Fixed Grid Irrigation Systems

Name:

Date:

WALT (We Are Learning To)

WALT: Understand the purpose, components and uses of fixed grid (solid set) irrigation systems and make simple design and maintenance decisions.

Success criteria:

- I can describe what a fixed grid irrigation system is and where it is used.

- I can list key components and two maintenance tasks.

- I can estimate sprinkler numbers for a rectangular area using grid spacing.

Differentiation strategies: Provide a labelled diagram for students who need visual support; give sentence starters for written answers; allow pair discussion before answers for students who benefit from oral processing.

Extension activities: Research an irrigation controller that supports "little and often" scheduling and write a one-paragraph recommendation. Compare water-use efficiency figures.

Dyslexia-friendly reading options: Read text aloud with a partner, highlight key words (sprinkler, grid, frost protection, little and often), and use a coloured overlay if helpful.

Questions

1. What is a fixed grid (solid set) irrigation system?

A mobile machine that moves across the paddock (centre pivot)

Permanently mounted sprinklers on fixed supports in a grid pattern

Hand-held sprinklers used by contractors

2. Which situations make fixed grid systems a good choice? (choose the single best answer)

Large flat paddocks best for centre pivots

Irregular-shaped fields, undulating terrain and frost protection

Urban lawns only

3. Tick all advantages of fixed grid systems:

Good for frost protection

Requires no maintenance ever

Enables "little and often" scheduling

Easily moved every season without effort

4. Explain in one or two sentences what "little and often" scheduling means for irrigation.

5. List two main components of a solid set irrigation system.

6. Calculation: A rectangular paddock is 90 m by 60 m. Sprinklers are placed on a square grid with 15 m spacing (rows and columns 15 m apart). How many sprinklers are needed? Show working.

7. Name two routine maintenance tasks you would schedule each season to keep a fixed grid system working well.

8. Sketch a simple plan showing sprinkler placement for a small undulating field (include direction of slope). Label one feature that helps prevent uneven watering.

9. Extension: Suggest one modification to the system to reduce water loss and one simple measurement you would take to assess system efficiency.