Choose your track

Water vs. wastewater operator

Water and wastewater are separate Texas Class D licenses with separate exams, and the two are never mixed. Most operators pick the one that matches their job, and many go on to hold both. Here is how they compare so you can choose with a clear head.

What you operate

Water

The system that treats and delivers safe drinking water: wells or surface intakes, treatment, storage tanks, and the distribution pipes to customers.

Wastewater

The plant that cleans used water before it returns to the environment: collection lines, treatment stages, disinfection, and solids handling.

What the exam covers

Water

Eight official subjects, including groundwater, surface water, storage and distribution, disinfection, and operator math.

Wastewater

Twenty official subjects, from collection and pumping through the treatment stages, process control, solids, and operator math.

The math you will see

Water

Unit conversions, area and volume, and chlorine dosage. Steady, learnable, and worked step by step.

Wastewater

The same conversions, area, volume, and dosage, plus flow rate in MGD, GPM, and GPD.

Who it usually fits

Water

Anyone helping run a public water system, especially a small groundwater system, or moving into that work.

Wastewater

Anyone working at or moving toward a wastewater treatment facility or collection system.

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