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| ===Designing with constraints=== | | ===Designing with constraints=== |
| {{textbox|Infiltration can still be optimized over 'tight' soils with infiltration rates ≤ 15 mm/hr: | | {{textbox|Infiltration can still be optimized over 'tight' soils with infiltration rates ≤ 15 mm/hr: |
| *[[Bioretention: Internal water storage |Bioretention with internal water storage]] | | *See [[Underdrains]] for [[Bioretention]] and [[tree pits]], and |
| *[[Bioretention:_Partial_infiltration|Partially infiltrating bioretention]]
| | *Results from STEP studies over [[low permeability soils]] |
| See also [[Low permeability soils]]
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| }} | | }} |
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| {{textbox|Where infiltration is impossible, LID design alternatives exist which can still capture and retain stormwater: | | {{textbox|Where infiltration is impossible, LID design alternatives exist which can still capture and retain stormwater: |
| *[[Biofilters]] | | *[[Stormwater planters]] |
| *[[Rainwater harvesting]] | | *[[Rainwater harvesting]] |
| *[[Green roofs]] | | *[[Green roofs]] |
| | *[[Blue roofs]] |
| }} | | }} |
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| ==Planning== | | ==Planning== |
| | | ===Hydrogeology=== |
| <h3>Hydrogeology</h3>
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| The Conservation Authorities Geoscience Group has prepared a guidance document which attempts to standardize the hydrogeological study requirements for development applications made to Conservation Authorities. It is a helpful guide for all low impact development applications which include infiltration. It is provided with the caveat that not all sections or content are necessary or appropriate for every case. Pre-consultation with your Conservation Authority and municipality is strongly recommended in all cases. | | The Conservation Authorities Geoscience Group has prepared a guidance document which attempts to standardize the hydrogeological study requirements for development applications made to Conservation Authorities. It is a helpful guide for all low impact development applications which include infiltration. It is provided with the caveat that not all sections or content are necessary or appropriate for every case. Pre-consultation with your Conservation Authority and municipality is strongly recommended in all cases. |
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| '''[http://www.lsrca.on.ca/Shared%20Documents/permits/hydrogeological%20_guidelines.pdf?pdf=Hydrogeological-Guidelines Hydrogeological Assessment Submissions Conservation Authority Guidelines for Development Applications]''' | | '''[http://www.lsrca.on.ca/Shared%20Documents/permits/hydrogeological%20_guidelines.pdf?pdf=Hydrogeological-Guidelines Hydrogeological Assessment Submissions Conservation Authority Guidelines for Development Applications]''' |
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| | | ==Beginning a BMP design?== |
| NEW CONTENT HERE?
| | See [[Design infiltration rates]] |
| Needs advice on setbacks adding.
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| <h4>Soil infiltration rate</h4>
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| [[Infiltration: Testing|Infiltration tests]] must be undertaken at the location, depth and with a head of water that replicates the proposed design. | |
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| {|class="wikitable"
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| |+ Suggested safety factors to be applied to measured percolation rate when designing infiltration facilities
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| |-
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| !rowspan = "2"|Catchment area
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| !colspan="3"|Consequence of failure
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| |-
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| !No damage or inconvenience
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| !Minor damage or inconvenience to external structures (e.g. ponding in parking lot)
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| !Significant damage to buildings or infrastructure (e.g. flooding damage)
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| |-
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| |<100 m<sup>2</sup>||1.5||2||10
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| |-
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| |100 - 1000 m<sup>2</sup>||1.5||3||10
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| |}
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| [[category:Infiltration]] | | [[category:Infiltration]] |