EPA SWMM 5.2 Input Template Generator

The EPA SWMM 5.2 Input Template Generator serves as a bridge between spreadsheet-based data preparation and SWMM’s text-based input format. It leverages Excel’s structured tables, data validation rules, and VBA (Visual Basic for Applications) macros to convert tabular inputs—such as subcatchment geometry, conduit properties, rainfall time series, and pollutant buildup/washoff parameters—into properly ordered, commented, and formatted .inp files compliant with SWMM 5.2’s syntax specifications. Each worksheet typically corresponds to one SWMM input section (e.g., [SUBCATCHMENTS], [CONDUITS], [TIMESERIES]), with embedded logic to handle dependencies (e.g., linking subcatchments to nodes, routing flows through links, or assigning land uses to subcatchments). The tool also incorporates built-in error-checking—for instance, verifying that referenced node IDs exist, checking for duplicate object names, ensuring consistent units across sections, and flagging missing mandatory fields—thereby improving model reliability before simulation. Practitioners use it during early-stage design, regulatory submittals, scenario testing, and educational instruction to accelerate model development while maintaining traceability and auditability of input assumptions.