This technical note is for the EcoStream Enhanced Treatment – TSS, Phosphorus & Metals. Overview, functionality, treatment processes, design, plants and installation discussed.

The EcoStream Biofiltration System (EcoStream) is a structural stormwater treatment system developed by ADS that provides water quality treatment through settling, filtration, and sorption processes. The system is typically constructed using precast concrete or other structurally adequate containment vessel and can be used for treatment applications across a broad range of urban settings.

The EcoStream system components listed are concrete vault, solid lid or cover, inlet pipe, energy dissipation stones, mulch, biofiltration media, underdrain pipe/stone, high flow bypass with beehive grate, flow control orifice and outlet pipe. A diagram is provided.

Functionality is explained when stormwater runoff enters the unit through a curb inlet or subsurface pipe inlet. After entering the unit, runoff will flow downward via gravity through the EcoStream system. Treated water enters the perforated underdrain pipe and then exits the EcoStream through the outlet pipe. During peak storm events where the treatment capacity of the system is exceeded, runoff will pond up and begin to flow through bypass standpipe. Treatment processes and water quality parameters are outlined.

Design considerations for inverts and elevations discusses the required design head of the system, total depth of the media, depth with trees, and height without plants.

Installation of the EcoStream unit will involve subsurface excavation, placement of sub-base aggregate material, positioning/casting of the vault, and arrangement of the internal components. Proper installation of the unit is crucial to ensure performance in alignment with the parameters specified.

Plants are not required to be utilized but if desired, choice of plant should align with local requirements and/or be chosen by a qualified landscape architect. If guidance is required, ADS can provide a generic plant list for assistance in design. Please refer to local requirements/approvals to determine if plants are required for the EcoStream BioFilter in your area.

A design summary table is provided.