Estimating the Cost and Carbon Impact of a Long Term Water Main Rehabilitation Strategy

Research has shown that some water utilities still have a strong preference for using "tried and true" open cut replacement techniques when rehabilitating water pipes in urban areas. Significant cost savings and reductions in carbon emissions can, however, be realised through the implementation of a strategy that incorporates trenchless rehabilitation techniques. This paper investigates the carbon emissions and financial implications of pipe rehabilitation strategies and analyses policies for three water utilities in Australia over a long-term planning horizon (30 years). When monetized, the carbon emissions from pipe rehabilitation are shown to be 0.1-0.2 % of the total revenue of a utility. However, given that direct and intangible cost reductions can be realised and there is a need to mitigate carbon emissions wherever possible, it is concluded that utilities should develop the capacity to use trenchless techniques in urban areas.