SWMMVis (the OpenSWMM GUI) is a Qt 6 / C++ GIS-based desktop application for building, running, and analysing SWMM 6.0 storm-water models with the next-generation OpenSWMM engine. It reads and writes standard SWMM .inp files, adds a GIS map canvas with coordinate reference systems and web/GIS data layers, and provides graphical workflows for supported engine capabilities — dynamic-wave and finite-volume 1D routing, 2D overland flow on unstructured meshes, 1D–2D coupling, advection–reaction–dispersion transport, multispecies reaction systems, heat transport, water age, groundwater exchange, streets and inlet junctions — through dialogs, tables, plots, and animated maps.

This manual is organised in five parts. Part I gets you oriented; Parts II–IV are reference chapters, one per capability area; Part V walks through small but complete case studies that exercise the engine end-to-end. Every chapter follows the same pattern: what you'll do, where to find it, a step-by-step reference, tips and gotchas, and related chapters.

SWMMVis main window — ribbon; map canvas; Layers; Object Browser; Properties and Message Logs panels

Part I — Getting started

01 — Introduction and Getting Started — what SWMMVis is, installation, first launch, the Welcome page
02 — The Interface — window layout, ribbon and menus (every item), panels, status bar, command palette, shortcuts
03 — Working with Projects — projects (.inp / .oswp), open, save, recents, multiple projects, undo, portability, user flags
04 — Preferences — the Preferences dialog

Part II — Map, GIS and layers

05 — The Map Canvas — the map canvas: pan, zoom, measure, export and print
06 — Coordinate Reference Systems — coordinate reference systems
07 — Layers and Data Sources — the Layers panel and every data source (vector, raster, WMS/WMTS/WCS, WFS, XYZ tiles, basemaps, delimited text)
08 — Styling, Labels and Legends — symbology, labelling, colour ramps, the Style Manager, legends
09 — Selection and Search — selecting, searching, and tracing upstream/downstream
10 — Object Browser, Properties and Section View — the Object Browser, the Properties panel, compound editors, the Section View
11 — Attribute Tables and the Attribute Calculator — attribute tables, selection queries and bulk edits, mesh tables, tabular data layers
12 — Editing the Network on the Map — drawing and editing the network on the map, annotations, importing GIS features
12A — Editable GIS Feature Layers — creating editable GIS layers; drawing geometry; editing fields and vertices; preparing mesh inputs

Part III — Building a model

13 — Hydrology: Rain Gages, Subcatchments, LID, Snow, Groundwater and RDII — rain gages, subcatchments, infiltration, LID controls, snowpacks, aquifers and groundwater, unit hydrographs / RDII
14 — Hydraulics: Nodes, Links, Cross-Sections, Streets, Inlets and Controls — nodes, links, cross-sections and transects, streets and inlets, control rules, inflows
15 — Climate: Temperature, Evaporation, Wind, Snowmelt and Solar Radiation — temperature, evaporation, wind, snowmelt and solar radiation
16 — Water Quality, Reaction Systems, Water Age and Heat — pollutants, land uses, build-up/wash-off, treatment, initial quality, reaction systems, water age, heat transport
17 — Time Series, Curves, Patterns and Calibration Data — time series, curves, patterns, calibration data
18 — Simulation Options — the Simulation Options dialog, page by page
19 — 2D Overland Flow: Meshes, Cell Parameters, Boundary Conditions and 1D–2D Coupling — 2D overland flow: mesh generation, mesh editing, cell parameters, boundary conditions, 1D–2D coupling

Part IV — Running simulations and analysing results

20 — Running a Simulation — running, pausing and cancelling a simulation; status, logs, live results, reports, mass balance
21 — Results Layers, Result Styling and Animation — opening 1D and 2D results, results layers, result styling, legends and map animation
22 — Time-Series and Comparison Plots — time-series and comparison plots, observed data, statistics, scatter plots, export
23 — Profile Plots — profile plots along 1D paths, 2D mesh profiles, terrain profiles
24 — Tabular Results and Reports — result columns in the attribute table, the statistics dashboard, the report viewer and export
25 — Analysis Tools: Flow Balance, Travel Time, Rainfall Visualisation, 2D Cell Time Series — flow balance, travel time, rainfall visualisation, 2D cell time series, statistics dashboard

Part V — Tutorials and case studies

Start with T1 or T2 for the 1D workflow. T5 includes a tracked 2D boundary example, and T7 includes a transport model. T3, T4 and T6 describe historical demo bundles that are not included in a fresh checkout; their availability notes identify the missing inputs and validation work. T8 requires its larger catchment data and dependent files. Runtime depends on the model and hardware.

T1 — Site Drainage with Water Quality — a 1D site drainage model with water quality (build-up/wash-off)
T2 — Streets, Inlets and the Inlet Junction — streets, HEC-22 inlets and the SWMM 6 inlet junction
T3 — From a DTM to an Animated 2D Inundation Map — from a DTM raster to an animated 2D inundation map
T4 — Spill and Drainback Between a Pipe Network and a 2D Plaza — capped street inlets coupled to a 2D surface
T5 — Culverts, Embankments, Boundary Conditions and Edge Conveyance — culverts under embankments, edge boundary conditions and edge conveyance
T6 — A Stand-alone 2D Overland-Flow Model — a stand-alone 2D overland-flow model with system rainfall
T7 — Transport: ARD Solvers, Reaction Systems, Water Age and Heat — advection–reaction–dispersion transport, reaction systems, water age and heat
T8 — Bellinge: A Real-World Catchment with an External Mesh; DEM; Long Rain Records and Basemaps — a real-world catchment: external mesh, DEM, long rain records and basemaps
T9 — Layered LID Storage and Pollutant Treatment — layered storage-node LIDs and pollutant treatment
T10 — Distributed LIDs: Active Control and Receiving-Water Backwater — distributed LIDs; active control; receiving-water backwater and pollutant balance
T11 — Sewer-Surface Exchange: Rubinato Laboratory Comparison — laboratory sewer/surface comparison; synthetic surcharge and drainback; validation limits

Appendices

A1 — Keyboard Shortcuts — default keyboard shortcuts
A2 — File Formats — files SWMMVis reads and writes
A3 — Plugins — engine and GUI plugins
26 — GUI extensions — installing and using GUI extensions
A4 — Performance and Redraw Policy — redraw policy, large models and performance tuning
A5 — Troubleshooting — common problems and their fixes
A6 — About, Credits and Licences — about, credits and licences
A7 — Reference Tables — units, soil, curve number, Manning's n, culvert and pipe-size tables
A8 — Error and Warning Codes — every numbered error and warning
A9 — Object Property Index — which chapter documents which object property

Conventions used in this manual

Menu paths are written File → Import → Add Vector Data…. The same commands are on the ribbon; the ribbon tab is named in the Where to find it section of each chapter.
Keyboard shortcuts are the defaults; you can change any of them in Help → Keyboard Shortcuts… (see A1 — Keyboard Shortcuts).
SWMM input-file keywords are written in MONOSPACE and refer to sections and options of the .inp file; the engine's own documentation describes their numerical meaning.
Figures marked FIGURE PLACEHOLDER and videos marked VIDEO PLACEHOLDER are still to be captured. See docs/manual/README.md for how to add them.