← Design tools
Design tools
Stormwater network
Build a simple catchment and pipe tree, then size DN against Colebrook-White capacity and velocity limits.
rainfall
Design rainfall
BOM IFD fills a default intensity. Your answers stay if you go back.
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BOM IFD fills a default intensity (120-min 10% AEP depth ÷ 2).
Results are indicative for early design only. Confirm sizing with a licensed plumber, hydraulic consultant, or GRAF Australia for site-specific conditions and council requirements.
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