Changes

[[File:Life cycle costs RWH.PNG|thumb|center|400px|Construction and life cycle cost estimates for rainwater harvesting features features with partial infiltration (in 2016 $ figures) (TRCA, 2018)<ref name="example1" />.]]<br>

[[File:Life cycle costs RWH.PNG|thumb|center|400px|Construction and life cycle cost estimates for rainwater harvesting features features with partial infiltration (in 2016 $ figures) (TRCA, 2018)<ref name="example1" />.]]<br>

Estimates of the life cycle costs of inspection and maintenance have been produced using the latest version of the [[Cost analysis resources|LID Life Cycle Costing Tool]] for two design variations (nderground concrete cistern; and indoor plastic cistern systems) to assist stormwater infrastructure planners, designers and asset managers with planning and preparing budgets for potential LID features.

Estimates of the life cycle costs of inspection and maintenance have been produced using the latest version of the [[Cost analysis resources|LID Life Cycle Costing Tool]] for two design variations (underground concrete cistern; and indoor plastic cistern systems) to assist stormwater infrastructure planners, designers and asset managers with planning and preparing budgets for potential LID features.

Assumptions for the above costs and the following table below are based on the following:

Assumptions for the above costs and the following table below are based on the following:

*Capital costs included within the category of construction include those related to site assessment, and conceptual and detailed design related tasks such as borehole analysis and soil testing. All material, delivery, labour, equipment (rental, operation, operator), hauling and disposal costs are accounted for within the construction costs of the facility. Standard union costs were derived from the RSMeans database in 2010 and have been adjusted for 5 year inflation of 8.79% (2010 to June, 2015).  

*For rainwater cisterns it is assumed that no rehabilitation work will be needed to maintain acceptable storage and drainage performance over a 50 year period of operation (40 for plastic cisterns), given that pretreatment devices are in place and are being adequately maintained. The annual average maintenance cost value represents an average of routine maintenance tasks, as outlined in Table 7.28. All cost value estimates represent the NPV as the calculation takes into account average annual interest (2%) and discount (3%) rates over the evaluation time periods.

 

**Costs include overhead and inflation to represent contractor pricing. It was assumed the practice is part of a new development (i.e., not a retrofit), thereby excluding (de)mobilization costs unless a particular piece of equipment would not normally have been present at the site. Additionally, it was assumed that excavated soil associated with construction of the BMP would be reused elsewhere on site. Overhead costs were presumed to consist of construction management (4.5%), design (2.5%), small tools (0.5%), clean up (0.3%) and other (2.2%).  

**Costs include overhead and inflation to represent contractor pricing. It was assumed the practice is part of a new development (i.e., not a retrofit), thereby excluding (de)mobilization costs unless a particular piece of equipment would not normally have been present at the site. Additionally, it was assumed that excavated soil associated with construction of the BMP would be reused elsewhere on site. Overhead costs were presumed to consist of construction management (4.5%), design (2.5%), small tools (0.5%), clean up (0.3%) and other (2.2%).  

*For maintenance frequencies and requirements and the life span of each practice are based on both literature and practical experience. Life cycle and associated maintenance costs are evaluated over a 50 year timeframe, which is the typical period over which infrastructure decisions are made.

*For maintenance frequencies and requirements and the life span of each practice are based on both literature and practical experience. Life cycle and associated maintenance costs are evaluated over a 50 year timeframe, which is the typical period over which infrastructure decisions are made.