Requesting help

[Grmay Kassa Brhane]

Dear all SWAT+ users, I am working on SWAT+ modeling for groundwater estimation purposes, and I failled to have good fitting of the simualted and observed river , and the Pbias and NSE are very bad  flow as follows  . could any one of you can help me to concepually and technical issues that I have to do so that those probelems will be improved.

please notice that the observation gauages are in the middle of my watershed

1. Upstrean ---- Performance Metrics_Ch47_H043--- NSE : 0.0314 PBIAS : 2.43% ME : -3.1037 RMSE : 319.2123 R² : 0.0314 2. Downstream --- Performance Metrics_Ch102_H002--- NSE : -0.5486 PBIAS : -87.06% ME : 16.8799 RMSE : 32.6899 R² : -0.5486 Thank you for your help in davance.