Difference between revisions of "Bioretention: Construction checklist"

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|Gravel for the underdrain should be clean and washed; no fines should be present in the material
|Gravel for the underdrain should be clean and washed; no fines should be present in the material
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|Underdrain pipe material should be perforated and of the correct size (when specified in design)
|Underdrain pipe material should be perforated and of the correct size (when specified in design)
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|A cap should be placed on the upstream (but not the downstream) end of the underdrain (when specified in design)
|A cap should be placed on the upstream (but not the downstream) end of the underdrain (when specified in design)
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|Biomedia should be tested to confirm that it meets specifications
|Biomedia should be tested to confirm that it meets specifications
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|Mulch composition should be correct
|Mulch composition should be correct

Revision as of 00:02, 5 September 2017

Common construction pitfalls can be avoided with careful construction supervision that focuses on the following aspects:

Erosion and Sediment Control
  Bioretention locations should be blocked from construction traffic and should not be used for erosion and sediment control
Proper erosion and sediment controls should be in place for the drainage area
Materials
  Gravel for the underdrain should be clean and washed; no fines should be present in the material
Underdrain pipe material should be perforated and of the correct size (when specified in design)
A cap should be placed on the upstream (but not the downstream) end of the underdrain (when specified in design)
Biomedia should be tested to confirm that it meets specifications
Mulch composition should be correct

Elevations Depth of the gravel and invert of the underdrain Inverts for inflow and outflow points Filter depth? after biomedia is placed Ponding depth provided between the surface of the filter bed and the overflow structure Mulch depth Landscaping and Stabilization Correct vegetation should be planted Pretreatment area should be stabilized Drainage area should be stabilized prior to directing water to the bioretention The following items should be checked after the first rainfall event, and adjustments should be made as necessary: Outfall protection/energy dissipation at concentrated inflow should be stable Flow should not concentrate and should spread evenly over the filter bed Ponded water at the surface of the bioretenton facility must drain within 24 hours of the end of the storm event.
The biomedia should fully drain within a maximum period of 72 hours Excessive sediment accumulation should not be present