This document is the Rain Gardens + Bioretention StormTech Detail. Cross section examples of the enhanced bioretention with a typical profile are shown.

The enhanced bioretention plan view starts with the parking lot sheet flow draining toward the curb stops. That filters into the stone diaphragm, grass filter strip and optional sand layer. The gravel curtain drain overflow, underdrain collection storage system, berm overflow catch basin and optional outlet are included.

The typical section profile diagram shows the side view from the curb stops, to the stone diaphragm into the planting soil with optional gravel curtain drain. The optional sand filter system is above the HDPE perforated underdrain pipes, StormTech Chambers protected by a layer of filter fabric.

An inset details the 6”-12” ponding over 2”-3” mulch, below that is 2.5”-4” planting soil, filter fabric, StormTech Chambers, HDPE perforated underdrain pipe wrapped in gravel jacket with underdrain.