Sizing of the StormTree system is based on ratio of filter media bed to the area of drainage or catchment, as determined by studies and testing carried out by university and LID design centers.  Such factors as the rate of infiltration and depth of the filter media also play an important role in system design and appropriate sizing.

Unlike closed tree box systems, StormTree’s  “open”  design allows for greater flexibility in the design and installation of the filter media area.  Since the dimensions of the media filter is not dependent on the dimensions of a 4-sided “closed” box, treating a larger drainage area doesn’t require building a bigger box.  Filter media dimensions are based on total square footage, not specific shape, length, or width.

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StormTree provides plan-ready CAD designs, detail sheets, and specifications to aid the engineer and installation contractor. Our standard design sheet provides information for our standard configurations.  StormTree provides alternative configurations and customization to satisfy most site constraints.


StormTree has also developed a HydroCAD  model to aid the specifying engineer in the proper sizing of its units.

Contact us for both CAD details and HydroCAD model as well as additional sizing information.