Design Toolbox

retain-it Stormwater System Design Calculator

You can download a copy of our retain-it Stormwater System Design Calculator here.  Add your system design inputs to the yellow highlighted fields at the top of the first sheet to create a print-friendly preliminary system report for your stormwater project. Click to download


Design engineers are invited to use these retain-it AutoCAD module and system drawings to better represent and personalize their given stormwater project.
Standard System & Module Drawings .dwg
Stacked System & Module Drawings .dwg
Treatment System & Module Drawings .dwg
Heavy Duty Frames & Covers – ARND430RI .dwg


retain-it modules can be easily modeled with the HydroCAD Stormwater Modeling System, allowing simplified calculation of the chamber’s storage and infiltration behavior. The HydroCAD Chamber Wizard also performs automated chamber system layout, and simplifies the process of designing a chamber system meeting specific storage and footprint requirements. Click here for details. Click for details
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