TCEQ Class D Water Practice Test
Original questions written to TCEQ’s Need-to-Know Criteria for this license, every option explained.
Which pump type is common in deep wells, with stages of impellers hung on a long shaft or driven by a submersible motor?
259 original TCEQ Class D Water questions with explanations · 100-question practice exam · 8 subjects
TCEQ Class D Water exam format
The Texas Commission on Environmental Quality licenses public water system operators. Class D is the entry license; its Need-to-Know Criteria cover rules, safety, general knowledge, groundwater, surface water, storage and distribution, disinfection and math. You need 70 percent to pass, at a TCEQ-approved computer-based testing center.
- Subjects (TCEQ Need-to-Know)
- Rules/Regulations, Safety, General, Groundwater, Surface Water, Storage/Distribution, Disinfection, Math
- Where
- At a TCEQ-approved computer-based testing (CBT) center after TCEQ approves your application; scores are immediate
- Passing score
- 70 percent
- Fees
- TCEQ application $111 ($74 provisional Class D); each CBT center sets its own testing fee
- Allowed aids
- A non-programmable calculator; scratch paper from the proctor. No books or notes
- Questions and time
- TCEQ does not publish the number of questions or the time limit for this exam
- Requirements
- High school diploma or GED; no work experience. A provisional Class D (two years) is issued to applicants without a diploma or GED
- Required training
- Basic Water Operations and Resiliency Overview
What’s on the TCEQ Class D Water exam
TCEQ lists these subjects without question counts. Our practice exam gives each subject an equal share; each row links to the free topic drills that practice it.
| Subject | What it covers | Our practice exam | Drill |
|---|---|---|---|
| Rules/Regulations | 30 TAC Chapter 30 licensing and Chapter 290 drinking water rules | 12 | Regulations drill |
| Safety | Safety procedures, equipment and hazards | 12 | Safety drill |
| General | Public health, bacteriological sampling, customer relations, records, cross-connections and inspections | 13 | Water lab drillBackflow drillManagement drill |
| Groundwater | Well parts and protection, pumps and motors, groundwater treatment | 13 | Source water drillPumps and equipment drill |
| Surface Water | Surface water sources and treatment processes | 12 | Coagulation and filtration drillCorrosion and chemistry drill |
| Storage/Distribution | Storage, distribution parts, meters, valves and pipe | 13 | Mains and valves drillHydraulics drillPumps and equipment drill |
| Disinfection | Chlorinators, chlorine forms and hazards, residual testing and first aid | 13 | Disinfection drill |
| Math | Conversions, area, volume and dosage | 12 | Water math drill |
How to take the TCEQ Class D Water exam
- Complete the required training (Basic Water Operations and Resiliency Overview) and meet the education and experience rules.
- Submit the TCEQ application and $111 fee (online through OLEA or by mail).
- Once TCEQ approves the application, schedule the exam at a TCEQ-approved computer-based testing center and pay its testing fee.
- Score 70 percent or more; results are immediate, and some centers offer one retest the same day.
Common questions
What is on the TCEQ Class D Water exam?
TCEQ's Need-to-Know Criteria list the subjects: Rules/Regulations, Safety, General, Groundwater, Surface Water, Storage/Distribution, Disinfection, Math. TCEQ does not publish how many questions each subject gets.
What score do I need to pass?
TCEQ requires a minimum score of 70 percent.
How many questions are on the exam?
TCEQ does not publish the question count or time limit for this exam. Our practice exam has 100 questions on a 3-hour clock so you can practice at full length.
What can I bring to the exam?
A non-programmable calculator. The proctor supplies scratch paper and collects it. Phones, books and notes are not allowed.
Are these the real TCEQ questions?
No. TCEQ prohibits sharing or copying exam content. These are original questions written to TCEQ’s published Need-to-Know Criteria, with an explanation for every option.
Ready for exam day?
100 questions across the published subjects, with a score for every area and an explanation for every option.
Or start with a free ten-question drillMore Texas exam practice
One water operator pass covers every practice exam on the site.
Requirements, subjects, fees and pass mark checked November 2026 on tceq.texas.gov: TCEQ: Public Water System Operators licensing requirements · TCEQ: Need-to-Know Criteria for public water system operators · TCEQ: Licensing exams (computer-based testing, authorized aids) · TCEQ: Continuing education hours to renew by license type (PDF).
Game Assessment Prep is an independent practice site, not affiliated with or endorsed by Water Professionals International (WPI, formerly ABC), the California State Water Resources Control Board or the Texas Commission on Environmental Quality. Every question is original; none is taken from a certification exam, an official study guide or another prep provider.