Grey to Green — Sheffield's Retrofit SuDS Scheme Turning a Dual Carriageway into Rain Gardens (UK)
United Kingdom
Sheffield turned a redundant dual carriageway into the UK's largest retrofit SuDS scheme (2014-2022): swales cut peak flow up to …
Singapore · Singapore · See the Singapore profile · See the Singapore profile
Evidence: Descriptive / self-reported Top 27% 53/100 · Ask Evidence Copilot about this practice
PUB and NParks turned a 2.7 km concrete canal carrying the Kallang River into a 3 km naturalised, meandering river through Bishan–Ang Mo Kio Park (2007–2012), widened up to 5x and doubling as flood storage; PUB reports a 30% rise in biodiversity since completion.
Singapore's national water agency PUB, together with the National Parks Board (NParks), redeveloped Bishan–Ang Mo Kio Park between 2007 and 2012 under the Active, Beautiful, Clean Waters (ABC Waters) Programme. The project transformed a straight, 2.7-kilometre concrete drainage canal carrying the upper Kallang River into a naturalised, meandering waterway roughly 3 kilometres long running through the park.
The new channel was widened up to five times its original width and designed on a flood-plain concept: during dry weather the river flows through a narrow central stream, and during storms the surrounding parkland floods to convey stormwater safely downstream before draining back within hours. About 10 bio-engineering soil-stabilisation techniques, new to Singapore at the time, were tested over 11 months before construction.
PUB reports the surrounding biodiversity has increased by 30% since completion, with otters, egrets and dragonfly and damselfly species now regularly recorded. The SGD 76.7 million (USD 56.3 million) project was designed by Ramboll Studio Dreiseitl with CH2M Hill Singapore and has won several awards, including the World Architecture Festival's 2012 Landscape of the Year and a 2016 ASLA Professional Honor Award.
The 30% biodiversity increase is PUB's own figure; no independently peer-reviewed monitoring study of species counts was located, and no carbon or fire-related outcome data exists for the site. The flood-conveyance function, by contrast, is corroborated independently by both PUB's engineering documentation and C40 Cities' case study.
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United Kingdom
Sheffield turned a redundant dual carriageway into the UK's largest retrofit SuDS scheme (2014-2022): swales cut peak flow up to …
Rwanda
Kigali is rehabilitating five degraded urban wetlands (491 ha: Gikondo, Rwampara, Nyabugogo Lower, Kibumba, Rugenge-Rwintare) into flood-control eco-parks under a …
India
Pallikaranai Marsh, a 1,247-hectare Ramsar wetland (designated 2022) in Chennai, buffers monsoon floods for the city's south and hosts 120+ …
Singapore
Singapore's national tree-planting programme, run by NParks under the Green Plan 2030, had planted over 832,000 of a targeted 1 …
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