SWMM

Install pyswmm with pip, assemble a valid INP file using the stage S5 tools, then run it through the run_swmm tool which uses pyswmm with a CLI fallback. Check continuity errors afterward with check_continuity_errors before trusting results.

Use the S7 coupling tools: convert VIC runoff (mm/day) to SWMM node inflows (m3/s), reuse VIC forcing as SWMM rainfall, and convert CaMa-Flood river stage to SWMM outfall boundary conditions. SWMM outfall discharge can feed back to CaMa-Flood as lateral inflow.

The FLOW_UNITS option silently sets the unit system for all inputs and outputs. If FLOW_UNITS=CMS but pipe diameters are entered in millimeters, SWMM treats them as meters with no warning. Verify every dimensional input matches the selected unit system.

Yes, the S4 stage tools create and assign seven LID control types including bioretention, green roofs, permeable pavement, and rain barrels. Parameter validation enforces constraints like wilting point below field capacity below porosity.

A routing timestep too large for dynamic wave routing is the most common cause. Reduce ROUTING_STEP and WET_STEP so the Courant condition is satisfied for your shortest conduit, then rerun and verify errors drop below 5%.

Water quality tools (pollutant buildup/washoff, treatment), real-time control rules, groundwater aquifers, and hydraulic structures like pumps and weirs are not yet implemented. Coverage is about 69% of SWMM 5.2 capabilities per the capability inventory.