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==Life Cycle Costs==
==Life Cycle Costs==
Below are capital and life cycle cost estimates for the [[Enhanced swales]] Full Infiltration configuration over 25- and 50-year time periods. The estimates of maintenance and rehabilitation (life cycle) costs represent net present values. Operation and maintenance costs are predicted to represent 45% of total life cycle costs over the 25-year evaluation period, and increase to 59% of total life cycle costs over the 50-year period, due to increased levels of litter removal, watering (establishment period - years 1 & 2 / annually and / drought watering) cleaning out and vacuuming of the catchbasin, mowing, replacement of sod, weeding and pruning of the BMP's planted [[vegetation]].
Below are capital and life cycle cost estimates for the [[Green roofs]] with a No Infiltration configuration over 25- and 50-year time periods. The estimates of maintenance and rehabilitation (life cycle) costs represent net present values. Operation and maintenance costs are predicted to represent 4% of total life cycle costs over the 25-year evaluation period, and increase to only 6% of total life cycle costs over the 50-year period. Maintenance costs associated that make up a smaller percentage of total capital include, litter removal, watering (establishment period - years 1 & 2 / annually and / drought watering), weeding and pruning of the BMP's planted [[vegetation]], plant replacement starting in tear 2, green roof irrigation line testing, membrane leak detection testing and repair of the membrane starting in Year 10.


===25-Year life cycle cost break down===
===25-Year life cycle cost break down===


[[File:25yr LCCT EnhancedSwales Full Infil.PNG|thumb|center|900px|'''Enhances Swales: Full Infiltration''']]
[[File:25yr LCCT GreenRoof No Infil.PNG|thumb|center|900px|'''Enhances Swales: Full Infiltration''']]


<small>'''Note:''' Click on each image to enlarge to view associated life cycle cost estimate.</small><br>
<small>'''Note:''' Click on each image to enlarge to view associated life cycle cost estimate.</small><br>
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===50-Year life cycle cost break down===
===50-Year life cycle cost break down===


[[File:50yr LCCT EnhancedSwales Full Infil.PNG|thumb|center|900px|'''Enhances Swales: Full Infiltration''']]
[[File:50yr LCCT GreenRoof No Infil.PNG|thumb|center|900px|'''Enhances Swales: Full Infiltration''']]


<small>'''Note:''' Click on each image to enlarge to view associated life cycle cost estimate.</small><br>
<small>'''Note:''' Click on each image to enlarge to view associated life cycle cost estimate.</small><br>


==Cost Summary Tables==
==Cost Summary Tables==
Total life cycle cost estimates for the [[Enhanced swale]] Full Infiltration design configuration is ($23,451.36), makign it one of the cheapest LID BMP options.<br>
Total life cycle cost estimates for the [[Green roofs]] No Infiltration design configuration is ($740,943.00), making it one of the most expensive LID BMP options. This is due to the costs of expensive components such as, waterproof membrane and flashing, roof insulation required, drainage layer and filter cloth, growing medium, the plants themselves and crane requirements for construction.<br>


It is notable that a sensitivity analysis was conducted in 2019 to compare construction cost estimates generated by the tool to actual costs of implemented projects. '''The analysis found that tool estimates were typically within ±14% of actual construction costs'''<ref>Credit Vally Conservation (CVC). 2019. Life-cycle costing tool 2019 update: sensitivity analysis. Credit Valley Conservation, Mississauga, Ontario. https://sustainabletechnologies.ca/app/uploads/2020/04/LCCT-Sensitivity-Analysis_March2020.pdf</ref>
It is notable that a sensitivity analysis was conducted in 2019 to compare construction cost estimates generated by the tool to actual costs of implemented projects. '''The analysis found that tool estimates were typically within ±14% of actual construction costs'''<ref>Credit Vally Conservation (CVC). 2019. Life-cycle costing tool 2019 update: sensitivity analysis. Credit Valley Conservation, Mississauga, Ontario. https://sustainabletechnologies.ca/app/uploads/2020/04/LCCT-Sensitivity-Analysis_March2020.pdf</ref>


===Full Infiltration===
===No Infiltration===
[[File:CVC Office, Grass Swale.JPG|500px|thumb|Enhanced Grass [[swale]] in CVC headquarters parking lot, Mississauga ON.]]
[[File:Layers green roof.PNG|thumb|right|500px|Generalized cross-section view of a green roof showing key components and common layers that make up this LID BMP (TRCA, 2018).<ref name="example1"> TRCA. 2018. Fact Sheet - Inspection and Maintenance of Stormwater Best Management Practices: Green Roofs. https://sustainabletechnologies.ca/app/uploads/2018/02/Green-Roofs-Fact-Sheet.pdf</ref>]]


[[File:Design Table EnhancedSwales Full Infil.PNG|700px]]<br>
[[File:Design Table GreenRoof No Infil.PNG|700px]]<br>
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==References==
==References==

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