Subject: WEAP calibration using Reservoirs Posted: 11/3/2024 Viewed: 709 times
Hello,
I am trying to calibrate my model with observed monthly reservoir storage data and I am currently facing a challenge with my model calibration. After the calibration, a consistent temporal lag was observed between the modeled and observed reservoir storage levels, affecting both peak and low storage conditions. Specifically, the model demonstrates a 1- to 2-month delay in reaching high and low reservoir storage levels compared to observed data.
If anyone has experience with addressing such issues or can offer advice on potential calibration adjustments, I would be most grateful for your guidance. Any insights or recommendations would be invaluable.
Thank you in advance for your support.
Mr. Doug Chalmers
Subject: Re: WEAP calibration using Reservoirs Posted: 11/4/2024 Viewed: 690 times
Mohammadreza,
Are you using a monthly or daily timestep model? How are your inflows calculated?
If you are using a monthly model, consider that the storage results reflect the storage volume at the end of the month. Think about if this corresponds to the date of your observed readings.
If you are using a daily model, then your difference from the observed could be coming from your reservoir inflows or your reservoir releases. Do you have observed flow data either upstream or downstream of your reservoir? How does your modeled flows at these locations compare to the observed? If you see a difference in your inflows and are performing daily catchment rainfall-runoff modeling, then your catchments are holding on to rainfall too long and releasing it too slowly. Please see the Catchment Calibration chapter of the WEAP tutorial, which showcases how adjusting each catchment hydrology parameter affects the streamflow results (https://www.weap21.org/tutorial).