online_rational_composite:   Peak discharge for a composite catchment using the rational method
INPUT DATA:     [Description]     [Example]

Select:   

Drainage area Aa :   

Runoff coefficient Ca :    

Time of concentration tca :    
  min

Drainage area Ab :    

Runoff coefficient Cb :    

Time of concentration tcb :    
  min

Return period T :    
  yr

OUTPUT:

Qp  =  I  ∑ (C A)

Peak discharge Qp :     

Design rainfall duration trd :     

IDF Formula:

       k T n
I  =  _______________
       (tr  +  b)m
Coefficient k :  

[Leave blank to set default k = 1000]

Exponent n :  

[Leave blank to set default n = 0.2]

Coefficient b :  

[Leave blank to set default b = 20]

Exponent m :  

[Leave blank to set default m = 0.7]

            

  Your request was processed at  12:31:43 am on July 2nd, 2025   [ 250702  00:31:43 ]    [140403]