Conclusion

This tutorial introduced modeling of post-development runoff from an urban catchment area using GeoSWMM. It demonstrated how a surface runoff collection system is laid out, how to represent the elements of this system, and the effect of imperviousness and different storm events on the catchment’s outlet hydrograph. Comparisons were made for the runoff peaks and total volume between undeveloped and developed scenarios. The key points demonstrated in this tutorial are:

1. The objective of these hydrologic simulations.
2. System description and its elements’ (subcatchments, links and nodes) properties both in undeveloped and developed conditions.
3. Outline of GeoSWMM model development techniques for the study area.
4. Review of necessary model input parameters and simulation options.
5. Interpretation and comparison of model output results.
6. Outline of options for model file export to EPASWMM.

In the next case study, Tutorial 02, the model for the developed site e.g. Tutorial_01D.gdb will be refined further by adding a storm water conveyance network to it and routing the runoff through said network.