Irrigation and Water Management Flashcards

What is a rain sensor required to do on new irrigation systems in many US states?

Answer: Automatically shut off the system during or after rain

Many US states mandate rain sensors that interrupt irrigation cycles when rainfall occurs, preventing wasteful watering during or immediately after rain events.

What is the primary disadvantage of irrigating turfgrass in the evening compared to early morning?

Answer: Foliage stays wet overnight, promoting fungal disease

Evening irrigation leaves foliage wet for many hours in the absence of solar drying, creating ideal conditions for fungal pathogens like brown patch and dollar spot.

What is static water pressure and why is it important in irrigation design?

Answer: Water pressure when no flow is occurring; determines system capacity and head selection

Static pressure is the water pressure measured when no water is flowing; it is the starting point for calculating working pressure and selecting appropriate sprinkler heads.

What does gallons per minute (GPM) measure in irrigation system design?

Answer: The flow rate of water through the system or individual heads

GPM measures the flow rate of water delivered by a sprinkler head, zone, or main line, which is critical for sizing pipes, valves, and avoiding overloading the water meter.

Which irrigation method is specifically recommended for slopes to minimize runoff?

Answer: Drip irrigation with low-flow emitters

Low-flow drip irrigation applies water slowly enough for sloped soil to absorb it without generating surface runoff.

What is the purpose of a pressure-compensating drip emitter?

Answer: Deliver a consistent flow rate despite pressure variations in the line

Pressure-compensating emitters maintain a constant flow rate across a wide range of inlet pressures, ensuring uniform distribution even on slopes or long runs.