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Post-Construction | Section 2: Storm Water Management | 407

SWPPP Cut Sheet:

PURPOSE & DESCRIPTION

Vegetated retaining walls are a green alternative for retaining walls that offers higher aesthetic appeal than conventional block or concrete systems. Vegetated retaining walls are a vegetated mechanically stabilized earth (MSE) system that is reinforced with vegetation and geotextile support to form a green wall that ‘locks’. The locking system is created by the integration of geogrid, vegetation and a fascia made from Filtrexx ® FilterSoxx TM flled with Filtrexx ® GrowingMedia TM . Vegetated retaining walls rely on GrowingMedia TM to provide a fertile growing medium that encourages vegetation establishment and successfully assists in anchoring roots of the vegetation to the wall and site substrate.

APPLICATION

Vegetated retaining walls are to be used where other retaining walls are specifed. These include but are not limited to:

• Steep embankments • Roadside slopes

• Road underpasses (culverts) • Storm water outfalls • Streambanks • Shoreline slopes • Residential retaining walls

Vegetated retaining walls are comprised of 5 primary components: Filtrexx ® Soxx TM used as vegetated fascia, flling the Soxx ™ with Filtrexx ® GrowingMedia TM , geogrid wrapped around flled fascia Soxx ™ , backfll behind fascia, and vegetation

throughout. Components work together to establish a system of Mechanically Stabilized Earth (MSE) with a vegetated fascia.

ISTALLATION

Vegetated retaining walls to meet all Filtrexx ® Specs & use Filtrexx ® GrowingMedia tm . Contractor required to be Filtrexx ® Certifed tm Installer determined by Filtrexx ® International, LLC (440-926-2607; fltrexx. com). Certifcation current if appropriate ID is shown at bid or at time of application (list at www. fltrexx.com). Look for Filtrexx ® Certifed tm Installer Seal.

Excavation and Base Preparation: Prior to construction of Vegetated retaining walls, the area of excavation shall follow plan specifcations. The excavated area shall tightly ft the frst layer of FilterSoxx tm to create a frm foundation. Excavation is a land disturbing activity and requires use of temporary sediment control devices. Compaction of area w/ plate compactor or equivalent is required before adding fll or frst course of FilterSoxx tm . No footings are required; however, a level base buried 10% of the wall may be necessary.

Drainage: Unlike hard-walls, a drainage zone behind the face of the Vegetated retaining walls may not be required as the FilterSoxx TM fascia is highly permeable. This permeability greatly reduces hydrostatic pressure and facilitates hydration of the GrowingMedia TM and fascia vegetation. Where increased drainage is desired or is required for high-fow areas, stone may be added to the GrowingMedia TM in the frst and/or second

Section 2: Storm Water Management – Post-Construction

Filtrexx ® Vegetated Retaining Walls

Vegetated Mechanically Stabilized Earth (MSE) Technology