To create a new mass injection set:

  1. From the Mass Injection Set Editor, go to the Mass Injection Set menu and click New. The Create New Mass Injection Set dialog will open.

  2. In the dialog, provide a Name and an optional Description for the new mass injection set.

  3. Next, specify the WQ Constituent Set and the Geometry for the new mass injection set.

  4. Below the Description, two selector panels will be displayed: 

    • Available Mass Injections (inactive mass injection sites)
    • Selected Mass Injections (active mass injection sites)

    The mass injection sites are listed alphabetically in the panels.

  5. By default, the Selected Mass Injections panel contains all mass injection sites in the watershed. Use the panels to move the desired mass injection sites to either the active or inactive lists for the new or edited mass injection dataset.

  6. After making your selections, click OK to close the dialog and save the new mass injection dataset. The created dataset will be added to the navigation bar in the Mass Injection Set Editor (Mass Injection Set Editor – New Mass Injection Set – Example).



Mass Injection Set Editor – New Mass Injection Set – Example

Next, the user must select the constituent to include in the mass injection set for each mass injection site. Here's how to do it:

  1. In the Mass Injection Set Editor, navigate to the selection tree and right-click on the mass injection site of interest. This will open the shortcut menu (Mass Injection Set Editor – Site Shortcut Menu Commands).

  2. From the shortcut menu, select Add/Remove Constituents. The Constituent Selector dialog will open.

  3. In the Constituent Selector dialog (Constituent Selector Dialog Box – Example), users can select or deselect the constituents they wish to include or remove for the selected mass injection site.



Mass Injection Set Editor – Site Shortcut Menu Commands

The Constituent Selector dialog contains several options for managing the selection of constituents for mass injection sites:

  1. Add To All Mass Injection Sites checkbox:

    • Check this box if you want to add the selected constituents to all mass injection sites in the current mass injection dataset.

  2. Available Constituents and Selected Constituents panels:

    • The Available Constituents panel lists all available constituents that can be added.
    • The Selected Constituents panel shows the constituents already selected for the mass injection site(s).

  3. To add constituents:

    • From the Available Constituents panel, select the constituents you want to add to the mass injection site(s).
    • Click the Add button to add the selected constituents one by one.
    • Alternatively, click Add All to add all available constituents at once to the Selected Constituents panel.


Constituent Selector Dialog Box – Example

Click OK to finalize the addition of the selected constituents to the Mass Injection Set Editor. Regarding data sources, users can add mass injection data from two sources:

  1. Constant Value: Allows users to enter a fixed value for the mass injection.
  2. DSS: Enables users to use data from a DSS file, which provides time-series or other dynamic data for mass injections.

For detailed instructions on how to use these two data source options, refer to the Met Data Sources – Overview .