• InfoWorks WS Pro

Visualizing pollutant concentrations

Graph and simulate the concentrations of pollutants as they move within a network over time.

Tutorial resources

These downloadable resources will be used to complete this tutorial:


Step-by-step Guide

After running and simulating a pollution scenario in InfoWorks Pro, create graphs and animate a theme to visualize and better understand the results.

  1. From the Model Group window, drag-and-drop the Nitrates run into the GeoPlan.
  2. In the Tools toolbar, click Graph.
  3. From the GeoPlan, select a node immediately downstream of the fixed head control unit.

The InfoWorks WS Pro interface, Tools toolbar with Graph selected and highlighted in red; and in the workspace, the Nitrates GeoPlan zoomed in to the selected node, also called out.

  1. In the Select what to graph for dialog box, select Concentration.
  2. Click OK.

A graph displaying nitrate concentration at the selected node in mg/l over a 4-hour period.

The graph shows the concentration jump to 100 at 2:00 on the start date, and then drop back to zero at 6:00 on the same date.

To graph for concentration in the reservoir.

  1. From the GeoPlan, select node 544421.
  2. In the Select what to graph for dialog box, choose Concentration.
  3. Click OK.

The GeoPlan with the reservoir selected in red, and the Select what to graph for dialog box with Concentration 01 (mg/l) and OK selected.

This graph shows a sharp increase in nitrate concentration at 2:00 and a more gradual decrease over several days. The concentration levels are much lower than those of the node, because it is being diluted in the volume of the reservoir.

A graph displaying nitrate concentration in the reservoir in mg/l over a 7-day period.

To create a new theme group for a visual representation of how the nitrate pollution spreads and dissipates over the course of the simulation:

  1. From the Model Group window, under Theme Groups, drag-and-drop the WQ Contours control theme into the GeoPlan.
  2. In the Docking windows toolbar, click Thematic Key window.

The Model Group window with WQ Contours highlighted in red, the Docking windows toolbar with Thematic Key window selected, and in the workspace, the WQ Contours GeoPlan open.

  1. Optional: In the Thematic Key, right-click Polygons and deselect Display to remove visual clutter.

Note: Depending on the solute data being modeled, you may need to change the scale of values.

  1. In the Thematic Key, under Contours, select sim.conc01.

The WQ Contours GeoPlan with Polygons no longer displayed, and the Thematic Key with Sim.conc01 selected.

Notice in the Contours: Concentration dialog box, under Ranged Themes, the low end of the scale is already set to 0.

  1. In the bottom row of the table, in the Fix column, select the checkbox.
  2. In the same row, Value column, enter the value “3”.
  3. At the top of the Value column, click AutoScale to scale the values between 0 and 3.
  4. Optional: Adjust the fill colors.

The Contours: Concentration dialog box, Ranged Themes section, with a new Value entered and Fix selected, both highlighted in red, and AutoScale selected and called out.

  1. Click Apply.
  2. Click OK.
  3. In the GeoPlan Properties and Themes dialog box, click Apply.
  4. Click OK.

The network is now overlaid with the contour theme, showing areas of high concentration in orange and areas of low concentration in blue.

  1. In the Replay toolbar, click Play to advance the simulation and see how the gradients change over time.

The Replay toolbar with Play selected and highlighted in red, and in the GeoPlan, the simulation of nitrate concentrations over time.

Notice how the nitrate concentrations are higher in high-flow areas of the network, and nonexistent in other areas. As you reach the end of the simulation, the concentration gradually decays before disappearing completely.