I have encountered an issue in my WEAP model, as shown in the attached figures, and I would appreciate your guidance.
When an environmental flow requirement is defined downstream of a reservoir, the model releases a small amount of water during certain periods when the reservoir water level falls below the minimum operating level. I would have expected the release to stop under these conditions.
Could you please clarify whether this behavior is related to the way the environmental flow requirement or minimum flow is defined, or whether it could be caused by other WEAP settings or computational assumptions? I would also appreciate it if you could explain the basis for calculating these releases under such conditions and advise which settings should be reviewed or adjusted to prevent them.
Thank you in advance for your time and assistance.

Fateme,

Let me try and help-

When you say "minimum operating level", what are you referring to? Top of Inactive? Did you populate the net evaporation for this reservoir? Note that I cannot see any figures in the forum.

If so, it may that your reservoir is releasing exactly down to the Top of Inactive and then at the end of the model timestep it loses water to evaporation, leaving the volume slightly below the Top of Inactive.

-Doug