At Grade 3 the largest block is Operations and Maintenance (21% of the exam).
For the crews who keep the sewer system flowing before anything reaches the plant: cleaning, inspection, root and grease control, spill response, and lift stations.
Start studying Grade 3| Content area | % of the exam | |
|---|---|---|
| Operations and Maintenance | 21 | |
| Tools and Equipment | 16 | |
| Plans, Maps and As-Builts | 13 | |
| Safety and Regulations | 21 | |
| Administration | 17 | |
| Math | 12 |
Administration: crew planning · an original practice item written only from publicly available sources, not a real exam question
Your agency wants 40% of its 180 miles of gravity sewer cleaned each year. A hydro-flush crew averages 1,200 ft a day over 220 working days. How many full crews must you staff?
C. 2 crews
Target = 0.40 × 180 mi = 72 mi × 5,280 = 380,160 ft a year. One crew covers 1,200 × 220 = 264,000 ft a year, so 380,160 ÷ 264,000 = 1.44 crews, which rounds up to 2 full crews. 1.44 is the unrounded ratio, which cannot be staffed; 1 rounds down and leaves the goal unmet; 72 is the mileage, not a crew count.
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Topic coverage follows Collection System Maintenance Candidate Handbook, Version 2025.01 (California Water Environment Association, effective May 2025). Practice questions are written only from publicly available sources (that outline and the regulations and references it cites); they are not real exam questions, which are confidential. Check current application requirements, fees and exam dates on the certifying body's own page: official certification page.
Questions, flashcards, and explanations are AI-written from publicly available sources only: the exam content outlines and candidate materials each certifying body publishes without restriction, and the regulations and technical references they cite. No confidential material is used, including actual exam questions, recollections of any exam sat by the author, or any handbook or document released under a confidentiality agreement. Content is then put through repeated review — regulatory values checked against primary sources, every calculation recomputed, and errors corrected — plus spot checks by the author, who holds California water operator certifications and a California civil engineering licence. Those spot checks are sampling, not a professional review: nothing here is stamped, sealed, or offered as engineering advice, and not every item has been individually verified, so mistakes can still slip through.