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==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 hydrodynamic separators, vegetation, concrete sumps, membrane filters, 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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