Methodology for determining life-cycle environmental impacts due to material and energy flows in wastewater pipeline networks: A case study of Oslo (Norway)

Abstract

Any saturated urban wastewater pipeline network has an ageing mix of pipelines of different lengths, diameters and materials of construction. Each of these pipe-lengths has its own life-cycle which encompasses the material production and pipe fabrication, installation, operation and maintenance during the use phase, rehabilitation and repair and finally retirement from service. An analysis of the inflows of materials and energy into the network and the corresponding outflows, facilitates the determination of the environmental impacts associated with the life-cycle stages of the pipeline network, and an examination of how the contributions of each of these phases to the whole, changes as the network ages and progresses towards saturation. The forecast of the future flows of materials which again, is highly interlinked with the historic flows provides insight into the likely future environmental impacts. The authors, in this paper, present a general methodology which can be applied with some tailor-making, to the analysis of any wastewater pipeline network in general. The methodology is then applied to the pipeline network in the city of Oslo, and the results thereof presented towards the end of the paper.

Assessment of Environmental Impacts of an Aging and Stagnating Water Supply Pipeline Network

“…Data on rehabilitation were obtained upon request from Oslo VAV. The foremost rehabilitation method, as in the case of wastewater pipelines (Venkatesh et al 2009), has been the cast‐in‐place‐pipe (CIPP) method, where a thin polymeric coating is applied to the inner circumference of the pipeline, effectively isolating it from the flow and subjecting only the surface of the polymeric coating to the direct radial stresses imposed by the flowing water. Of course, the pipe material surrounding the coating serves as an envelope to this “new pipe” cast in place inside it.…”

“…The goal of the LCA is both to test the methodology developed and published by Venkatesh and colleagues (2011) on water pipeline systems and Venkatesh and colleagues (2009) on wastewater pipeline systems, and to obtain results for the environmental impact related to the flows that are mobilized by the pipeline network stock over time. The function of the water pipeline network is to distribute potable water from its sources, via treatment plants, to the users in Oslo.…”

“…Then, the results from the material and energy flow analyses are presented and the subsequent LCA is carried out. The results obtained for the water pipeline network in this article are compared with those for the wastewater pipeline network in Oslo, examined by Venkatesh and colleagues (2011).…”

Exploring urban mines: pipe length and material stocks in urban water and wastewater networks

“…The dominating material for wastewater networks is concrete, which contribute approximately 85 % to the total mass. Venkatesh (2011) shows that for Oslo, the total length of pipes in all diameter classes has saturated, and that the per-capita length is falling due to the growing population.…”

Productivity growth of wastewater treatment plants – accounting for environmental impacts: a Malmquist-Luenberger index approach

“…GHG emissions are responsible for climate change which is a significant environmental global problem frequently assessed in the life-cycle assessment of WWTPs (Gallego et al, 2008;Rodríguez-García et al, 2011;Venkatesh et al, 2011). The first was the emission of GHG, expressed in the kg of equivalent CO 2 (CO 2 )(b 1 ).…”