The Greener Grangetown project site covers 12 Victorian streets and 550 properties. Prior to the scheme, surface water entered the combined sewer network and was then pumped a total of 8 miles before being treated and discharged into the Severn Estuary. The concept for Greener Grangetown developed from the original aim of removing surface water that entered Dr Cymru Welsh Waters combined sewer network. This would reduce operational costs for the company and provide resilience against the impacts of climate change and urbanisation by providing extra capacity in the combined sewer system.

A delivery partnership of Cardiff Council, Dr Cymru Welsh Water and Natural Resources Wales allowed the wider benefits of the SuDS project to be identified and maximised. A feasibility study undertaken in 2013 by Arup identified that the public realm, environment, and transport infrastructure could be transformed as part of the project, with a calculated annual benefit of 381,760 using various cost databases available at the time. The feasibility study provided a business case for the project and helped secure funding by identifying and monetising the benefit to each of the partnership organisations.

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