Estimation and Evaluation of Greenhouse Gas Emissions during the Life-Cycle of Wastewater Pipelines: Case Study of Tehran, Iran

Climate change occasioned by the accumulation of greenhouse gases (GHGs) is now widely accepted as an issue which mankind needs to address. The starting point is necessarily the determination of all the sources of emissions during the life-cycles of the studied components. Post-calculation, the results ought to be presented to decision-makers in a clear manner so as to provide the basis on which corrective actions could be considered. This paper calculates the GHGs emissions during the life-cycle of wastewater pipelines and introduces a different approach to communicate information about GHGs released, to decision-makers. Different diameters of concrete and high-density polyethylene (HDPE) wastewater pipes are compared in a case study. Results show that the total CO2-equivalent (CO2-eq) emissions attributed to concrete pipes are greater than HDPE pipes. Hence, the equivalent bio-productive area of forest required to sequester the CO2 (the major GHG) and its corresponding costs will be greater for the former.