Question

A 12-hour unit hydrograph (of 1 cm excess rainfall) of a catchment is of a triangular shape with a base width of 144 hour and a peak discharge of 23 m\(^3\)/s. The area of the catchment (in km\(^2\), round off to the nearest integer) is \(\underline{\hspace{2cm}}\).

Hint:

The area of the catchment can be found using the peak discharge and base width of the triangular unit hydrograph.

Answer 1

Correct Answer: 595 - 598

The area of the catchment can be calculated using the formula for the triangular unit hydrograph, which is given by: \[ \text{Area of catchment} = \frac{\text{Peak discharge} \times \text{Base width}}{\text{Rainfall excess}}. \] Substituting the given values: \[ \text{Area of catchment} = \frac{23 \, \text{m}^3/\text{s} \times 144 \, \text{hours}}{1 \, \text{cm}} = 595.2 \, \text{km}^2. \] Thus, the area of the catchment is \( \boxed{595} \, \text{km}^2 \).