North Carolina (NC) Irrigation Contractor Examinations — Level I & II
North Carolina Irrigation Contractor Exam – Level I & II
200 Practice Questions with Answers and Rationales
Welcome to this comprehensive practice question bank for the North Carolina
Irrigation Contractor Licensing Exam (Levels I and II). These questions are based
on the official exam content outline from the NC Irrigation Contractors' Licensing
Board (NCICLB) and cover all three exam sections: Water Efficiency/Conservation,
Irrigation Contracting/Construction, and Basic Business Skills.
Exam Structure at a Glance:
Section Number of Questions Passing Score
Water Efficiency/Conservation ~50 70%
Irrigation Contracting/Construction ~60 70%
Basic Business Skills ~40 70%
Section 1: Water Efficiency & Conservation (Questions 1-50)
1. A homeowner requests an irrigation system for a 0.5-acre lot with clay soil. The
sprinkler heads you select have a precipitation rate higher than the soil's
infiltration rate. What is the most likely consequence?
A) Deep percolation beyond root zone
,B) Surface runoff and ponding
C) Even water distribution
D) Reduced evaporation losses
Answer: B) Surface runoff and ponding
Rationale: When the precipitation rate exceeds the soil's infiltration rate, water
cannot enter the soil fast enough, resulting in surface runoff and ponding. Clay
soils have particularly slow infiltration rates, making this a common issue.
2. You are calculating the precipitation rate for a zone with four quarter-circle
rotors, each discharging 2.0 GPM, spaced 40 feet apart in a square pattern. What
is the precipitation rate in inches per hour?
A) 0.48 inches/hour
B) 0.96 inches/hour
,C) 1.20 inches/hour
D) 1.44 inches/hour
Answer: A) 0.48 inches/hour
Rationale: Precipitation Rate = (96.25 × Total GPM) ÷ Area. Area = 40 ft × 40 ft =
1,600 sq ft. Total GPM = 4 heads × 2.0 GPM = 8 GPM. (96.25 × 8) = 770; 770 ÷
1,600 = 0.48 inches/hour.
3. The primary factor that determines a plant's water requirement is:
A) Soil texture only
B) Ambient temperature only
C) Evapotranspiration (ET)
D) Wind speed only
, Answer: C) Evapotranspiration (ET)
Rationale: ET combines water loss from both soil evaporation and plant
transpiration, making it the key driver of irrigation scheduling. It is influenced by
temperature, humidity, wind, and solar radiation.
4. Which soil characteristic most directly influences the infiltration rate?
A) Bulk density
B) Organic matter content
C) Particle size distribution
D) Soil pH
Answer: C) Particle size distribution
North Carolina Irrigation Contractor Exam – Level I & II
200 Practice Questions with Answers and Rationales
Welcome to this comprehensive practice question bank for the North Carolina
Irrigation Contractor Licensing Exam (Levels I and II). These questions are based
on the official exam content outline from the NC Irrigation Contractors' Licensing
Board (NCICLB) and cover all three exam sections: Water Efficiency/Conservation,
Irrigation Contracting/Construction, and Basic Business Skills.
Exam Structure at a Glance:
Section Number of Questions Passing Score
Water Efficiency/Conservation ~50 70%
Irrigation Contracting/Construction ~60 70%
Basic Business Skills ~40 70%
Section 1: Water Efficiency & Conservation (Questions 1-50)
1. A homeowner requests an irrigation system for a 0.5-acre lot with clay soil. The
sprinkler heads you select have a precipitation rate higher than the soil's
infiltration rate. What is the most likely consequence?
A) Deep percolation beyond root zone
,B) Surface runoff and ponding
C) Even water distribution
D) Reduced evaporation losses
Answer: B) Surface runoff and ponding
Rationale: When the precipitation rate exceeds the soil's infiltration rate, water
cannot enter the soil fast enough, resulting in surface runoff and ponding. Clay
soils have particularly slow infiltration rates, making this a common issue.
2. You are calculating the precipitation rate for a zone with four quarter-circle
rotors, each discharging 2.0 GPM, spaced 40 feet apart in a square pattern. What
is the precipitation rate in inches per hour?
A) 0.48 inches/hour
B) 0.96 inches/hour
,C) 1.20 inches/hour
D) 1.44 inches/hour
Answer: A) 0.48 inches/hour
Rationale: Precipitation Rate = (96.25 × Total GPM) ÷ Area. Area = 40 ft × 40 ft =
1,600 sq ft. Total GPM = 4 heads × 2.0 GPM = 8 GPM. (96.25 × 8) = 770; 770 ÷
1,600 = 0.48 inches/hour.
3. The primary factor that determines a plant's water requirement is:
A) Soil texture only
B) Ambient temperature only
C) Evapotranspiration (ET)
D) Wind speed only
, Answer: C) Evapotranspiration (ET)
Rationale: ET combines water loss from both soil evaporation and plant
transpiration, making it the key driver of irrigation scheduling. It is influenced by
temperature, humidity, wind, and solar radiation.
4. Which soil characteristic most directly influences the infiltration rate?
A) Bulk density
B) Organic matter content
C) Particle size distribution
D) Soil pH
Answer: C) Particle size distribution
