April 2013: Thames Water recently submitted its 50,000 page (!) planning application for the development of the Thames Tideway Tunnel. It’s not surprisingly a big project …requiring the construction of a 15 mile tunnel to run 75 metres beneath the Thames riverbed through central London and would capture storm sewage from overflow points along the river. An online video on the project’s website can be viewed here.
The Tunnel has been designated a Nationally Significant Infrastructure Project (NSIP) and as such its application must be submitted to the National Infrastructure Planning Inspectorate. And it is on their website that an Energy and Carbon Footprint Report for the project can be found ( here – and directly downloadable here).
This report sets out an energy and carbon footprint assessment for the Thames Tideway Tunnel considering the CO2 equivalent emissions (CO2e) for both the construction and operation of the tunnel. The results are presented within Section 5 of the report, which provides details on the CO2e associated with construction materials, transport and logistics, worksite construction activities and operational energy demand. The assumptions which underpin the assessment, and the raw data which informs it, is also provided within the appendices of the report.
The report sets out that “the total carbon footprint, in the decarbonised scenario, of some 840,000 tCO2e (tonnes of carbon dioxide equivalent)the principal impact from the project is the GHG emissions caused by construction of the infrastructure, in particular embodied carbon in materials, being approximately 84% of the total emissions, with emissions from construction plant and machinery (construction worksite activities eg tunnel boring and emissions from plant and machinery) being around 10%of the total emissions. Emissions during the 120 year operational life of the tunnel represent approximately 2.5% of the total GHG emissions. The transport of excavated material and construction materials represents approximately 3.5% of the total carbon footprint of the project.” Much is placed on overall future electricity grid decarbonisation to help reduce the CO2 footprint of the project.