StormTree™ is not a closed concrete box, therefore the amount of runoff treated is not based on the size of a concrete structure. StormTree relies on direct infiltration, as well as an expanded engineered media layer to treat larger drainage areas. Our standard 5’X 5′ and 7’X 5′ systems can treat up to 0.50 acres, or greater with a smaller footprint than closed box systems. Our systems can be integrated with conventional stormwater struc- tures, stormwater chambers, drainage piping, or simply as a “stand-alone” system.

Precast Concrete Frame

Can be configured in multiple ways to suit the most demanding site constraints. It is designed to support HS-20 loading and does not need a crane to be installed. The surface is coated with a salt inhibiting epoxy coating, and can be colored to suit an aesthetic requirement. Optional fiberglass frame also available where HS-20 loading requirements are not necessary.

Media Matters

The engineered media within the system serves two important, yet somewhat contradictory functions: (1) provide rapid infiltration; (2) maintain ample soil water to allow for microbial activity and sustain healthy tree growth. We have developed 3 non proprietary media “recipes” each of which provides just the right balance of infiltration and moisture holding capacity and is designed to blend with existing (native) soils assuring unrestricted infiltration and tree root migration. The media is pH neutral and chemically inert therefore guaranteeing that no nutrients are introduced into the subsurface soil matrix.

                                      High Pollutant Removal                            

Reported Pollutant Removal Rates for Tree Filter Systems* 


Removal Rate

Total Suspended Solids (TSS)


  Total Phosphorous


Nitrogen Removal


Total Metals

54% to 88%

Oil and Grease


* Based on published 3rd party testing of generic and proprietary tree filter systems

Tree filters, like other bioretention systems including rain gardens, have a high degree of stormwater pollutant removal capacity. The physical, biological, and chemical remediation functions are hard at work to separate, partition, adsorb, metabolize, and sequester both organic and inorganic constituents in the stormwater train.

We Use Trees In Our Systems

Since the unique open design allows for unrestricted tree root expansion, we have a large ornamental tree list to work with. We primarily incorporate small to medium sized trees which typically achieve a height of no greater than 30 feet. This works particularly well in situations where overhead electrical wires are an issue.