Wastewater Collection Class II Practice Test (ABC/WPI)

Original Class II questions written to WPI’s 2025 Need-to-Know Criteria, every option explained.

Free sample · Question 1 of 5Pumps and equipment

What does a totalizer on a flow meter show?

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178 original Wastewater Collection Class II questions with explanations · 100-question practice exam · 5 parts

Wastewater Collection Class II exam format

Water Professionals International (WPI, formerly the Association of Boards of Certification, ABC) writes the standardized wastewater collection operator exams that many state certification programs use. The 2025 Class II exam has 100 scored questions in 5 content areas; 10% are calculations. Your state sets eligibility, fees, the time limit and the passing score.

Questions
100 scored, plus up to 10 unscored pretest questions mixed in
Content (2025 Need-to-Know)
Equipment Operation, Evaluation, and Maintenance 25, Collection System Operation, Maintenance, and Restoration 25, Lift Station Operation and Maintenance 18, Collection System Monitoring, Evaluation, and Adjustment 16, Security, Safety, and Administrative Procedures 16
Calculations
10% of the exam; WPI provides its Formula/Conversion Table, and items give US and metric units
Rules of the exam
Closed book. Bring photo ID and a non-programmable calculator
Time, fee and passing score
Set by your state certification program, not by WPI
Results
Reported by your certifying authority; WPI does not give results to candidates
Language
The 2025 Class I and II exams are also available in Spanish
Which version
This page follows the 2025 standardized exam. Some programs still use older editions or custom exams; ask your certifying authority
Line drawing of a sewer cutaway under a street: two manholes with steps, a sloping gravity sewer between them, a house lateral and a lift station control cabinet on the sidewalk

What’s on the Wastewater Collection Class II exam

The content areas and question counts below are the exam owner’s. Our practice exam uses the same counts; each row links to the free topic drills that practice it.

Content areaWhat it coversQuestions (official)Drill
Equipment Operation, Evaluation, and MaintenanceCleaning, inspection and pumping equipment25Cleaning and inspection drillPumps and equipment drill
Collection System Operation, Maintenance, and RestorationSewers, manholes, stoppages, construction and rehabilitation25Collection maintenance drill
Lift Station Operation and MaintenanceWet wells, pumps, controls, alarms and force mains18Lift stations drill
Collection System Monitoring, Evaluation, and AdjustmentFlow monitoring, I/I, overflows, odors and industrial users16I/I and overflows drillPumps and equipment drill
Security, Safety, and Administrative ProceduresSafety, records and regulations16Safety drillManagement drillPermits and rules drill

How to take the Wastewater Collection Class II exam

  1. Check with your state certifying authority that it uses the WPI standardized exam and which edition.
  2. Meet your state’s education and experience rules and apply to the state program.
  3. Study the content areas in WPI’s Need-to-Know Criteria and the formula table.
  4. Sit the exam under your state’s rules; your state reports your result.

Common questions

How many questions are on the Wastewater Collection Class II exam?

100 scored questions plus up to 10 unscored pretest questions. WPI's 2025 Need-to-Know Criteria split them: Equipment Operation, Evaluation, and Maintenance 25, Collection System Operation, Maintenance, and Restoration 25, Lift Station Operation and Maintenance 18, Collection System Monitoring, Evaluation, and Adjustment 16, Security, Safety, and Administrative Procedures 16.

What is the passing score?

WPI does not set one for candidates; each state certification program sets its passing score, time limit and fees. Our practice exam shows your score in each content area.

Is ABC the same as WPI?

Yes. The Association of Boards of Certification (ABC) is now Water Professionals International (WPI), and ABC Testing is its testing service.

Do I get a formula sheet?

Yes. WPI provides its Formula/Conversion Table with the exam. 10% of the Class II questions are calculations.

Are these real WPI questions?

No. WPI exam questions are copyrighted and confidential. These are original practice questions written to the published Need-to-Know Criteria, with an explanation for every option.

Ready for exam day?

100 questions in the official content counts, with a score for every area and an explanation for every option.

Or start with a free ten-question drill

More ABC/WPI exam practice

One water operator pass covers every practice exam on the site.

Content-area counts and exam rules checked November 2026 on gowpi.org (2025 Need-to-Know Criteria): WPI: 2025 Need-to-Know Criteria · WPI Wastewater Collection Operator Class II Need-to-Know Criteria (PDF) · WPI: Information for examinees.

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.