# How to Calculate Discharge of The Water If The Depth & Crop Period are Given

## How to Calculate Discharge of The Water If The Depth & Crop Period are Given

Mathematical Problem

A Waterhouse has a culturable commanded area of 2200 hectares. The intensity of irrigation for crop A is 50% and for B is 35%, both the crops being Rabi crops. Crop A and B have a crop period of 25 days and 20 days respectively. Calculate the discharge of the water if the depth for crops A and B is 12 cm and 18 cm respectively.

Solution:

Culturable land for irrigation = 2200 hectares.

Area of irrigation for Crop A = 2200 × 50% = (2200 × 50)/100 = 1100 hectares.

Area of irrigation for Crop B = 2200 × 35% = (2200 × 35)/100 = 770 hectares.

Using the relation.

D = (8.64 × B)/ ∇

Discharge for crop A

Here,

• ∇ = 12 cm = 0.12 m.
• B = 25 days

Duty (D) = (8.64 × 25)/0.12 = 1800 hectares/cumec.

Required discharge for crop A = (1100/1800) = 0.61 cumec.

Discharge for crop B

Here,

• ∇ = 18 cm = 0.18 m
• B = 20 days

Duty (D) = (8.64 × 20)/0.18 = 960 hectares/cumec.

Required discharge for crop B = ( 770/960) = 0.80 cumec.

S0, the total discharge of water course = (0.61 + 0.80) = 1.41 cumec.