What This Tutorial Covers

This tutorial serves as a hands-on guide for professionals using GeoSWMM, with a focus on the practical application of hydrologic and hydraulic modeling for urban drainage system design. It is intended for users who already have a working knowledge of hydrology, hydraulics, stormwater management modeling, model input data in ArcGIS Pro and the use of EPA SWMM elements and flow routing methods for representing drainage systems.

The tutorial walks users through the process of adding a conveyance network to the post-development model created in Tutorial 01. It emphasizes key tasks such as incorporating hydraulic routing into the existing model, defining the conveyance network, and estimating network dimensions based on three 2-hour synthetic storm events with return periods of 2- years, 10- years, and 100- years. For simplicity, the tutorial uses open channels with circular cross sections to convey the flow. These skills are especially relevant for engineers and planners involved in stormwater drainage design and the evaluation of infrastructure capacity under varying design storms.

Users will learn how to extend a runoff-only model into a more complete drainage system model by introducing a conveyance network, applying design storm criteria, and assessing how storm magnitude influences hydraulic design requirements. This tutorial complements the GeoSWMM User’s Manual by offering a structured, example-driven walkthrough of real-world modeling scenarios.

The following sections begins a step-by-step demonstration of the worked example project, guiding users through each stage of extending the post-development model with a conveyance network and simulating its performance under multiple design storm conditions.