Modelling Additional Constituents

MUSIC allows you to represent an alternate water quality constituent in a new or existing MUSIC model. This approach essentially relabels and re-parameterizes the TSS constituent. As a result, the current implementation assumes that the representation of the alternate WQ constituent can be approximated based on TSS.

How to use a New, Pre-Defined Water Quality Constituent

By default, TSS will always be selected as the ‘alternate constituent’ when a new project is created or a previously saved music project is opened. If you would like to replace TSS with an alternate constituent, select ‘Swap Pollutant' from the Settings tab, as shown below.

A new dialog will appear, as shown below:

The available (ie. those that are distributed with MUSIC) constituents can be selected from the ‘Available Constituents’ drop down box. When any item in this drop down box is selected, the associated ‘Consistent Name’ and ‘Abbreviated Name’ will update. These names are used to replace the TSS labels in dialogs and results outputs in music. These pre-defined names can be modified if required.

The constituent data, including the name and parameter information is stored in a *.wqp (water quality parameter) file that is located in a ‘Additional WQ’ folder in the music installation directory. Each constituent that appears in the ‘Available Constituents’ drop down box will be represented by an individual file within this folder.

If you select the ‘Yes’ radio button under ‘Update Existing Nodes?’, the parameter values that are read from the *.wqp file will be read in and will overwrite the corresponding TSS parameter values for all nodes in the current project. If ‘No’ is selected, the existing parameter values will be preserved and only the TSS labels will be updated.

Once the ‘Finish’ button is selected music will update all TSS labels and, if selected, all parameter values. An example is shown below in the node multi-edit dialog:

Similarly, once music has been run, all outputs that were previously identified as TSS will now be identified using the newly specified constituent name.

The constituent information is saved with the music project allowing separate models to be setup, run and saved for different constituents.

How to Incorporate a New, User-Defined Water Quality Constituent

The additional water quality constituent interface allows you to to set up additional constituents and associated parameters.

As discussed, the name and parameter information for each constituent is stored within the *.wqp file located in the ‘Additional WQ’ folder in the music installation directory. To incorporate an additional constituent, make a copy of one of the existing *.wqp files and rename it. This name is what will appear in the ‘Available Constituents’ drop down box within music. Proceed with updating the contents of the *wqp file ensuring that the names of the parameters and the file structure is maintained. Once music is restarted, the newly created constituent and associated name and parameter information will be available for selection.

The following is an example of the water quality constituent dialog after inclusion and selection of a new ‘copper.wqp’ file.

If you receive a *.wqp file from another music user, simply copy it into the ‘Additional WQ’ folder and it will be available for selection the next time you open music.

Note: When using the alternative pollutant, the simulation of treatment within the various measures in music will be as per the TSS treatment, however this can be adjusted within each treatment measure by the adjustment of parameters such as k and C* (refer to Appendix G for further information on setting appropriate values for these parameters).