Delta Hydro Studio
Browser-based hydrology and hydraulics calculators for practising engineers — no install, report-ready output.
The US land-development standard for TR-55/TR-20 hydrographs and detention pond design.
by HydroCAD Software Solutions
HydroCAD is the tool a huge share of US site-civil drainage reports are built in: SCS/NRCS hydrology (TR-55/TR-20 procedures), rational method, hydrograph routing through ponds and reaches, outlet-structure hydraulics with composite rating curves, and clean report output reviewers recognise on sight.
Its focus is the land-development detention workflow — model the site, size the pond, tune the outlet, print the package — and within that focus it is extremely efficient. It is Windows-only commercial software with a free sampler edition for evaluation.
Other urban stormwater & infrastructure tools covering similar workflow stages.
Browser-based hydrology and hydraulics calculators for practising engineers — no install, report-ready output.
The public-domain engine of urban drainage: dynamic-wave pipe networks, runoff, LID and water quality.
Python interface to the SWMM engine — step through simulations, read state, and control gates in real time.
EPA's free tool for estimating site runoff reduction from green infrastructure, with climate scenarios.
EPA's toolbox for sanitary sewer overflow planning — RDII analysis with the SWMM engine underneath.
Build and read EPA SWMM models as QGIS layers — free GIS-based SWMM model construction.