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. The size of the media filter is not dependent on the dimensions of a 4-sided box. Therefore, treating a larger drainage area doesn’t require the building a bigger box. Filter media dimensions are based on total square footage, not specific shape, length, or width.
Think of the StormTree system as an underground rain garden.