Changes

===Overflow elevation===

===Overflow elevation===

The invert of the overflow should be placed at the maximum water surface elevation of the practice. i.e. the maximum ponding depth.  

The invert of the overflow should be placed at the maximum water surface elevation of the practice. i.e. the maximum ponding level.  

A good starting point is around 300 mm over the surface of the practice. However, consideration should be given to public safety and drainage time for the ponded water to drain.  

A good starting point is 150 to 350 mm above the surface of the mulch cover. However, consideration should be given to public safety, whether or not an underdrain is included, and the time required for ponded water to drain through the filter bed surface (must drain within 48 hours).  

See [[Bioretention: Sizing#Additional step for system without underdrain|Bioretention]] and [[Stormwater planters]]

See [[Bioretention: Sizing#Additional step for system without underdrain|Bioretention]] and [[Stormwater planters]]