Delta Hydro Studio
FreemiumVerified
Browser-based hydrology and hydraulics calculators for practising engineers — no install, report-ready output.
WinTR-55
StableNRCS's official implementation of TR-55 small-watershed hydrology: peaks, hydrographs and storage.
by USDA NRCS
- Pricing
- Gov-Public
- License
- US Government (public domain)
- Commercial use
- Permitted
- Ecosystem
- Standalone
- Platform
- Windows
About WinTR-55
WinTR-55 is the Natural Resources Conservation Service's Windows implementation of Technical Release 55, "Urban Hydrology for Small Watersheds" — the procedure a large share of US drainage manuals still reference for small-site peak discharge and detention sizing. It computes runoff by Curve Number, times of concentration by the NRCS velocity method, and generates hydrographs by the TR-20 engine that now runs underneath.
It shows its age, but it is free, official and universally accepted where TR-55 is specified. For modern workflows, the same methods are available inside HEC-HMS and most commercial drainage suites; WinTR-55 remains the canonical reference implementation.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
Appears in collections
- The Free Drainage Engineer's Toolkit
Zero-budget, reviewer-accepted tools for everyday stormwater and drainage design.
Alternatives to WinTR-55
Ranked by the topics, categories and workflow stages they share with WinTR-55.
HydroCAD
Commercial
The US land-development standard for TR-55/TR-20 hydrographs and detention pond design.
Visual OTTHYMO
Commercial
Hydrologic modeling software for urban and rural stormwater management, master drainage planning, and pond design.
HEC-HMS
FreeVerified
The US Army Corps standard for rainfall-runoff modelling — event and continuous simulation, free to use.
EPA SWMM
Gov-PublicVerified
The public-domain engine of urban drainage: dynamic-wave pipe networks, runoff, LID and water quality.
NetSTORM
Free
CDM Smith's free rainfall statistics and STORM-method screening model — IDF analysis, disaggregation, CSO planning.