Bioretention: Construction checklist
Revision as of 14:59, 5 July 2022 by SamanthaPelayo (talk | contribs)
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 media depth | |
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 |