Changes

[[File:construction process.jpg|400px|thumb|right|The five-step construction process for sub-surface and ground-level LIDs.]]

[[File:construction process.jpg|400px|thumb|right|The five-step construction process for sub-surface and ground-level LIDs.]]

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==Overview==

==Overview==

This section gives guidance for project managers, engineers, and contractors on the pre-construction steps required for successful construction of sub-surface and ground-level LID practices.  

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]]. It was developed for project managers, engineers, and contractors on the pre-construction steps required for successful construction of sub-surface and ground-level LID practices.  

==Design verification and site walk-through==

==Design verification and site walk-through==

===Minimum contractor requirements===

===Minimum contractor requirements===

Many contractors are unfamiliar with building LID practices, so project managers should consider minimum contractor requirements. Consider mandating contractor training, attendance at pre-bid meetings, LID project references, and bid bond insurance as prerequisites.

Many contractors are unfamiliar with building LID practices. Consider mandating contractor training, attendance at pre-bid meetings, LID project references, and bid bond insurance as prerequisites.

==Communication, inspection plan, and utilities coordination==

==Communication, inspection plan, and utilities coordination==

===Inspection plan===

===Inspection plan===

The [[inspection and maintenance]] page gives detailed guidance on how to conduct construction inspections for LID practices. Generally, construction inspections should be continuous as the work progresses. If this isn’t possible, critical inspection points are:

The [[inspection and maintenance]] page gives detailed guidance on how to conduct construction inspections for LID practices. Generally, construction inspections should be continuous as the work progresses. If this isn’t possible, critical inspection points are:

==Erosion and sediment control measures==

==Erosion and sediment control measures==

[[File:ESC perpendicular grooves.jpg|400px|thumb|right|Grooves perpendicular to the grade help prevent the development of rills. '''If left unchecked, rills can develop into gullies.''' (Photo source: CVC)]]

[[File:ESC perpendicular grooves.jpg|400px|thumb|right|Grooves perpendicular to the grade help prevent the development of rills. (Photo source: CVC, 2022)]]

STEP’s [https://sustainabletechnologies.ca/app/uploads/2020/01/ESC-Guide-for-Urban-Construction_FINAL.pdf Erosion and Sediment Control Guide] contains detailed guidance on the design, installation, inspection, maintenance, and decommissioning of ESC measures. This section gives practical advice on structural and non-structural ESC for contractors, inspectors, and those who are new to construction and ESC practices.

STEP's [https://sustainabletechnologies.ca/home/urban-runoff-green-infrastructure/healthy-soils/construction-specifications-for-implementing-compost-amended-planting-soil-in-ontario/ Erosion and Sediment Control Guide for Urban Construction]]<ref> STEP. 2019. Erosion and Sediment Control Guide for Urban Construction. https://sustainabletechnologies.ca/home/urban-runoff-green-infrastructure/healthy-soils/construction-specifications-for-implementing-compost-amended-planting-soil-in-ontario/</ref> contains detailed guidance on the design, installation, inspection, maintenance, and decommissioning of ESC measures. This section gives practical advice on structural and non-structural ESC for contractors, inspectors, and those who are new to construction and ESC practices.

Establish required perimeter controls, including erosion and sediment control (ESC) measures, prior to construction and adjust accordingly during construction. ESC measures come in two basic types: structural ESC, which slows and holds runoff from the disturbed area, dissipating erosive forces, promoting ponding, and allowing suspended particles to settle out; and non-structural ESC, which primarily minimizes the exposure time of stripped soils.  

Establish required perimeter controls, including erosion and sediment control (ESC) measures, prior to construction and adjust accordingly during construction. ESC measures come in two basic types: structural ESC, which slows and holds runoff from the disturbed area, dissipating erosive forces, promoting ponding, and allowing suspended particles to settle out; and non-structural ESC, which primarily minimizes the exposure time of stripped soils.  

[[File:ESC sacrificial fabric.png|300px|thumb|center|]]

[[File:ESC sacrificial fabric.png|300px|thumb|center|]]

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[[File:ESC premature removal.jpg|300px|thumb|center|ESC measures at this bioretention feature were removed before construction in its drainage was complete, allowing sediment into it.]]

[[File:ESC premature removal.jpg|300px|thumb|center|ESC measures at this bioretention feature were removed before construction in its drainage was complete, allowing sediment into it.(Photo Source: CVC)]]

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==Erosion and sediment control inspection and maintenance==

==Erosion and sediment control inspection and maintenance==

ESC measures require ongoing attention to ensure integrity and performance. ESC inspections should take place, at minimum, during installation, after rainfall events, and at the critical inspection points discussed in the [[Pre-construction: communication, inspection plan, and utilities coordination (section)]].

ESC measures require ongoing attention to ensure integrity and performance. ESC inspections should take place, at minimum, during installation, after rainfall events, and at the critical inspection points discussed in the [[Pre-construction#Communication, inspection plan, and utilities coordination|Pre-construction: Communication, inspection plan, and utilities coordination]]

At these inspections, keep an eye out for accumulated sediment, worn materials, compliance with the project's staging plan, and potential failure points.

At these inspections, keep an eye out for accumulated sediment, worn materials, compliance with the project's staging plan, and potential failure points.

In tandem with installation of ESC measures, setting up access and staging areas is one of the first steps in any construction project. Perimeter controls such as construction fencing are often combined with silt fencing. Safety fencing may be needed to restrict public access to the site, especially if the site sees lots of pedestrian traffic. Together, construction fencing and structural ESC measures should demarcate:  

In tandem with installation of ESC measures, setting up access and staging areas is one of the first steps in any construction project. Perimeter controls such as construction fencing are often combined with silt fencing. Safety fencing may be needed to restrict public access to the site, especially if the site sees lots of pedestrian traffic. Together, construction fencing and structural ESC measures should demarcate:  

*the limits of construction  

*limits of construction  

*heavy equipment routes

*heavy equipment routes

*equipment and material storage areas  

*equipment and material storage areas  

'''Construction steps'''

'''Construction steps'''

#Install perimeter fencing/silt fence in alignment with design drawings and ESC plan.

#Install perimeter fencing/sediment fence in alignment with design drawings and ESC plan.

#Demarcate staging and access points with fencing or surface markings in alignment with design drawings.

#Demarcate staging and access points with fencing or surface markings in alignment with design drawings.

'''Key inspection points'''

'''Key inspection points'''

*Ensure perimeter fencing and access/staging areas are in alignment with design drawings.

*Ensure perimeter fencing and access/staging areas are in alignment with design drawings.

'''Mistakes to avoid'''

'''Mistakes to avoid'''

#Departing from the plan to stage and limit access points, material storage areas, and equipment storage areas

*Departing from the plan to stage and limit access points, material storage areas, and equipment storage areas

#Installing inadequate perimeter controls, e.g. inadequate sediment fencing or construction fencing

*Installing inadequate perimeter controls, e.g. inadequate sediment fencing or construction fencing