Part of the water operator pass
California D2 practice exam: the full 100-question exam
100 questions · 180 minutes
100 questions in the official content counts. You get a score by category and topic, and an explanation for every option.
Before you start
- Every question has four options and one best answer.
- Content: Disinfection 20, Distribution System Design / Hydraulics 20, Equipment Operation / Maintenance / Inspections 20, Drinking Water Regulations / Management / Safety 10, Water Mains and Piping 20, Water Quality / Water Source 10.
- The Board publishes the category counts but not a time limit or passing score; our clock is 3 hours.
- You can skip, go back, change answers and flag questions. The 180-minute clock keeps running in background tabs and reloads, and the exam is submitted when time runs out.
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.