2.6. Duty and Delta

Duty

Duty may be defined as the number of hectares of land irrigated for full growth of a crop by the supply of 1 m³/s of water during the entire base period of that crop.

It is denoted by D

Unit of duty is hectares/cumec.

Delta

Delta is the total depth of water required by a crop during the entire period of the crop in the field.

It is denoted by Δ.

Unit of delta is cm or m.