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Line 110: ''INSERT YOUTUBE LINK: https://www.youtube.com/watch?v=Ng_s2ErvPqk&t=58s <br>''The storage reservoir layer holds and directs the stormwater into the underlying/native soils. The LID facilities, if applicable, should be filled with uniformly graded, washed stone (20 mm – 50 mm) that provides 30 to 40% void space. #Backfill material from outside of the LID facility to avoid compaction and sediment entering the facilities. Use a slinger truck if possible.#Place the material to the elevation and thickness as per the design specifications. Key Inspection Points:*Material arrival to the site: **Check chain of custody**Verify it meets specifications as per design **Verify no debris or fines within the aggregate (it’s a washed stone)*Granular material should be 19 - 50 mm clear stone or as per design. See [[Aggregates]] for further details.*Installed aggregate is at the correct elevation as per design. Mistakes to Avoid:*Accepting material that does not meet design requirements and specifications.*Installing material with heavy equipment from the inside of the LID facility*Installing frozen aggregate. Do not install frozen aggregate*Leaving heavy equipment (excavator) for long periods of time within the LID facility. For more information on the storage reservoir, see the page: [[Reservoir aggregate]].
''INSERT VIDEO: K:\Watershed Management\Integrated Water Management Implementation\Fletchers Creek SNAP\Haggert Ave Road Retrofit\3 - Photos\Construction Overview Presentation\Video--> HaggertAve_Final.MP4'' In LID facilities, a choker layer of ≥ 100 mm depth is recommended to prevent migration of finer filter media into the underlying storage reservoir aggregate. Similar to the storage reservoir material, this aggregate layer should be a washed 5 – 10 mm stone not containing any debris. Installation of aggregate choker layer should not be done when frozen. Follow the construction guidance shown above in the section “Storage reservoir”
For more information on the choker layer, see the page: [[Choker layer]]<br> "'INSERT VIDEO FROM HAGGERT AVE: \\Hqcvcfs01\cvc2\Watershed Management\Integrated Water Management Implementation\Fletchers Creek SNAP\Haggert Ave Road Retrofit\3 - Photos\Construction Photos\Site Visit_20201120\Riverstone Construction Haggert Ave Inlet_F.mp4'' 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 CSA standard A23.1-09. Key Inspection Points:<br> *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. [[File:20150618 114542.jpg|thumb|280px|right|Caption]]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.*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>
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. Installation of pre-treatment 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”*Curbing: Follow the guidance shown above in the section “Curbing”.*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.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.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.</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.P1160117.JPG|Installation of Jellyfish filter and sorbtive media vault at the IMAX bioswale project in Mississauga, ON.P1160121.JPG|Installation of Jellyfish filter and sorbtive media vault at the IMAX bioswale project in Mississauga, ON. </gallery> [[Category:Gallery]] Key Inspection Points:<br>*Verify that the correct pre-treatment device (jellyfish filter, vegetation, 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:<br>*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: [[Pretreatment]] and [[Pretreatment features]]. '''Soil Media / Filter Media'''<br> Bioretention can be constructed over any soil type, but hydrologic soil group A and B are best for achieving water balance objectives. Facilities designed to infiltrate water should be located on portions of the site with the highest infiltration rates. STEP has detailed construction guidance on soil amendments available on its [[https://sustainabletechnologies.ca/home/urban-runoff-green-infrastructure/healthy-soils/construction-specifications-for-implementing-compost-amended-planting-soil-in-ontario/ Construction Specifications for Implementing Compost Amended Planting Soil in Ontario]] webpage. These resources include specification details and a spreadsheet calculator for determining soil and amendment volumes. Construction Steps:#Apply soil media in 150-300 mm lifts until desired top elevation of bioretention, bioswale or rain garden area is achieved.#Apply soil media with slinger trucks when possible. This type of equipment will reduce the need to move soil media manually or by backhoe.#Thoroughly wet each lift before adding the next and wait until water has drained through the soil before adding the next lift.#If amending soils:**Stockpile native soils in designated areas.**Mix selected additives with native soils using a plumbus.**Sling soils into the LID feature whenever possible. Key Inspection Points:*When material arrives to the site: perform chain of custody, visual inspection and ribbon test to ensure that material meets design requirements.*Soil/filter media’s design parameters and assumptions should be confirmed through in-situ permeability testing (e.g., permeameter measurements to determine hydraulic conductivity). Results of permeability testing should be reviewed by the designer and, if required, changes to the LID design may be needed. See [[Testing]] for more information regarding testing procedures.*Ensure that soil media is being applied to the correct depth.*Ensure that the native soil and amended material are well blended.*Measure potentially compacted soils using a cone penetration test or a cone penetrometer.
Mistakes to Avoid: *Machine compaction - equipment should not be operated within the infiltration practice.*Soil material: Accepting material that does not meet design specifications and requirements.*Application: Applying the next lift without letting dry the previous lift of filter material.
→Backfill Granular and Pipes (SPC)
===Backfill Granular and Pipes (SPC)===
===Backfill Granular and Pipes (SPC)===
'''Storage Reservoir'''<br>
'''Storage Reservoir'''<br>
{{:Construction: storage reservoir}}
Construction steps:
'''Stone Choker Layer'''<br>
'''Stone Choker Layer'''<br>
{{:Construction: stone choker layer}}
'''Curbing'''<br>
'''Curbing'''<br>
{{:Construction: curbing}}
'''Pre-treatment and Inlet'''<br>
'''Pre-treatment and Inlet'''<br>
{{:Construction: pretreatment and inlet}}
Construction Steps:<br>
'''Soil Media and Amendment'''<br>
{{:Construction: soil media and amendment}}
===Finishing Grades: Inlet, Outlet, Biomedia, Plants (SPC)===
===Finishing Grades: Inlet, Outlet, Biomedia, Plants (SPC)===