StormTree provides tree filter systems in two design formats:

• (Regulatory) to meet specific state regulatory stormwater management goals.  Some state agencies require 3rd party certification (e.g., Washington Ecology, TAPE) to meet specific pollutant removal (percent concentrations) goals.

• (Non Regulatory) stormwater management providing expected pollutant removal rates based on established field testing results.

 

So what’s the main differences as far as design?

Regulatory systems provide 3rd party certification regarding pollutant removal rates to meet state regulatory approval.  However, specific depth, dimensions and requirements for mulch, soil, underdrain pipe, and tree must be adhered to per the plan details.

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Non regulatory systems provide established pollutant removal rates.  They provide greater flexibility in depth, dimensions and requirements for mulch, soil, underdrain pipe, and tree.