intro story DELWAQ


DELWAQ is the engine of the D-Water Quality and D-Ecology programmes of the Delft3D suite. It is based on a rich library from which relevant substances and processes can be selected to quickly put water and sediment quality models together.

The processes library covers many aspects of water quality and ecology, from basic tracers, dissolved oxygen, nutrients, organic matter, inorganic suspended matter, heavy metals, bacteria and organic micro-pollutants, to complex algae and macrophyte dynamics. High performance solvers enable the simulation of long periods, often required to capture the full cycles of the processes being modelled.

The finite volume approach underlying DELWAQ allows it to be coupled to both the structured grid hydrodynamics of the current Delft3D-FLOW engine and the upcoming D-Flow Flexible Mesh engine (1D-2D-3D) of the Delft3D Flexible Mesh Suite (or even other models such as TELEMAC).

'DELWAQ in open source' is our invitation to all leading experts to collaborate in further development and research in the field of water quality, ecology and morphology using Delft3D. Feel free to post your DELWAQ related questions or comments in this dedicated forum space. If you are new to DELWAQ, the tutorial (in the user manual) is a good place to start. A list of DELWAQ related publications is available here.




Sub groups
D-Flow Flexible Mesh

Cohesive sediments & muddy systems


Message Boards

"merging com files ..restarted hydrdynamic files...particle tracking"

shanas pr, modified 2 Years ago.

"merging com files ..restarted hydrdynamic files...particle tracking"

Padawan Posts: 29 Join Date: 10/20/11 Recent Posts

Hai all

I am in a process of doing particle tracking module from the successful hydrodynamic flow results.

steps followed 

1.Activated the 'Export WAQ' in the output tab of the GUI, all the necessary files, including ddb file, are automatic created

2.ddcouple done the parallel domain merging and eventually given as input to the PART domain..works like a champ !!


Now my issue is I have set of flow  simulation with the same setup say starting from  1) 1/1/2017- 20/1/2017  and one restarted in separate folder 2) 20/1/2017- 28/2/2017
I would like to combine both as one com* hydrodynamic files which would be ready to use for particle tracking.


Some options i tried as mentioned in the previous comments 1) waq>defineinput>hydrodynamics>combine which is failed and (note : bringing very large files  to windows platform and doing combining task is tedious task)

looking forward for  effective solution.




Michelle Jeuken, modified 2 Years ago.

RE: "merging com files ..restarted hydrdynamic files...particle tracking"

Jedi Knight Posts: 154 Join Date: 1/21/13 Recent Posts



You might want to try this version of agrhyd, a tool to manipulate hyd-files. It has a feature to merge partial hyd-files and their restarts from a FLOW run. It is run from a command prompt using:


agrhyd <ini_name>.ini

In the folder win64/default is an example agrhyd.ini with limited documentation of the options. You could try making an ini-file that contains:


No aggregation options are needed. Check the log, and the output hyd-file. It might be that if the first period intentionally stops at 20/1/2017, the end date in the combined hyd-file might be 20/1/2017, but the vol/flo/etc files actually contain data until 28/2/2017. The size of the output should be about the sum of the two separate files for the vol/flo/etc files.




yu jia xin, modified 2 Years ago.

RE: "merging com files ..restarted hydrdynamic files...particle tracking"

Youngling Posts: 5 Join Date: 12/1/18 Recent Posts

Hello michelle, I am now self-study water quality module, used to study the numerical simulation of pollutant transport and diffusion along the coastal port. The previous hydrodynamic module has been basically completed and verified reasonably. Now I am following the manual to learn the water quality module. You also know The construction of the water quality module involves a lot of biochemistry knowledge, so I feel a little difficult to learn through the model manual. I would like to ask if you have any guidance or suggestions for learning the water quality module. Thank you very much!