certifies drinking-water treatment, distribution, and wastewater treatment operators.
Kansas
Water treatment, water distribution, and wastewater treatment/operator certification.
Kentucky
Kentucky covers drinking-water, distribution, wastewater, collection, bottled-water, and limited credentials.
Louisiana
LDH certifies water production, treatment, distribution, wastewater treatment, and collection operators.
Maine
Public water-system operators; wastewater treatment operators including SITS-1.
Maryland
Water, wastewater, industrial wastewater, water distribution, wastewater collection, and superintendent/OIT pathways.
Massachusetts
Drinking-water treatment (T), distribution (D), very-small-system/non-community credentials; wastewater treatment-plant operator credentials.
Michigan
Drinking-water Levels 1-5; municipal wastewater A, B, C, D, L1, L2, SC; industrial wastewater Levels 1-3.
Minnesota
Separate state programs govern drinking-water and wastewater operators.
Mississippi
Public water-supply operator certification; Wastewater operator certification (separately administered)
Missouri
Drinking Water Treatment; Drinking Water Distribution; Wastewater Treatment; CAFO Waste Management Systems
Montana
1A–4A Water Distribution; 1B–4B Water Treatment; 1C–3C Municipal Wastewater; 1D–4D Industrial Wastewater; 2E–4E On-site Wastewater
Nebraska
Water Operator Grades I–VI; Professional Wastewater Operator certification by facility/type and grade
Nevada
Drinking Water Treatment; Drinking Water Distribution; Wastewater Treatment Plant Operator
New Hampshire
Water Treatment; Water Distribution; Wastewater Treatment
New Jersey
N Industrial Wastewater; C Public Wastewater Collection; S Public Wastewater Treatment; W Public Water Distribution; T Public Water Treatment; VSWS Very Small Water System
New Mexico
Water Supply; Water Treatment; Wastewater Treatment; Small-system and category credentials administered by UOCP
New York
Drinking Water Treatment Operator/Assistant; Drinking Water Distribution; Wastewater Activated Sludge Grades 1A–4A; Wastewater Non-activated Sludge Grades 1–4
North Carolina
Drinking Water Treatment; Drinking Water Distribution; Biological Wastewater; Wastewater Collections; Land Application; Physical/Chemical; Subsurface; Surface Irrigation
North Dakota
Water treatment, water distribution, wastewater treatment and wastewater collection in Classes IA, I, II, III and IV, aligned to the regulated facility/system category and class.
Ohio
Water supply and water reclamation Classes A, I-IV; water distribution Classes I-II; wastewater collection Classes I-II; limited/facility-specific certificates are also authorized.
Oklahoma
Waterworks and wastewater works operator Classes D, C, B, A; water/wastewater laboratory C, B, A; distribution/collection C Operator and Technician; groundwater and lagoon operations are included.
Oregon
Wastewater treatment and collection: Small System and Grades I-IV. Drinking water treatment and distribution: Levels 1-4, Small Water System, and filtration endorsement.
Pennsylvania
Drinking water and wastewater Classes A-D with technology subclasses; wastewater E collection; drinking-water E distribution/consecutive systems; drinking-water Dc and Dn small-system credentials.
Rhode Island
Drinking-water treatment and distribution: VSS and Classes 1-4, full and OIT except no Class 4 OIT. Wastewater treatment: Grades 1-4, with optional Tier Two renewal designation 1T-4T.
South Carolina
Water distribution, water treatment, biological wastewater treatment and physical/chemical wastewater treatment; operator ladder D-C-B-A, with entry water-treatment E and trainee status where applicable.
South Dakota
Water treatment, water distribution, wastewater treatment and wastewater collection Classes I-IV, plus Small Water Treatment and Small Wastewater System.
Tennessee
Water Treatment 1-4; Wastewater Treatment 1-4; Distribution 1-2; Collection 1-2; Small Water System; Biological/Natural System.
Texas
Public Water System Operator and Wastewater Treatment Operator Classes D-C-B-A; Wastewater Collection I-II-III; provisional D pathways exist.
Utah
Drinking water: Small System and treatment/distribution Grades 1-4. Wastewater mandatory credentials: Treatment Grades I-IV, Collection Grades I-IV and Utah Small Lagoon System Grade I; voluntary Laboratory Analyst I-IV, Biosolids Land Applier I-II and Plant Maintenance Technologist I-III. Restricted certificates identify an operator who passed the exam but has not yet met experience/education requirements.
Vermont
Drinking water: OIT and provisional pathways plus Classes 1A, 1B, 2, 3, 4A1, 4A, 4B, 4C and D (distribution). Wastewater: Domestic Grades I-V and Industrial Grades I, II, IV and V; Grade III is not an industrial credential in the rule's classification table.
Virginia
Waterworks operator Classes 1-6 and wastewater works operator Classes 1-4; Class 1 is the highest classification.
Washington
Waterworks: Water Distribution Manager and Water Treatment Plant Operator Grades 1-4, Water Distribution Specialist, Cross-Connection Control Specialist and Backflow Assembly Tester, with operator-in-training pathways where authorized. Wastewater: full and operator-in-training certifications in Groups I-IV.
West Virginia
Public water: 1D, Class R, Water Distribution System (WDS), OIT and Classes I-IV. Wastewater: Classes H, S, C, OIT and I-IV, with an advanced designation available to qualifying Class IV operators.
Wisconsin
Municipal waterworks subclasses D, G, I, L, S, V and Z at Grade T (operator-in-training) and Grade 1; small OTM/NN water-system general-operation certification. Wastewater levels are operator-in-training, Basic and Advanced with process subclasses A1-A5, B, C, D, L, N, P, SS and U.
Wyoming
Water Treatment Levels 1-4; Water Distribution Levels 1-2; Wastewater Treatment Levels 1-4; Wastewater Collection Levels 1-2; Well System; Lagoon System. Operators obtain the desired level and all preceding levels.
Water Operator Guide covers all 50 states using retained official state rules, forms, program pages, and certification resources. Governing authorities remain the final source of truth.