Changes

{{:Reservoir gravel}}

{{:Reservoir gravel}}

===Choker course===

===Choker course===

{{:Choker layer}}

{{:Choker layer}} [[Geotextiles]] may be used to separate the underdrain from native soils on the vertical faces.

 

[[Geotextiles]] may be used to enclose the underdrain on the vertical faces. It's use in horizontal layers within systems is not recommended as it has been demonstrated to [[clogging|clog]] over time in many installations.

==Alternative Technology==

==Alternative Technology==