Greening the city centre
Nigel Dunnett’s work at the Barbican in central London is a culmination of his interest in green roofs and sustainable planting.
Nigel Dunnett undoubtedly has the highest public profile of any of the academics at Sheffield. He is scarcely an international superstar but he is the person most likely to be recognised. Google him and you will find more than 90,000 results. (James Hitchmough, by contrast, with whom he works closely, had just under 12,000 when I looked.)
The two collaborated on the Olympic Park, but Nigel also has his own design area, having designed several show gardens at the Chelsea Flower Show which is firmly in the public domain. His job title at Sheffield is probably unique – professor of planting design and vegetation technology. He is also director of the university’s Green Roof Centre.
Whereas the Olympic Park was virtually a new site, since all its history had been obliterated in the restoration and clean up, he is now working in a very different environment, The Barbican in central London. This is a housing development built in the 1960s and 1970s, with a later (and listed) arts centre added. It seems as if half of London’s architects live there, so the stakes are high.
Nigel Dunnett describes his work as follows:
The transformation project at The Barbican is a pioneering example of climate-change adaptation in central London. It is a practical application of research programmes that I have undertaken in the department of landscape at the University of Sheffield for the past 15 years. These have focused on developing innovative green infrastructure for high-density urban development that integrates exciting and dramatic landscape planting that is cost-effective and multi-beneficial. As well as undertaking the fundamental research, my main activity concerns the promotion of the uptake of the results of that research. Much of my work is collaborative, with architects, landscape architects, local authorities, artists, and developers. Achieving real outcomes is not only very satisfying, but the collaborative approach is a fundamental part of my research process itself – in fact I have learnt far more about how to make these innovative approaches work through the interaction with real projects, than through the original experimental work.
For me, this is a circular process: the original research and its application to practice through collaboration and the establishment of real projects, is just the starting point. The real projects become objects of research in themselves – not just from a scientific viewpoint, but because they are in the public realm there is a wealth of social information too.
The uptake of these techniques has two major implications: a) a transformation in the appearance of many typical urban public realm contexts from resource-intensive vegetation to a sustainable alternative, with a radically different aesthetic appearance. The focus of my work is on urban podium landscapes and ‘landscapes above structure’ (extremely common in major cities: landscapes above structures e.g underground car parks; virtually all new London developments; “intensive green roofs’/roof gardens)” and b) implementation of green streets, rain gardens and other ‘ blue-green infrastructure’ applications – new-build and retro-fit – again with focus on the urban core.
The site of The Barbican transformation project is an urban podium landscape. It is a public space, used by visitors to what is Europe’s largest cultural and arts centre. But it is also the everyday landscape of the 4000 residents of the Barbican Estate.
In 2015, as a result of the need to re-waterproof the roof gardens, all of the existing planting was removed from the area. Previously, the landscape consisted of typical ‘municipal’ plantings of lawns, bedding plants, landscape shrubs and trees. However, because of a desire by the City of London Corporation to reduce or eliminate the need for automatic irrigation with potable water of the roof landscape, a completely different approach to the replanting was adopted. The new plantings consisted of a designed form of ‘steppe meadow’, which require very little in the way of irrigation, and which produces year-round visual interest, and greatly increased benefit to pollinating insects.
The project is directly linked to the research work I have undertaken on plant selection for green roofs and roof gardens. This work led to the establishment of ‘The Green Roof Centre’ at the University of Sheffield, and The Barbican plantings arose partly from the extensive trials and research work undertaken at the University of Sheffield, and partly as a result of experience from other applied projects. The planting style is very much in line with that which we used in the London Queen Elizabeth Olympic Park.
One of my wider objectives is to get the message out as widely as possible about the creative and aesthetic potential of ecologically inspired landscape design, that meets the twin challenges of climate change and increasing urbanisation. To that effect I have exhibited three Chelsea Flower Show gardens, all using this theme, and in 2015 I was invited by the BBC and the RHS to stage their flagship ‘Greening Grey Britain’ garden at the RHS Hampton Court Show. Alongside the fundamental research, and the collaborative work on real projects, this wider communication of these ideas to the public in general, forms an increasingly large part of my work.