Difference between revisions of "Stone"

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For advice on aggregates used in [[underdrains]], see [[Gravel]]
For advice on aggregates used in [[underdrains]], see [[Gravel]]

Revision as of 17:33, 2 October 2017

Kenollie Rain Garden.jpeg

For advice on aggregates used in underdrains, see Gravel

Stone can serve as a low maintenance decorative feature, but it may also serve many practical functions in an LID practice. Typical stone functions in LID and direction on selection are provided below:

Dissipate flow and prevent erosion at inlets and outlets

  • Angular crushed stone, which will "knit" or lock together and be less likely to shift, is recommended, however, for aesthetic purpose smooth river run stone may be desired.
  • The stone sizing is based on flow velocities at inlets and outlets, but typically ranges between 50 mm and 250 mm.
  • The thickness of the stone bed is twice that of the largest stone diameter.
  • To prevent erosion of soils beneath the stone and the migration of the stone into the soil, the stone bed should be underlain by a drainage geotextile.

Direct and spread flow throughout a large LID facility or to protect narrow channel sections where flow will concentrate

  • While crushed stone will be less likely to shift, river run stone may be used to create a dry stream bed look.
  • The sizing of the gravel will depend on the expected velocities.