Wastewater Operator III

Applications closing on September 28, 2026, 11:59 PM

• Reference number
• Job Type Full Time

The City of Caldwell Wastewater Treatment Plant is looking for an Operator III to join their team. Individual performs a variety of general labor and skilled tasks related to the operation, maintenance and repair of wastewater treatment equipment at wastewater collections and treatment facilities; operates heavy equipment; performs related work and tasks as required.

The principal function of an employee in this class is to perform general labor, semi-skilled and skilled tasks related to the operation, maintenance and repair of wastewater treatment equipment to ensure efficient operation of plant components and efficient processing of influent raw sewage. A function of this position is contact and cooperative work with the wastewater treatment plant employees, general public, City employees, and other government agencies.

The work is performed under the direct supervision of the superintendents. This position is distinguished from the Operator II position by the possession of a Class III Wastewater Treatment Operator License and an understanding of supervisory responsibilities. The principal duties of this class are performed in an outdoor environment; daily potential for hazardous exposure to methane, hydrogen sulfide, chlorine gases, sodium bisulfate, acids and other chemicals;

daily potential for hazardous exposure to oxygen deficient atmosphere; daily potential for hazardous exposure to electrical shock, ultraviolet light, industrial wastes and raw sewage; daily exposure to moving parts and equipment.

Individual will work 4 days a week with 10-hour workdays. Saturday, and Sunday required to work. Flexible on a weekday hours.

• Performs routine tasks related to facilities and grounds upkeep and maintenance;
• Cleans building, equipment, primary and secondary clarifiers;
• Performs environment upkeep, mowing lawns, snow removal, etc;
• Performs interior and exterior painting;
• Operates tractors, dump trucks, etc. as needed;
• Operates and assists in operation of light to heavy equipment in cleaning and maintaining plant facility;
• Assists in treatment plant processes and operations, including plant electrical and mechanical support systems to ensure optimum performance;
• Checks all equipment, including electrical, mechanical, hydraulic, pneumatic, and biological to ensure proper operations;
• Operates and maintains plant support systems, including stepping screens, grit removal equipment, sludge pumps, boilers, heat exchangers, greasers, oilers, clarifiers, aeration equipment, digesters, gas equipment, dissolved air floatation system, ultra violet disinfection, gravity belt thickener, belt filter press, sampling, and metering equipment, emergency power generation equipment, and all associated valves, pumps, motors, and control circuitries;
• Documents findings, efforts and activities in course of duties in a paper log and/or digital log format;
• Monitors plant alarm systems and supervisory control and date acquisition (SCADA) system;
• Assists operation and maintenance of ultra violet disinfection system;
• Assists in laboratory samples from various stages of treatment process;
• Calibrates gauges, meters and measuring devices;
• Performs a variety of laboratory tests, such as dissolved oxygen and pH, total suspended solids, sludge volume index, percent solids, and other tests and procedures;
• Interprets laboratory test results to evaluate plant performance;
• Uses mathematical calculations in figuring detention times, flow rates, areas, volumes, pumping rates, mixed liquor suspended solids, percent solids, volatile suspended solids destruction/reduction, etc;
• Performs and assists with maintenance and…