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How do canals carry irrigation water from reservoirs to farms?

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Large wheeled irrigation sprinkler sprays water over green crops in a field, with mountains and cloudy sky in the background. — Irrigation Specialized irrigation equipment watering crops in a field.

Canals serve as essential transport systems for moving water from reservoirs to agricultural areas, particularly when the water source is distant from the point of use. These systems primarily rely on gravity flow to move water, though pumping may be used to supplement the process when necessary.1

The distribution network typically follows a hierarchical structure:
* Mains: Water is first transported from the reservoir through large primary canals.1
* Branches and Laterals: From the mains, the water flows into smaller branches or laterals.1
* Distributors: Finally, the water reaches distributors that serve specific groups of farms.1

To ensure efficiency and structural integrity, canals are often lined with concrete to prevent seepage losses, control weed growth, and reduce erosion. The construction process frequently involves excavating the canal to a precise cross section and applying concrete to the bottom and sides. Additionally, these systems incorporate auxiliary structures such as weirs (flow-diversion dams) and sluices to regulate and manage the flow of water effectively.1