4. Estimation of Design Discharge

Try these first

1. 1.

   Define Duty in terms of irrigation.

   Hint

   Think about how much land you can irrigate with one unit of water.

2. 2.

   What does Delta measure?

   Hint

   Consider how deep the water needs to be for the crops to grow.

3. 3.

   What does the term 'Design Discharge' refer to?

   • A natural flow rate
   • Maximum flow designed for a canal
   • Average flow rate

   Hint

   Think about what it means to design a water system for maximum use.

4. 4.

   True or False: The duty is a measure of how much area can be irrigated per unit discharge.

   • True
   • False

   Hint

   Consider the definition of duty you’ve learned.

5. 5.

   A field has a crop with a water depth requirement (Δ) of 0.6 meters and irrigation is to occur over 20 days. Calculate the duty (D) if the total area to be irrigated is 15 hectares.

   Hint

   Break the calculations step by step.

6. 6.

   A canal system needs to estimate its output using historical project data, which indicates a typical duty of 100 hectares per cumec. If a farmer wants to irrigate 25 hectares, how much discharge does he need?

   Hint

   Think about the conversion factor and how duty works.