Pipe Sizing: Which factors are typically considered when sizing irrigation pipe?

• A. Pipe color and brand
• B. Desired flow rate, allowable friction loss, and velocity
• C. Soil texture only
• D. Controller model

Answer: (B)

Sizing irrigation pipe is about carrying the required water to all zones while keeping pressure losses and water velocity within practical limits. The key considerations are the desired flow rate for the system (the total water needed by all zones), the allowable friction loss along the longest runs and through fittings, and the velocity of the water inside the pipe (which should stay within a range that minimizes noise, erosion, and potential water hammer). These factors determine the appropriate pipe diameter and material to use. Pipe color and brand don’t affect hydraulics, soil texture mainly influences installation conditions rather than sizing, and controller model doesn’t change the pipe’s ability to carry the required flow.