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#The soil in the bottom of the excavation should be ripped to promote greater infiltration.
#The soil in the bottom of the excavation should be ripped to promote greater infiltration.
#Any accidental sediment accumulation from construction should be removed at this time.
#Any accidental sediment accumulation from construction should be removed at this time.
# Excavate subsurface water storage reservoir to base elevation,
#Check base elevation and slope,
#Fracture/rip bottom and roughen side of the excavation to remove smeared surfaces,
#Install optional [[geotextiles]] (or [[liner]] for [[biofilters|biofilter]]); overlapping according to design drawings,
#Install coarse [[reservoir gravel]], and any void forming structures (e.g. [[underdrains]], [[infiltration chambers]], or [[wells]]),
#Check elevation and slope at top of reservoir,
#Install [[choking layer]] and optional geotextile (typically only over the perforated [[pipe]]),
#Check elevation and slope at top of choking layer,
#Install [[filter media]] with additional 30 cm over finish grade of the filter bed,
#Thoroughly saturate and allow to settle for at least one week. After this time, tamp manually to check settling is complete. Alternatively, installations made in the fall can be left to settle over the whole [[winter]] season at this point,
#Install temporary erosion and sediment control practices,
#:'''Conduct all other site construction activities (buildings/servicing etc.)'''
#Check condition of bioretention after settling period, remediate any deficiencies,
#Install curbs and pavements and concrete [[pretreatment]] devices,
#Check elevations of [[curb cuts]] and other [[inlets]]
#Install erosion control to all inlets!!
#Remove excess filter media along with any accumulated construction sediment,
#Install any surface applied [[additives]],
#Conduct fine grading to surface of filter bed, checking elevations/slopes/compaction,
#Apply [[stone]] or [[mulch]] cover for decorative systems, or [[turf reinforcement]] for grassed systems,
#Install [[erosion control blankets]] or matting
#[[Plants|Plant]] or lay [[turf|sod]],
#Saturated system thoroughly to settle filer media particles around the roots of new plants,
#Irrigated the system as required to establish healthy vegetation cover,
#Inspect and remediate deficiencies after any significant rainfall within the next 3 months or remainder of the first growing season.
===Infiltration construction===
{{:Infiltration: Construction}}
<h4>Bioretention specific construction</h4>
The options at this step depending on the design:<br>
<strong>Full infiltration:</strong>Pack 50 mm diameter clear stone to storage design depth, top with 100 mm of pea gravel and the geotextile drainage fabric.<br>
<strong>Partial infiltration:</strong>Place design depth of 50 mm diameter clear stone for the infiltration volume on bed and then lay the perforated underdrain pipe over it. Pack more clear stone to 75 mm above the top of the underdrain, top with 100 mm of pea gravel and the geotextile drainage fabric.<br>
<strong>No infiltration:</strong> Place an impermeable liner on the bed with 150 mm overlap on sides. Lay the perforated underdrain pipe, Pack 50 mm diameter clear stone to 75 mm above top of underdrain, top with 100 mm of pea gravel and the geotextile drainage fabric.<br>
<strong>Rain garden:</strong> No storage or drainage is required, biomedia is laid onto native soils. <br>
*Biomedia is installed over the geotextile fabric in 0.3 m lifts until desired top elevation is achieved. Each lift must be thoroughly wetted and drained before adding the next. Wait three weeks to check for settling, and add additional media and regrade as needed.<br>
*Prepare planting holes for any trees and shrubs, install vegetation, and water accordingly.
*Install any temporary irrigation.
*Plant landscaping materials as shown in the landscaping plan, and water them weekly in the first two months.
*Lay down surface cover in accordance with the design (mulch, riverstone, or turf).
*Conduct final construction inspection, checking inlet, pretreatment, bioretention cell and outlet elevations.
*Remove erosion and sediment controls, only when the entire drainage area is stabilized
==Checklists==
*[[Bioretention: Construction checklist|Bioretention construction inspection checklist]]
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