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→Pretreatment and inlet
The [[construction]] guidance in this section applies to all sub-surface and ground-level LID practices: [[bioretention|bioretention gardens]], [[bioswales]], [[rain gardens]], [[exfiltration trenches]], [[enhanced swales]], [[permeable pavements]], [[infiltration trenches]], [[infiltration chambers]], and [[soakaways]]. In general, this section describes construction and inspection processes for below ground installed materials and infrastructure that are part of the LID practices noted above.
The [[construction]] guidance in this section applies to all sub-surface and ground-level LID practices: [[bioretention|bioretention gardens]], [[bioswales]], [[rain gardens]], [[exfiltration trenches]], [[enhanced swales]], [[permeable pavements]], [[infiltration trenches]], [[infiltration chambers]], and [[soakaways]]. In general, this section describes construction and inspection processes for below ground installed materials and infrastructure that are part of the LID practices noted above.
{{:Disclaimer}}
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==Trench, Chamber, and Perforated Pipe Installation==
==Trench, Chamber, and Perforated Pipe Installation==
The guidance provided in this section is applicable for the construction of soakaway pits, infiltration chambers, infiltration trenches, and exfiltration pipes of varying size and shape, since the installation of each of these features is similar. The [https://assets.ads-pipe.com/m/446afe5e1aafda1a/original/MC-7200-StormTech-Chamber-Installation-Guide.pdf StormTech Installation Guide]<ref>Advanced Drainage Systems. 2022. StormTech® Installation Guide MC-7200 Chamber. https://assets.ads-pipe.com/m/446afe5e1aafda1a/original/MC-7200-StormTech-Chamber-Installation-Guide.pdf</ref> is a key resource for understanding the construction of these features.
The guidance provided in this section is applicable for the construction of soakaway pits, [[infiltration chambers]], [[infiltration trenches]], and [[exfiltration trenches|exfiltration pipes]] of varying size and shape, since the installation of each of these features is similar. The [https://assets.ads-pipe.com/m/446afe5e1aafda1a/original/MC-7200-StormTech-Chamber-Installation-Guide.pdf StormTech Installation Guide]<ref>Advanced Drainage Systems. 2022. StormTech® Installation Guide MC-7200 Chamber. https://assets.ads-pipe.com/m/446afe5e1aafda1a/original/MC-7200-StormTech-Chamber-Installation-Guide.pdf</ref> is a key resource for understanding the construction of these features.
[[File:Chamber-excavator.jpg|400px|thumb|right|An excavator covering units of unfinished infiltration chamber rows with perimeter stone. Stone can be applied progressively as the rows are completed to ensure that space is provided for the excavator to work within the LID footprint. (Photo Source: [https://www.mswmag.com/g/product-focus/2015/08/stormwater_management_advanced_drainage_systems_stormtech_mc_4500 Municipal Sewer & Water])<ref> Municipal Sewer & Water. 2022. Photo. Accessed in July 8 2022:https://www.mswmag.com/g/product-focus/2015/08/stormwater_management_advanced_drainage_systems_stormtech_mc_4500</ref>]]
[[File:Chamber-excavator.jpg|400px|thumb|right|An excavator covering units of unfinished infiltration chamber rows with perimeter stone. Stone can be applied progressively as the rows are completed to ensure that space is provided for the excavator to work within the LID footprint. (Photo Source: [https://www.mswmag.com/g/product-focus/2015/08/stormwater_management_advanced_drainage_systems_stormtech_mc_4500 Municipal Sewer & Water])<ref> Municipal Sewer & Water. 2022. Photo. Accessed in July 8 2022:https://www.mswmag.com/g/product-focus/2015/08/stormwater_management_advanced_drainage_systems_stormtech_mc_4500</ref>]]
#If specified by the design, roll geotextile parallel to rows over the top of stone. Provide sufficient overlap, as specified by the manufacturer.
#If specified by the design, roll geotextile parallel to rows over the top of stone. Provide sufficient overlap, as specified by the manufacturer.
'''Note:''' where many rows of infiltration chambers are being installed, it may be advisable to construct the chamber rows piece-wise as the application of perimeter stone progresses to provide space for excavators to apply the stone from on top of the stone base. See the adjacent photo for an example.
<small>'''Notes:''' where many rows of infiltration chambers are being installed, it may be advisable to construct the chamber rows piece-wise as the application of perimeter stone progresses to provide space for excavators to apply the stone from on top of the stone base. See the adjacent photo for an example.</small>
'''Key Inspection Points:'''
'''Key Inspection Points:'''
==Curbing==
==Curbing==
[[File:20150618 114542.jpg|thumb|350px|right|Improper elevation at the curb cut, impeding the inflow to enter the LID facility (bioretention) (Photo source: CVC, 2015)]]
It is very important to make sure that the contractor responsible for curb construction understands curb cut designs and elevations. This is often a new technique for contractors, and they may not understand the overall concept of water in the gutter line being directed behind the gutter.<br>
'''Construction Steps:'''
#Place the right forms (rolled curve vs standard) in the inlet location.
#Pour concrete.
