Channel Parameters Sensitivity

I have develop a event based model to analyze the sensitivity of the channel parameters (Bed and Bank Roughness coefficient, Bed width, Maximum Depth) and the sensitivity of the intermittent storage areas. According to the results, sensitivity values are lesser than 10%.  I mean when I change the channel parameters one at a time, plus 50% or minus 50%, model outflow hydrograph peak and the hydrograph shape variation is less than 10%. I used daily resolution rainfall data series. I want to know why there is no significant change when I change those parameters.


I have attached the model files here.

Thank you

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  • Thank you very much Bob

  • Hello, Regarding the maximum depth, the depths during the simulation seem to peak at less than 0.10 meters which is much less than the maximum depth so changing the maximum depth will do little to change the channel flow.  The small depth also means the width is not changing much in the trapezoidal channels.  There is a non linear relationship between n and depth so changing the n by 50 percent wil not change the depth by 50 percent.     

    You are also using the KW solution, if you use the DW solution you might find more sensitivity.

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