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RSMSSB JE Civil Diploma Oct 2016 Official Paper

Option 4 : 1000 hectares per cum/s

The relation between Duty (D) in ha/cumecs , Delta in meter and Base period (B) in days is given by the following relation:

\(D = \frac{{8.64\;B}}{\Delta }\)

D = \(\frac{{8.64\; \times \;10}}{{8.64\; \times \;{{10}^{ - 2}}}}\)

**∴ Hence, Duty = 1000 ha/cumecs**

__Important point: __

Duty means how much area can be irrigated by canal discharging one m^{3}/s water. For Ex. Duty of 10 ha/cumecs means 1 cumecs discharge can irrigate 10 hectare area.