EPA National Stormwater Calculator
Gov-Public
EPA's free tool for estimating site runoff reduction from green infrastructure, with climate scenarios.
Urban Stormwater & InfrastructureStableSuDS & LID DesignStormwater Design
4 tools · Topic
SuDS / LID / WSUD Design Tools
Green infrastructure design — bioretention, permeable pavement, swales, rain gardens — comes with its own sizing rules and performance models. Indexed here: LID modules in mainstream models, dedicated SuDS sizing tools and the guidance-linked calculators reviewers recognise.
EPA SWMM
Gov-PublicVerified
The public-domain engine of urban drainage: dynamic-wave pipe networks, runoff, LID and water quality.
Urban Stormwater & InfrastructureActiveSWMMSewer Modelling
MUSIC
Commercial
eWater's stormwater-quality model — the WSUD assessment standard across Australian councils.
Urban Stormwater & InfrastructureActiveSuDS & LID DesignWater Quality Modelling
Virginia DEQ's official Excel workbooks for stormwater compliance via the Runoff Reduction Method.
Urban Stormwater & InfrastructureActiveSuDS & LID DesignStormwater Design