Texas, TCEQ, Water System Operator, Class D

Free Texas Class D Water Math Practice

Last reviewed 2026-08-01. Facts link to their official source.

3 free practice modules cover the Class D math on the Texas Class D water operator exam that TCEQ confirms at this grade: unit conversions, chlorine dosage, and tank volumes. Every problem uses fresh numbers, shows all ten worked steps, and saves your progress on this device.

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Where these modules fit in the official exam

The official subject list this module serves
Eight official Need-to-Know subjects: Rules/Regulations; Safety; General; Groundwater; Surface Water; Storage/Distribution; Disinfection; Math.
Source: TCEQ Water Operator Exam Knowledge ('Need-to-Know Criteria for Class D Water Operators' table.)
The official math scope
Class D math: use common conversion units from a table of equivalents; solve basic water utility problems using area, volume, and chemical dosage formulas.
Source: TCEQ Water Operator Exam Knowledge (Class D criteria, 'Math' row (detention time first appears in the Class C criteria).)