Boundary Conditions define the water quality conditions for inflows or outflows at the model domain's boundaries. A boundary condition must be established for each simulated constituent and for inflows into the model domain. The Boundary Condition Set Editor automatically generates a list of inflow boundary locations based on the water quality geometry. Boundary condition data must be specified for each modeled constituent at all inflow locations, including the upstream boundaries of the main channel, its tributaries, and local inflows.

The Boundary Condition Set Editor (Boundary Condition Set Editor – View Selection Tree by Location – View Location Data by Summary) allows users to create one or more boundary condition datasets. However, a Geometry Dataset (Chapter 4) and a WQ Constituent Set (Chapter 5) must be created and completed before a boundary condition set can be created. Once a boundary condition dataset is established, the identified geometry dataset and constituent set determine the boundary inflow locations and simulated constituents that need to be defined.

Users have three options for defining boundary condition data for each constituent at each boundary location:

  1. Constant Value
  2. Ambient Value
  3. Time Series Data stored in an HEC-DSS file.

Additionally, the editor allows users to plot and tabulate boundary condition data by location or constituent.



Boundary Condition Set Editor – View Selection Tree by Location – View Location Data by Summary

The prerequisites for creating the Boundary Condition Set include a Geometry Dataset (Chapter 4) and at least one WQ Constituent Set (Chapter 5). The Boundary Condition Set is not required in creating any other water quality dataset.