SWAT+Toolbox calibration

[Rodiah _]

Hello, please help me with parameter calibration in the SWAT+ Toolbox.

I would like to ask about an issue I’m facing while working on a SWAT+ model for the ANCAR watershed in Mataram City. I obtained an NSE value of -2.30 and an R² of 0.17. The simulation results are below the observed values.

What factors are causing my NSE to be far from acceptable? Also, do you have any suggestions for suitable calibration parameters for the Ancar River Basin, which is located in the middle of an urban area where a significant amount of water is undoubtedly being diverted for irrigation or similar purposes?

regards,

diah