Question

For a 4 hr UH of catchment of $300k{m}^2$ having following ordinates
$\begin{array}{cccccccccccccccccccccc}\text{Time}& & & & & & & & & & & & & & & & & & & & & \\ \left(\text{hr}\right)& 1& 2& 3& 4& 5& 6& 7& 8& 9& 10& 11& 12& 13& 14& 15& 16& 17& 18& 19& 20& 21\\ \text{UH}& & & & & & & & & & & & & & & & & & & & & \\ \text{ordinate}& 0& 6& 36& 66& 91& 106& 93& 79& 68& 59& 49& 41& 34& 27& 23& 17& 13& 9& 6& 3& 0\\ \left(m^3/s\right)& & & & & & & & & & & & & & & & & & & & & \end{array}$

The peak ordinate of S-curve will be

• A. $158m^3/s$
• B. $208m^3/s$
• C. $175m^3/s$
• D. $134m^3/s$

Answer 1

The correct option is B $208m^3/s$

$A=300k{m}^2$

$Q=\frac{2.78A}{t_1}=\frac{2.78\times 300}{4}=208m^3/s$