Texas, TCEQ, Wastewater Treatment, Class D
Free Loading Rates Practice: Texas Class D Wastewater
Free loading rates practice problems for the Texas Class D wastewater operator exam. You practice hydraulic and organic pond loading: daily flow and BOD pounds spread across the surface. Every problem uses fresh numbers, checks your answer, and shows all ten worked steps with nothing skipped. Progress saves on your device.
Loading practice
Learn the method
See one problem worked in fullEvery step, from the question to the rounded answer
You practice hydraulic and organic pond loading: daily flow and BOD pounds spread across the surface. This one works hydraulic loading rate from start to finish. Every number traces to the question, a named conversion, or the line before it.
1. What you know
Daily flow: 45000 gpd. Surface area: 900 sq ft.
2. What you need
The daily flow carried by each square foot, in gpd.
3. Match the units
Flow is in gallons per day and the area is in square feet, so the division gives gpd per square foot directly.
4. Choose the formula
Hydraulic loading asks how much daily flow lands on each square foot of surface, so divide the day's flow across the area.
loading = gpd / square feet
5. Put in the values
Put each labeled value into the formula before doing any arithmetic.
gpd/sq ft = 45000 / 900
6. Track the units
The division spreads the day's flow across the area. Gpd per square foot remains.
gal/day / sq ft -> gpd/sq ft
7. Work it
One operation, one line.
45000 / 900 = 50
8. Round at the end
The rule here: round to the nearest whole gpd per square foot at the end. 50 becomes 50 gpd/sq ft.
9. Check the answer
50 gpd per square foot, multiplied back by the area, rebuilds the daily flow. The unit left is gpd per square foot, which is what the question asked for.
10. What it means
Ponds and sand filters are permitted for a loading range. This number is how you compare today's flow against what the surface was designed to take.
Formulas and where each number comes fromThe formula for each shape, plus every conversion and constant
Hydraulic loading rate
loading = gpd / square feet
Hydraulic loading asks how much daily flow lands on each square foot of surface, so divide the day's flow across the area.
Where this fits on the official examThe TCEQ subjects and math scope this module serves
- The official subject list this module serves
- Twenty official Need-to-Know subject categories, from Statutes and Rules through Math Problems (incl. Permits, Design Criteria, Safety, Laboratory, Collection, Pumping, treatment stages, Process Control, Disinfection, Sludge Digestion, Biosolids, Effluent Disposal).
- Source: TCEQ Wastewater Operator Exam Knowledge ('What You Need to Know for a Class D Wastewater Treatment Plant Operator Exam' table.)
Last reviewed 2026-08-01. Facts link to their official source.