London’s existing sewer system dates back to Victorian era, when Sir Joseph Bazalgette designed an innovative combined sewer, capable of managing both rainfall and foul sewage from the capital. London’s population at the time was 2 million people, however through foresight and good design the Victorian system was designed to cater for 4 million. London now has a daily population of over 8 million people, and the existing system regularly discharges untreated sewage into the tidal River Thames.
The Thames Tideway Tunnel is London’s major new sewer which is being built to protect the tidal River Thames from pollution and ensure that the Capital complies with the Urban Waste Water Treatment Directive. Once completed, the 25km ‘super sewer’ will be one of the deepest tunnels in London, and will store and transfer tens of millions of tonnes of untreated sewage each year to Beckton Sewage Treatment works, where the material will be used to generate energy.
Sustainability is at the heart of the project, which is designed to address the challenges faced by population growth and climate change. The project is supporting a number of UN Sustainable Development Goals, including demonstrating Industry Innovation within Infrastructure Sector (Goal SD9) and Responsible Consumption and Production (Goal SD12). In pursuing these Sustainable Development Goals, the project team engaged with the Building Research Establishment to develop and pilot the emerging BREEAM Infrastructure standards. Tideway has been one of a handful of projects to have trialled the new standard.
As experienced sustainability and BREEAM consultants, Envision has been supporting the project to progress the Strategic Assessment Stage against BREEAM Infrastructure, by undertaking a retrospective analysis of the project. Through the extensive review, Tideway has been awarded a Strategic Assessment Certificate demonstrating a Very Good rating. Although the BREEAM pilot study is now complete, the exercise has helped to inform the emerging version of CEEQUAL. Envision staff have been seconded by the BRE to assist with finalising the new standard which is due for industry release in May 2019.
Through the Tideway Green Bond Framework the project will continue to assess sustainability delivery of the project. It is committed to annual reporting against the 15 Sustainable Development Objectives set out in its Legacy Plan and has committed to continued dialogue with the BRE as it develops the new infrastructure standard. Envision and Tideway will therefore continue to collaborate with BRE sharing knowledge, innovation and best practice experience for the benefit of the whole infrastructure sector.

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