#Shape the inlet
#Add the river stone on top of the fresh concrete (if applicable)
#Provide sufficient curing time, according to ([https://www.csagroup.org/store/product/2420232/#:~:text=and%20specialty%20concretes.-,A23.,A%20sister%20standard%20%E2%80%93%20CSA%20A23 CSA, 2009])<ref> CSA. 2009. A23.1-09/A23.2-09 (R2014). Concrete materials and methods of concrete construction/Test methods and standard practices for concrete. standard A23.1-09. https://www.csagroup.org/store/product/2420232/#:~:text=and%20specialty%20concretes.-,A23.,A%20sister%20standard%20%E2%80%93%20CSA%20A23 </ref>
[[File:P1160129.jpg|thumb|400px|right|Ensure curb granular base (granular A) does not spill over into LID infiltration area. If material spills over, remove as best as possible while still maintaining the 2:1 slope for curbing. (Photo source: CVC, 2012)]]
'''Key Inspection Points:'''
*Use of proper curb form by sub-contractor.
*Curb type aligns with design.
*Curb cut location, type and dimension aligns with design.
*Designated concrete wash out is in place and away from LID facility.
'''Mistakes to Avoid:<br>'''
*Elevated curb cuts and reverse slopes (sloping from back of curb towards instead of depressing from gutter line towards the back).
*Wrong curb cut width size.
*Use of wrong curb form.
*Concrete wash out within or upstream of LID facility.
*Ensure curb granular base (granular A) does not spill over into LID infiltration area. If material spills over, remove as best as possible while still maintaining the 2:1 slope for curbing
*Lack of communication to concrete contractor or ready-mix driver explaining the function and importance of protecting the LID feature.
For more information on curb cuts, see these pages: [[Curb cuts]], [[Curb cuts: Gallery]] and [[Bioretention: Streetscapes]]<br>
==Pretreatment and inlet==
==Pretreatment and inlet==
Pre-treatment structures are most cost effective when they slow down incoming flows, collect sediment for easy clean out, and slowly release water to the bioretention facility mitigating erosion. [[Pretreatment]] structures/strategies can include [[curb cuts]], [[Aggregates]], proprietary devices like filters or [[Oil and Grit Separator|hydrodynamic separators]], [[vegetation]], [[Flow through riser|concrete sumps]], [[Pretreatment#Concentrated underground flow|membrane filters]], [[Pretreatment#Concentrated overland flow|overland flow sumps]], etc.
'''Construction Steps:'''
*Installation of [[pretreatment]] features will vary based upon type. Similarly, installation timeline will range with type and could occur at excavation and mass grading, curb work or at finishing grade. Given pre-treatment features are typically integrated with the LID inlet coordination amongst multiple sub-contractors is sometime needed. The following details steps for various pre-treatment types:
*[[Vegetation]]: Follow the guidance shown below in the section “Plant Material Verification and Installation”
*[[curb cuts|Curbing]]: Follow the guidance shown above in the section “Curbing”.
*[[Aggregates|Aggregate]]: Follow the guidance shown above in the section “Stone reservoir”.
<gallery mode="packed" widths=300px heights=300px>
IMG_0891.jpg|Aggregate material (rock) installed as the inlet and pre-treatment device in the rain garden at Glendale P.S. in Brampton, ON. The runoff comes from a vegetated swale into the inlet, conveying it into the rain garden. (Photo Source: CVC, 2021)
IMG_0744.jpg|Aggregate material (rock) installed as the inlet and pre-treatment device in the rain garden at Glendale P.S. in Brampton, ON. The runoff comes from a vegetated swale into the inlet, conveying it into the rain garden. (Photo Source: CVC, 2021)
IMG_0788-1.jpg|Aggregate material (rock) installed as the inlet and pre-treatment device in the rain garden at Glendale P.S. in Brampton, ON. The runoff comes from a vegetated swale into the inlet, conveying it into the rain garden. (Photo Source: CVC, 2021)
</gallery>
[[Category:Gallery]]
====Proprietary pre-treatment device====
#Excavate and prepare base for proprietary pre-treatment device according to design.
#Install proprietary pre-treatment device according manufacturer directions.
#Manufacturer representative may need to confirm proper installation and functioning through approved testing and inspection. <br>
<gallery mode="packed" widths=275px heights=275px>
P1160102.jpg|Installation of Jellyfish filter and sorbtive media vault at the IMAX bioswale project in Mississauga, ON. (Photo Source: CVC, 2012)
P1160117.jpg|Installation of Jellyfish filter and sorbtive media vault at the IMAX bioswale project in Mississauga, ON. (Photo Source: CVC, 2012)
P1160121.jpg|Installation of Jellyfish filter and sorbtive media vault at the IMAX bioswale project in Mississauga, ON. (Photo Source: CVC, 2012)
</gallery>
[[Category:Gallery]]
'''Key Inspection Points:'''
*Verify that the correct pre-treatment device ([[pretreatment|jellyfish filter]], [[vegetation]], [[curb cuts|curbing]], etc.) is being installed.
*Verify that all components of the pre-treatment device are installed
*Verify correct size and location of pre-treatment device.
*Verify correct elevation, slope, and footing according to design
*Is it tied into the curb, downspout, or other inlet? Or could happen before the curbing?
*Wet weather performance check:
**Does it work?
**Is water entering the LID facility properly?
**Is sediment and debris accumulating?
**Is it dissipating erosive forces?
'''Mistakes to Avoid:'''
*Pre-treatment component parts are missing
*Grading/elevation errors that deviates from design
**Incorrect pipe inverts causing short circuiting
**Insufficient grade drop or slope into pre-treatment to ensure positive flow of water
**Improper grading from pre-treatment to LID feature inhibiting positive flow
**Insufficient sump depth to account for sediment and debris accumulation
*Using wrong concrete forms if concrete curbs are part of pre-treatment.
For more information about pre-treatment strategies and their design, visit these page(s): [[Pretreatment]] and [[Pretreatment features]].
==References==
==References==
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