Changes

*Concrete vaults and plastic crates are often rectangular-shaped. Concrete vault systems can, in some circumstances, be employed without any additional cover. However, a minimum of 20 cm cover is recommended for most applications. Where this cover is planting soil this can support turf grass. Greater planting soil depths are required to support more deeply rooting plants like perennials and shrubs (45 to 60 cm) and trees (85 to 100 cm).

*Concrete vaults and plastic crates are often rectangular-shaped. Concrete vault systems can, in some circumstances, be employed without any additional cover. However, a minimum of 20 cm cover is recommended for most applications. Where this cover is planting soil this can support turf grass. Greater planting soil depths are required to support more deeply rooting plants like perennials and shrubs (45 to 60 cm) and trees (85 to 100 cm).

For information about constraints to infiltration practices, and approaches and tools for identifying and designing within them see [[Infiltration]].

Infiltration chambers can be constructed over any soil type, but hydrologic soil group (HSG) A and B are best for achieving water balance objectives.  Native soil infiltration rate at the proposed facility location and depth should be confirmed through in-situ measurements of hydraulic conductivity under field saturated conditions.  For guidance on infiltration testing and selecting a design infiltration rate see [[Design infiltration rate]].

 

For more information about constraints to infiltration practices, and approaches and tools for identifying and designing within them see [[Infiltration]].

===Geometry and Site Layout===

===Geometry and Site Layout===