construction and refurbishment of earthen irrigation channel banks

13.2.6 When to use Life Cycle AnalysisA life cycle cost analysis can be of great advantage in making high cost, long lifedecisions. On the other hand, there may be little value in undertaking a life cyclecost analysis of short life (less than 10 years), low cost alternatives.A life-cycle analysis should always be considered when comparing alternatives withsignificantly different initial cost, life expectancy or ongoing costs. On the otherhand, a life-cycle-analysis will be of little value if the life expectancy, initial costand the ongoing costs are similar in the options being compared, or if the decisiondepends substantially on factors other than cost.Major emphasis at the investigation and design phases should be placed on theminimisation of life cycle costs. A poor design may result in:• expensive construction problems• high ongoing operation and maintenance costs• reduced asset life• expensive over or under specification of reliability, performance and service lifeDesigners faced with the comparison of more expensive, durable materials andlower cost shorter life span alternatives should asses life cycle costs.Care needs to be taken to avoid over analysing life-cycle-costs. The depth andaccuracy of analysis should be appropriate to the value of cost involved, thestrategic importance of the project and the time scales involved. There can be adanger of becoming immersed in excessive detail and a common sense approach isneeded.It is implicit in life-cycle analysis that the benefits for the different options are equalin each time interval. Where the options give rise to different potential benefitsthese must be considered in a broader economic evaluation process.13.3 Life Cycle Cost ConsiderationsLife cycle cost analysis requires a knowledge and understanding of all the costs associatedwith an asset. A channel typically goes through the following phases during its life cycle,from the identification of need through to disposal:• investigation• design• construction or acquisition• operation• maintenance• rehabilitation• replacement, and/or• disposalFigure 13-4 illustrates the typical distribution of costs over the life cycle of aninfrastructure asset.Construction and Refurbishment of Earthen Channel Banks August 2002 - Edition 1.0 13-6