Changes

<p>An internal water storage zone (IWS or IWSZ) is created by including an upturned 90 deg on the outflow pipe to force an elevated outlet. For practical reasons, this is commonly applied within a manhole or other nearby piece of infrastructure, rather than  being buried directly adjacent. The effect  is to create longer term, water-logged, low-oxygen environment within the bottom of the bioretention cell. <br>

<p>An internal water storage zone/reservoir (IWS or IWSZ) is created by including an upturned 90 deg on the outflow pipe to force an elevated outlet. For practical reasons, this is commonly applied within a manhole or other nearby piece of infrastructure, rather than  being buried directly adjacent. The effect  is to create longer term, water-logged, low-oxygen environment within the bottom of the bioretention cell. <br>

This has two primary benefits:

This has two primary benefits:

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