# Coupling GAIA, and Nestor with Cohesive Sediments

**URL:** <https://opentelemac.org/forum/t/coupling-gaia-and-nestor-with-cohesive-sediments/8019>\
**Category:** NESTOR\
**Created:** [July 9, 2025, 5:33am UTC](https://opentelemac.org/forum/t/coupling-gaia-and-nestor-with-cohesive-sediments/8019 "2025-07-09T05:33:10Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![user\_17591](https://opentelemac.org/forum/letter_avatar_proxy/v4/letter/u/258eb7/32.png) [@user\_17591](https://opentelemac.org/forum/u/user_17591)\
**Post date:** [July 9, 2025, 5:33am UTC](https://opentelemac.org/forum/t/coupling-gaia-and-nestor-with-cohesive-sediments/8019/1 "2025-07-09T05:33:10Z")

</div>

I’m working on coupling Telemac-2D, GAIA, and [name removed] to simulate a dredging activity in a channel. My setup involves two sediment classes: one non-cohesive (in the bed) and one cohesive (only in suspension, not in the bed).

However, when I run the simulation, I encounter the following error:

A L A R M there seems to be mud !

Coupling of [name removed] with mud is not realized

stop in SUBROUTINE NESTOR\_INTERFACE\_GAIA

Is it not possible to couple [name removed] if cohesive sediments are present in the GAIA model, even if they are only in suspension and not part of the bed composition?

Any insights or workarounds would be greatly appreciated.

---

<div class="post-metadata">

**Author:** ![user\_17591](https://opentelemac.org/forum/letter_avatar_proxy/v4/letter/u/258eb7/32.png) [@user\_17591](https://opentelemac.org/forum/u/user_17591)\
**Post date:** [July 9, 2025, 12:33pm UTC](https://opentelemac.org/forum/t/coupling-gaia-and-nestor-with-cohesive-sediments/8019/2 "2025-07-09T12:33:52Z")

</div>

I tried coupling the [name removed] with TELEMAC 2D rather than in the GAIA cas file. The simulation ran without any error. Since I am doing only a dredging operation, i.e., just lowering the bed elevation at some locations, is this method appropriate?

I would highly appreciate expert advice.

Thank you.

---

<div class="post-metadata">

**Author:** ![user\_1612](https://opentelemac.org/forum/letter_avatar_proxy/v4/letter/u/0ea827/32.png) [@user\_1612](https://opentelemac.org/forum/u/user_1612)\
**Post date:** [July 9, 2025, 12:58pm UTC](https://opentelemac.org/forum/t/coupling-gaia-and-nestor-with-cohesive-sediments/8019/3 "2025-07-09T12:58:53Z")

</div>

Hi [name removed],

[name removed] is mainly developed in BAW. We never tested [name removed] with mud. But we guess that it could be possible without changes at least for simple cases. If you remove the STOP in nestor\_interface\_gaia.f you can try.

Wish you look 🙂

[name removed]

---

<div class="post-metadata">

**Author:** ![user\_17591](https://opentelemac.org/forum/letter_avatar_proxy/v4/letter/u/258eb7/32.png) [@user\_17591](https://opentelemac.org/forum/u/user_17591)\
**Post date:** [July 9, 2025, 1:56pm UTC](https://opentelemac.org/forum/t/coupling-gaia-and-nestor-with-cohesive-sediments/8019/4 "2025-07-09T13:56:57Z")

</div>

Thank you [name removed]. I was able to run the simulation with [group removed] sediments. This time I couple the [name removed] in TELEMAC 2D cas file and not the GAIA cas. It did not show any error related to mud/cohesive sediments described in GAIA.

I hope this method is appropriate. Please let me know your views. Thank you again.