Production · Holland code RCI

Water and Wastewater Treatment Plant and System Operators

Operate or control an entire process or system of machines, often through the use of control boards, to transfer or treat water or wastewater.

Also called: Wastewater Operator (WW Operator), Water Plant Operator, Water Treatment Operator, Water Treatment Plant Operator, Plant Operator, Process Operator (Process Op), Relief Operator, Waste Water Treatment Plant Operator (WWTP Operator).

O*NET 51-8031.00

At a glance

US median annual pay: $60,020; Middle half earn $48,040 to $74,780. BLS OEWS, May 2025.
Most common education: High School Diploma or the equivalent (such as a GED); 50% of workers surveyed by O*NET report this level.
Preparation needed: Job Zone 2 of 5; Some preparation. Zone 1 is little or none; zone 5 is graduate-level.
US employment outlook, 2024 to 2034: -7% · Decline; 132,400 jobs in 2024, projected 123,800. BLS Occupational Outlook Handbook, which groups this with similar roles as "Water and wastewater treatment plant and system operators".

What the work involves

The tasks workers in this occupation rate as most important, from the O*NET survey.

Collect and test water and sewage samples, using test equipment and color analysis standards.
Operate and adjust controls on equipment to purify and clarify water, process or dispose of sewage, and generate power.
Record operational data, personnel attendance, or meter and gauge readings on specified forms.
Add chemicals, such as ammonia, chlorine, or lime, to disinfect and deodorize water and other liquids.
Inspect equipment or monitor operating conditions, meters, and gauges to determine load requirements and detect malfunctions.
Direct and coordinate plant workers engaged in routine operations and maintenance activities.
Clean and maintain tanks, filter beds, and other work areas, using hand tools and power tools.
Maintain, repair, and lubricate equipment, using hand tools and power tools.

Skills and knowledge it leans on

Skills

Monitoring3.6 / 5
Active Listening3.1 / 5
Speaking3.1 / 5
Reading Comprehension3.0 / 5
Critical Thinking3.0 / 5
Mathematics2.9 / 5

Knowledge areas

Public Safety and Security4.2 / 5
Mechanical3.6 / 5
English Language3.5 / 5
Chemistry3.4 / 5
Administration and Management3.4 / 5
Mathematics3.4 / 5

Importance ratings on O*NET’s 1 to 5 scale. Higher means the occupation depends on it more.

Who tends to enjoy it

How strongly this occupation draws on each of the six Holland interest types, which is the same profile the career interests test compares you against.

Realistic96
Investigative26
Artistic0
Social10
Enterprising10
Conventional60

The same work abroad

Other countries classify jobs differently, so these are the closest matches through the international ISCO-08 standard, not exact equivalents.

European occupation titles (ESCO)

water treatment plant manager · DE Leiter einer Wasseraufbereitungsanlage/Leiterin einer Wasseraufbereitungsanlage · FR responsable d'usine d'épuration des eaux
desalination technician · DE Entsalzungstechniker/Entsalzungstechnikerin · FR technicien en désalinisation/technicienne en désalinisation
liquid waste treatment plant operator · DE Steuerer von Flüssigabfallaufbereitungsanlagen/Steuerin von Flüssigabfallaufbereitungsanlagen · FR conducteur d’installations de traitement de déchets liquides/conductrice d’installations de traitement de déchets liquides
wastewater treatment operator · DE Steuerer von Abwasseraufbereitungsanlagen/Steuerin von Abwasseraufbereitungsanlagen · FR conducteur d’installations de traitement des eaux/conductrice d’installations de traitement des eaux
wastewater treatment technician · DE Abwasseraufbereitungstechniker/Abwasseraufbereitungstechnikerin · FR technicien de station d’épuration/technicienne de station d’épuration
water plant technician · DE Wasserwerker/Wasserwerkerin · FR technicien d’exploitation eau potable/technicienne d’exploitation eau potable

Closest UK occupation groups (SOC 2020)

Pipe fitters (5214)3,700 employed
Plumbers and heating and ventilating installers and repairers (5315)153,700 employed
Water and sewerage plant operatives (8134)21,000 employed

Employment is the UK Annual Population Survey for April 2025 to March 2026, all workers in the group, which can be broader than this one occupation.

Pay across Europe, for the whole group

Median annual earnings of all employees in “Technicians and associate professionals”. This is the broad ISCO group this occupation falls in, not the occupation itself, so treat it as context for the wage level, not as a salary for this job.

Median annual earnings, Technicians and associate professionals, by country
Country	Median pay
Belgium	€50,992
Austria	€46,986
Germany	€44,473
Netherlands	€42,448
Ireland	€41,613
Sweden	€41,155
Italy	€34,882
France	€34,816
Spain	€29,757
Portugal	€18,080
Poland	€12,108

Eurostat Structure of Earnings Survey, businesses with ten or more employees outside public administration, in euro and not adjusted for the cost of living. Reference years differ between sources: the US, Japan and Europe figures on this page come from different survey years, so compare them as rough levels, not to the euro or yen.

Exposure to AI

This occupation sits in the middle third of the 774 occupations scored, with an exposure score of -0.45. The scores are standardized across those occupations, so 0 is the average and a score of 1 is about one standard deviation above it.

Our note on reading it: the dataset links AI applications to the abilities that occupations require, so the score reflects overlap between the two. It is a comparison between occupations, not a forecast about jobs. It does not say whether exposure means tasks are replaced or workers get more done with the tools, and it says little about one employer or one role.

Source: Felten, E., Raj, M., & Seamans, R. (2021). Occupational, industry, and geographic exposure to artificial intelligence: A novel dataset and its potential uses. Strategic Management Journal, 42(12), 2195-2217. Matched to this page by 6-digit SOC code (51-8031).

Is it a fit for you?

Interest is one input, alongside ability, pay and what is hiring near you. The career interests test takes about thirteen minutes and ranks occupations by how closely their profile matches yours.

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