Compute the total depth of water for wheat crop if the duty at field is 700 ha/cumec and the base period is 360days.

Question

Question

This question was previously asked in

HPCL Engineer (Civil) 04 Nov 2022 Official Paper

Answer 1

Concept:

The relation between Duty, Delta and Base period are as follows:

\({\rm{Δ }} = \dfrac{{8.64\:\times \:B}}{D}\;m\)

\(\rm{}Δ = \dfrac{{Base\;Period \times Depth\;of\;Watering}}{{Interval\;of\;Watering}}\)

Δ → depth of water required (m), D → Duty (hectares per cumec)

B → Base period (days)

Calculation:

Given,

Duty = 700 ha/cume

Base Period = 120 days

From the equation

\({\rm{Δ }} = \dfrac{{8.64\:\times \:360}}{700}\;m\) = 4.44 m