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Best Management Practice Fact Sheet 3: Grass Channels


426-122 (BSE-271P)

Authors as Published

Authored by David J. Sample, Associate Professor and Extension Specialist, Biological Systems Engineering, Virginia Tech; Laurie J. Fox, Research Associate, School of Plant and Environmental Sciences, Virginia Tech; and Carol Hendrix, student, Biological Systems Engineering, Virginia Tech

This publication is available in an enhanced digital version and PDF.

This fact sheet is one of a 15-part series on urban stormwater management practices.

Please refer to definitions in the glossary at the end of this fact sheet. Glossary terms are italicized on first mention in the text. For a comprehensive list, see Virginia Cooperative Extension (VCE) publication 426-119, “Urban Stormwater: Terms and Definitions.”

Grass channels (GCs) are wide, gently sloping, open channels with grass sides used as a stormwater conveyance system (see figure 1). Grass channels are similar to ditches; however, their side slopes are much more gradual. GCs provide treatment via filtering through vegetation. When compared with traditional curb and gutter, or inlets and pipes, which remove no pollutants, GCs may provide a modest amount of runoff reduction and pollutant removal. The extent of this reduction depends on the underlying soil characteristics, slope, and flow velocity. At higher velocities, stormwater is only conveyed and is not treated. Unlike dry swales, (VCE publication 426-129), GCs do not include a soil media and/or specific storage volume.

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Publication Date

July 1, 2020