CFB CFB Drainage & Irrigation Systems 2 — Questions and Answers
Question 1: What type of irrigation head is most commonly used on natural grass athletic fields for its uniform coverage pattern?
- Drip emitters
- Pop-up rotary heads (Correct answer)
- Fixed spray heads
- Micro-bubblers
Correct answer: Pop-up rotary heads
Pop-up rotary heads are preferred for athletic fields because they provide uniform coverage over large areas while remaining flush with the surface when not in use.
Question 2: Which backflow prevention device is typically required by US plumbing codes for athletic field irrigation systems connected to a potable water supply?
- Gate valve
- Pressure vacuum breaker (PVB) (Correct answer)
- Ball valve
- Check valve
Correct answer: Pressure vacuum breaker (PVB)
A pressure vacuum breaker (PVB) is commonly required by US codes to prevent contaminated irrigation water from flowing back into potable water supplies.
Question 3: What does 'ET-based' irrigation scheduling mean in the context of athletic field management?
- Scheduling irrigation based on equipment testing intervals
- Applying water to replace the amount lost through evapotranspiration (Correct answer)
- Using electronic timers to automate irrigation cycles
- Estimating turf stress through thermal imaging
Correct answer: Applying water to replace the amount lost through evapotranspiration
ET-based scheduling replaces only the water lost through evapotranspiration, matching irrigation input to actual plant water use for efficiency.
Question 4: In a catch-can test for an athletic field irrigation system, what is the acceptable coefficient of uniformity (CU) for a well-designed system?
- Above 50%
- Above 65%
- Above 75%
- Above 85% (Correct answer)
Correct answer: Above 85%
A coefficient of uniformity above 85% is considered acceptable for a well-designed and functioning athletic field irrigation system.
Question 5: What is the primary purpose of check valves installed within pop-up irrigation heads on sloped athletic fields?
- To regulate operating pressure at the head
- To prevent low-head drainage after irrigation cycles (Correct answer)
- To filter debris from entering the nozzle
- To allow flow adjustment without digging up the head
Correct answer: To prevent low-head drainage after irrigation cycles
Check valves in irrigation heads on sloped fields prevent water from draining out of lower-elevation heads after the system shuts off, avoiding puddling and wasted water.
Question 6: Which soil amendment is most commonly added to improve drainage in a native-soil athletic field construction project?
- Peat moss
- Calcined clay
- Coarse sand (Correct answer)
- Vermiculite
Correct answer: Coarse sand
Coarse sand is most commonly incorporated into native soil profiles to increase porosity and improve drainage on athletic fields.
CFB CFB Drainage & Irrigation Systems 2
What type of irrigation head is most commonly used on natural grass athletic fields for its uniform coverage pattern?