Texas Wastewater Operator License: Class D to A Steps
Texas licenses wastewater treatment operators through the Texas Commission on Environmental Quality (TCEQ) Occupational Licensing program, under 30 TAC Chapter 30, Subchapter J. The entry license needs no experience at all, which makes Texas one of the easier states to break into. Here's the path from no license to Class A.
Requirements and fees change. Always confirm the current details on TCEQ's wastewater operator license page before you apply. This guide is an overview, not the rulebook.
Key takeaways
- Wastewater treatment licenses run Class D (entry) to Class A (highest). Collection is a separate Class I to III ladder.
- Class D needs a high-school diploma or GED and the Basic Wastewater Operation course. No experience required.
- Exams are taken at TCEQ-approved computer-based testing centers. You need 70%, and the application fee is $111.
- Licenses renew every 3 years with 30 hours of continuing education.
- Practice with the free Texas tests, starting with Wastewater Class 1.
Step 1: Know which license your plant needs
Every treatment plant has a category, and the chief operator's license must be at least that category. Shift operators can hold one level below. TCEQ sets the category by treatment type and permitted flow (license level table):
| Plant type | Class D | Class C | Class B | Class A |
|---|---|---|---|---|
| Extended aeration / oxidation ditch | up to 0.10 MGD | up to 1.0 | up to 10 | over 10 |
| Other activated sludge | up to 0.050 MGD | up to 1.0 | up to 10 | over 10 |
| Trickling filter / RBC / fixed film | up to 0.50 MGD | up to 2.0 | up to 10 | over 10 |
| Ponds | up to 1.0 MGD | over 1.0 |
A Class D plant moves up to Class C if it has anaerobic digestion (Imhoff tanks excepted), nutrient reduction, or a BOD or TSS limit below 10 mg/L.
Step 2: Meet the requirements for your class
TCEQ's requirements sheet sets education, experience and courses for each class:
| Class | Education and experience | Required courses |
|---|---|---|
| D | HS diploma or GED, no experience | Basic Wastewater Operation |
| C | HS/GED + 2 years (at least half in the field) | Basic Wastewater Operation, Activated Sludge or Wastewater Treatment, plus 1 elective |
| B | Bachelor's + 2.5 years hands-on, or HS/GED + 5 years (3 hands-on) | The Class C courses plus Collection, Lab and Safety, plus 1 elective |
| A | Master's + 4 years hands-on, bachelor's + 5 years hands-on, or HS/GED + 8 years (6 hands-on) | The Class B core plus Water Utility Management, plus 1 elective |
Degrees must be in a relevant field. If you have a high-school diploma or GED, college credit or extra training can stand in for some experience: 32 semester hours or 40 training hours = 1 year (half that for 6 months), up to 1 year for Class C and 2 years for Classes B and A.
No diploma or GED? TCEQ issues a Provisional Class D for $74. You still take Basic Wastewater Operation, and you must upgrade to Class D or higher within its 2 years.
Step 3: Take the exam
Once TCEQ approves your application, you test at a TCEQ-approved computer-based testing center, mostly community colleges, listed by region on TCEQ's exam page. What to expect:
- 3 hours for most exams. The Class A wastewater exam gets 6 hours.
- 70% to pass. Your score shows up right away.
- A non-programmable calculator is allowed. The exam is not open book.
- The $111 application fee goes to TCEQ. Each testing center sets its own exam fee.
- You can't retake until your last result is in. Your application expires after 365 days or 4 failed attempts at the same exam, whichever comes first.
Math shows up at every class. The wastewater operator math formulas guide and the free wastewater math practice test cover what's on it.
Step 4: Know the on-the-job rules
- A treatment license also covers collection duties. A collection license covers collection only.
- The chief operator, or someone at the required level, must run the plant at least 5 days a week and be reachable by phone 7 days a week.
- New hires can work up to 1 year as operators-in-training, doing process control only with a licensed operator present.
Step 5: Renew every 3 years
All wastewater licenses renew every 3 years with 30 hours of continuing education, finished before the license expires (renewal requirements). Two things catch people out:
- Class D can't be renewed by operators of activated sludge plants of any size, trickling filter or RBC plants at 0.1 MGD or more, or subsurface drip plants. Plan to move up to Class C.
- Classes A and B can't count Basic Wastewater Operation toward renewal.
The fee is $111 on time, rising to $166.50 up to 90 days late and $222 up to 180 days late. After 180 days you have to reapply and test again. Renewal by exam instead of continuing education ended in March 2025.
Moving to Texas with a license
TCEQ handles reciprocity case by case with some states and doesn't publish a list. Contact TCEQ before you assume your license transfers.
Next steps
- Check current requirements and forms on TCEQ's wastewater license page.
- Practice: Class D, Class C, Class B, Class A, or the Texas wastewater flashcards. The 30-day wastewater study plan lays out a schedule.
- Working on the water side too? See how to get a Texas water operator license.
Sources: TCEQ wastewater license, requirements, license-level and renewal pages; 30 TAC Chapter 30. Reviewed October 2026.