Exam Questions And Correct Answers

CA D82 Drip Irrigation Contractor Exam Questions And Correct Answers (Verified Answers) Plus Rationale2026 Q&A| Instant Download Pdf

• Which component is primarily responsible for controlling water flow in

a drip irrigation system?

• Filter
• Mainline
• Pressure regulator
• Drip emitter

Rationale: The pressure regulator ensures water is delivered at a

consistent pressure suitable for drip emitters, preventing over- or under-watering.

• What is the typical operating pressure range for most drip irrigation

systems?

• 5–10 psi
• 10–15 psi
• 15–30 psi
• 30–50 psi

Rationale: Drip systems are designed to operate efficiently at low

pressures, typically between 15–30 psi, to ensure uniform water distribution.

• What is the main purpose of a filter in a drip irrigation system?
• Reduce water pressure
• Prevent soil erosion
• Remove particles and debris
• Increase water flow

Rationale: Filters prevent clogging of emitters by removing sediments

and debris from the water supply. 1 / 3

• Which type of drip emitter delivers a uniform amount of water

regardless of pressure fluctuations?

• Turbulent emitter
• Pressure-compensating emitter
• Non-compensating emitter
• Adjustable emitter

Rationale: Pressure-compensating emitters maintain consistent flow

even with pressure variations, ensuring uniform irrigation.

• How should drip tubing be spaced in a row crop to achieve efficient

coverage?

• 5–10 feet apart
• 12–24 inches apart
• 3–4 feet apart
• 6–8 feet apart

Rationale: Emitter spacing and tubing placement depend on crop type

and root zone; most row crops are efficiently irrigated with 12–24 inch spacing.

• Which soil type typically requires closer emitter spacing?
• Sandy soil
• Loamy soil
• Clay soil
• Gravel

Rationale: Clay soils have lower infiltration rates and higher water

retention, requiring closer emitter spacing for even distribution.

• What is the most common cause of emitter clogging?
• Low water pressure
• Sediment buildup
• Excessive fertilizer
• Incorrect tubing

Rationale: Sediment and particulate matter in water are the primary

cause of emitter clogging; proper filtration is essential.

• Which water source requires pre-filtration before using in drip

irrigation?

• Municipal water
• Surface water from ponds or rivers
• Rainwater
• Bottled water 2 / 3

Rationale: Surface water contains sediments, algae, and debris that

can clog emitters; pre-filtration is necessary.

• How often should a drip irrigation system be flushed?
• Every day
• Once a month
• Every six months
• Once a year

Rationale: Periodic flushing removes accumulated debris from

mainlines and lateral lines, reducing clogging risk.

• What is the primary purpose of a backflow preventer in a drip

system?

• Regulate pressure
• Prevent contamination of potable water
• Filter sediments
• Increase flow

Rationale: Backflow preventers protect the main water supply from

contamination due to reverse flow from the irrigation system.

• Which material is most commonly used for drip tubing?

A. PVC

• Copper
• Polyethylene (PE)
• Galvanized steel

Rationale: Flexible polyethylene tubing is widely used for drip systems

because it is durable, UV-resistant, and easy to install.

• What is the recommended maximum emitter flow rate for most

landscape applications?

• 0.1–0.2 gph
• 0.5–1 gph
• 0.5–2 gph
• 2–5 gph

Rationale: Typical drip emitters release 0.5–2 gallons per hour,

allowing slow, deep watering without runoff.

• What is the function of a manifold in a drip irrigation system?
• Increase water pressure
• Distribute water evenly to multiple lines
• Filter debris
• Adjust flow rate
• / 3