Water Distribution Prep Class (Grades 1-3)

Introduction

• Focus on system layout, valves, meters, hydrants, and backflows.
• Study tactics:
  • Create a conducive study environment.
  • Understand rather than memorize.
  • Summarize in your own words.
  • Utilize flashcards.
  • Avoid procrastination.
  • Aim for high goals (100% on tests).
  • Continuous education and certifications.

Study Resources

• Water Distribution Operator Book (AWWA).
• Certification exam prep books (especially for math).
• Sacramento State Water Program.
• WaterWise Pro app and in-house training.
• California State Water Board for regulations and exam prep.

Public Water Systems

• Community Public Water System: 15+ service connections or serves 25+ persons for over 60 days/year.
• Non-Transient Non-Community: Serves 25+ people regularly for over six months (e.g., schools, factories).
• Transient Non-Community: Serves 25 persons/day occasionally (e.g., rest stops).

Water Distribution System Layouts

• Arterial Loop System: Large diameter main around the area, ensures flow from four directions.
• Grid System: Interconnected mains with larger arterial mains.
• Tree System: Mains branch with many dead ends, poor design.

Water System Valves

• Gate Valves: Used to start/stop flow, not for prolonged throttling.
  • Rising Stem (OS&Y) and Non-Rising Stem.
• Butterfly Valves: Disc rotates to open/close, used for on-off service.
• Check Valves: Allow flow in one direction, prevent backflow when the pump shuts down.
• Pressure Regulating & Relief Valves: Maintain set pressure, protect against high pressure.
• Altitude Valves: Control reservoir fill based on pressure settings.
• Air & Vacuum Relief Valves: Vent air and prevent vacuum in mains.

Water Meters

• Essential for revenue and measuring customer usage.
• Types of meters:
  • Positive Displacement Meters: Low flow rates, mutating disc, and piston type.
  • Velocity Type Meters: Multi-jet and turbine.
  • Compound Meters: Measure high and low flow rates.
  • Magnetic and Ultrasonic Meters: Highly accurate, used for modern infrastructure.
  • Pressure Differential Meters: Venturi and orifice plate types.

Fire Hydrants

• Inspect annually, install 350-600 feet apart, maintain a minimum of 20 PSI.
• Types:
  • Dry Barrel: Used in freezing areas, no water discharge upon damage.
  • Wet Barrel: Filled with water, separate valve for each nozzle.

Cross Connection & Backflows

• Backflow: Foreign substances enter potable water.
  • Causes: Back pressure and back siphonage.
• Backflow Devices:
  • Air Gap: Most effective, physical separation.
  • Reduced Pressure Zone (RPZ): Two check valves with relief valve, used in high-risk areas.
  • Double Check Valve: Similar to RPZ but no relief valve.
  • Vacuum Breaker: Atmospheric and pressure types, used in irrigation.

Additional Information

• Continuous updates to study materials.
• Importance of feedback from recent test-takers.
• Encourage sharing experiences to improve communal study resources.