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Line 23: − + − − − * The Tool assumes an in-line system. − * The Tool assumed curb-and-gutter around the circumference of the facility with curb-cut inlets every 6 to 0.5 meter squared and stone splash pads. − * The greater the slope, the more check dams placed by the Tool. The unit cost for check dams is for the amount of material required, not number of dams. − * If configuration include driveway (2 laned), a culvert pipe connects the enhanced grass swale (EGS) and an extra 0.1m of gravel is added beneath culvert. − * Swales which cross multiple driveways or smaller driveways can be accounted for by multiplying or dividing these costs in the "Additional Costs" cells. Line 42:
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→Full Infiltration
Design and operation and maintenance program assumptions used to generate cost estimates are based on tool default values and the following STEP recommendations:
Design and operation and maintenance program assumptions used to generate cost estimates are based on tool default values and the following STEP recommendations:
* Native soil infiltration rate for Full Infiltration Design scenario was assumed to be 20 mm/h, and a safety factor of 2.5 was applied to calculate the design infiltration rate.
* Native soil infiltration rate for Full Infiltration Design scenario was assumed to be 20 mm/h, and a safety factor of 2.5 was applied to calculate the design infiltration rate.
* Operation and maintenance (O&M) cost estimates assume annual inspections, removal of trash and debris twice a year, removal of sediment from outlet catch basin annually, and removal of weeds twice a year. Verification inspections are included every 5 years to confirm adequate maintenance, and every 15 years to confirm adequate drainage performance through in-situ surface infiltration rate testing.
* Ditch inlet catch basin structure located at furthest downgradient end, with connection to storm sewer pipe, included as the outlet.
* Operation and maintenance (O&M) cost estimates assume annual inspections, removal of trash and debris twice a year, removal of sediment from curb inlets and outlet catch basin annually, and removal of weeds twice a year. Verification inspections are included every 5 years to confirm adequate maintenance, and every 15 years to confirm adequate drainage performance through in-situ surface infiltration rate testing.
* Impervious drainage area to pervious swale footprint area of 10:1 (tool default value).
* Impervious drainage area to pervious swale footprint area of 10:1 (tool default value).
* Designed with a trapezoidal cross section with a top width of 4.75 m, bottom width of 0.75 m, and 2.5:1 side slopes (tool default values).
* Designed with a trapezoidal cross section with a top width of 4.75 m, bottom width of 0.75 m, and 2.5:1 side slopes (tool default values).
===Notes===
===Notes===
* Designs include [[pretreatment]] through stone diaphragms at [[Curb cuts|curb inlets]].
* Design includes [[pretreatment]] through stone diaphragms at [[Curb cuts|curb inlets]].
* Operation and maintenance cost estimates assume rehabilitation of the swale surface is required after 25 years of operation.
* Operation and maintenance cost estimates assume rehabilitation of the swale surface is required after 25 years of operation.
* The tool calculates costs for new (greenfield) development contexts and includes costs for contractor overhead and profit, material, delivery, labour, equipment (rental, operating and operator costs), hauling and disposal.
* The tool calculates costs for new (greenfield) development contexts and includes costs for contractor overhead and profit, material, delivery, labour, equipment (rental, operating and operator costs), hauling and disposal.
** Land value and equipment mobilization and demobilization costs are not included, assuming BMP construction is part of overall development site construction.
** Land value and equipment mobilization and demobilization costs are not included, assuming BMP construction is part of overall development site construction.
==Construction Costs==
==Construction Costs==
[[File:Construction Breakdown EnhancedSwales Full Infil.PNG|thumb|center|950px|'''Construction Costs Per Unit Drainage Area (CAD$/m<sup>2</sup>) - Full Infiltration Design, 25 mm Treatment''']]
[[File:Construction Breakdown EnhancedSwales Full Infil 2023.PNG|thumb|center|950px|'''Construction Costs Per Unit Drainage Area (CAD$/m<sup>2</sup>) - Full Infiltration Design, 25 mm Treatment''']]
Above you can find a cost breakdown of a 1000m<sup>2</sup> LID configuration:<br>
Above you can find a breakdown of construction costs by expense type for a 200 m<sup>2</sup> surface area facility (I:P area ratio of 10:1):<br>
#[[Enhanced swales|Enhanced Swales: Full Infiltration]]
#[[Enhanced swales|Enhanced Swales: Full Infiltration]]
Material & Installation expenses represent the largest portion of total construction costs (50%).
Material & Installation expenses represent the largest portion of total construction costs (55%).
==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 [[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 39% of total life cycle costs over the 25-year evaluation period, and increase to 54% of total life cycle costs over the 50-year period, due to swale surface rehabilitation costs assumed to be required after 25 years of operation.
===25-Year life cycle cost break down===
===25-Year life cycle cost break down===
[[File:25yr LCCT EnhancedSwales Full Infil.PNG|thumb|center|900px|'''Enhanced Swales: Full Infiltration''']]
[[File:25yr LCCT EnhancedSwales Full Infil 2023.PNG|thumb|center|900px|'''Enhanced 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|'''Enhanced Swales: Full Infiltration''']]
[[File:50yr LCCT EnhancedSwales Full Infil 2023.PNG|thumb|center|900px|'''Enhanced 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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==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 estimate over the 50 year evaluation period for the [[Enhanced swale]] Full Infiltration design configuration is ($65,021.40), making it one of the cheapest LID BMP options.<br>
===Full Infiltration===
===Full Infiltration===
[[File:CVC Office, Grass Swale.JPG|500px|thumb|Enhanced Grass [[swale]] in CVC headquarters parking lot, Mississauga ON.]]
[[File:CVC Office, Grass Swale.JPG|650px|thumb|Enhanced Grass [[swale]] in CVC headquarters parking lot, Mississauga ON.]]
[[File:Design Table EnhancedSwales Full Infil.PNG|700px]]<br>
[[File:Design Table EnhancedSwales Full Infil 2023.PNG|700px]]<br>
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