TEXAS IRRIGATOR LICENSE FINAL PAPER
2026 COMPREHENSIVE QUESTIONS AND
ACCURATE SOLUTIONS
◉ C-Factor
Answer: Rating of the smoothness of the inside of the pipe.
Higher C-factor = smoother
PVC is 150. Copper is 140.
Generally decreases over time meaning the pipe gets rougher and
more friction loss.
◉ Densogram
Answer: Graphic view of precipitation to check uniformity.
Higher rates are darker.
◉ Distribution Uniformity (DU)
, Answer: Uniformity of distribution of water over a given area as a %.
Found by doing a catch can test.
Closer to 100% is better with 75%-80% excellent, 65%-75% good
and <65% poor.
◉ Dynamic Water
Answer: Water in motion
◉ Dynamic Pressure (Working Pressure)
Answer: Pressure of water in motion.
Pressure left wehn all pressure losses are subtracted from static
pressure.
◉ Elevation Gain & Loss
Answer: Pressure gain or loss of 0.433 psi for each 1' of elevation.
◉ Flow
Answer: Movement of water in pipes. Measured as gpm (gallons per
minute).
2026 COMPREHENSIVE QUESTIONS AND
ACCURATE SOLUTIONS
◉ C-Factor
Answer: Rating of the smoothness of the inside of the pipe.
Higher C-factor = smoother
PVC is 150. Copper is 140.
Generally decreases over time meaning the pipe gets rougher and
more friction loss.
◉ Densogram
Answer: Graphic view of precipitation to check uniformity.
Higher rates are darker.
◉ Distribution Uniformity (DU)
, Answer: Uniformity of distribution of water over a given area as a %.
Found by doing a catch can test.
Closer to 100% is better with 75%-80% excellent, 65%-75% good
and <65% poor.
◉ Dynamic Water
Answer: Water in motion
◉ Dynamic Pressure (Working Pressure)
Answer: Pressure of water in motion.
Pressure left wehn all pressure losses are subtracted from static
pressure.
◉ Elevation Gain & Loss
Answer: Pressure gain or loss of 0.433 psi for each 1' of elevation.
◉ Flow
Answer: Movement of water in pipes. Measured as gpm (gallons per
minute).
