Help with “observation wells outside of the model grid” (HOB not written)

[nasrin badrzadeh]

Hi GMS Support,
When I run MODFLOW I get: *“The following observation wells were outside of the model grid and were not written to the .hob file.” All layers share the same projected CRS. Why does this happen, specifically—what condition makes a well be considered “outside” the grid in GMS/HOB?

Thanks,
Nasrin

Nasrin

[Ahmed Askar]

I guess it happens when well coordinates are outside the grid boundaries!! 

Regards,

Askar

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From: mod...@googlegroups.com <mod...@googlegroups.com> on behalf of nasrin badrzadeh <nasrin.b...@gmail.com>
Sent: Saturday, September 13, 2025 9:23:01 PM
To: MODFLOW Users Group <mod...@googlegroups.com>
Subject: [MODFLOW] Help with “observation wells outside of the model grid” (HOB not written)

 

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