Mass injections serve as a valuable tool for assessing the environmental impacts of additional loading into the water quality model domain. To create a mass injection dataset, it is necessary to have specified mass injection sites (see Creating a New Mass Injection Set), a WQ Constituent Set (Chapter 5), and a Geometry dataset (Chapter 4).

The Mass Injection Set Editor enables users to create one or more Mass Injection Datasets, each containing multiple mass injection locations. At each of these locations, a specified quantity of mass for one or more constituents from the selected WQ Constituent Set will be introduced into the model. Unlike typical injections of concentration, the mass injection method focuses on introducing a load, without requiring an associated flow. This feature is particularly useful for simulating scenarios such as spills or dye studies, where it is necessary to introduce a specific mass of a constituent rather than its concentration.

To complete a mass injection dataset, the prerequisites are the creation of a Geometry dataset (Chapter 4) and at least one WQ Constituent Set (Chapter 5).

Note: The Mass Injection Set is not utilized in any water quality dataset.