LARE Irrigation Design Flashcards

What does 'matched precipitation rate' (MPR) technology accomplish in an irrigation zone?

Answer: It ensures that quarter-, half-, and full-circle heads in the same zone all apply water at the same rate

MPR technology ensures heads with different arc sizes apply water at the same depth per hour so the entire zone receives uniform coverage without wet or dry spots.

What is the function of a pressure-compensating emitter in a drip irrigation system?

Answer: It maintains a consistent flow rate across a wide range of operating pressures

Pressure-compensating emitters maintain a consistent output flow rate despite variations in operating pressure, ensuring uniform application on slopes or long lateral runs.

What term describes the combined water loss from soil evaporation and plant transpiration?

Answer: Evapotranspiration (ET)

Evapotranspiration (ET) combines evaporation from soil and transpiration through plant tissue, representing the total water demand that irrigation must replace.

What is the purpose of a check valve built into rotor and spray heads?

Answer: To prevent low-head drainage after the zone valve closes on sloped sites

Check valves in heads prevent low-head drainage, where water drains out of the lowest heads in a zone after the valve closes, wasting water and causing puddles or erosion.

Which irrigation method is generally the most water-efficient for trees and shrubs in a landscape?

Answer: Subsurface drip irrigation

Subsurface drip irrigation delivers water directly to the root zone with minimal evaporation or runoff losses, making it the most efficient delivery method for woody plants.

What does 'distribution uniformity' (DU) measure in an irrigation system?

Answer: How evenly water is applied across all parts of an irrigated area

Distribution uniformity quantifies how evenly water is distributed across an irrigated area; a higher DU means more consistent coverage and less over- or under-watering of any given spot.

In irrigation design, what is 'hydrozoning'?

Answer: Grouping plants with similar water requirements into the same irrigation zone

Hydrozoning groups plants with similar water needs—high, moderate, or low/drought-tolerant—into a single irrigation zone so water can be applied at the rate appropriate for that plant community.