Understanding the ‘values’ of urban rivers

Why is it that the private sector is not driving forward projects to open up urban rivers in cities? There are clearly so many benefits, and judging by the praise given to the Matilda St project in Sheffield, these seem to outweigh the costs.

This recent talk given at an EU Presidency in Estonia tackles these and other questions about ‘nature-based solutions’. It sums up a paper written with old colleagues/friends, based on 10 years of project work coordinated from Sheffield. Sadly the paper isn’t open access, but copies can be requested here.
Multiple values of nature based solutions
In short, the valuable benefits of new green corridors and riverside parkways can’t/shouldn’t be enclosed. Private developers have to cover their costs and make a profit (how much?). If the benefits can’t be captured, they can’t be used to offset the costs. But cities and citizens can – and do – benefit greatly from the investment. So, our take on it is that this is a market failure, i.e. missed opportunity. Cities, NGOs and citizens can work together to drive forward these great projects, but only with public support. And that’s Political.

Images are courtesy of the ursula project and with thanks to Ed Morgan, Lewis Gill and Laurence Pattacini. No prizes for guessing the location, what do you think this is, Christmas? holly

OK, I’m no Owls fan, but…

…that still doesn’t explain why this image of ‘Sheffield river’ is so disappointing, does it?

A recent search for info on the lesser known rivers of the city (Carr Brook, Jervis Lumb, Blackburn Brook etc) took me here:

Folks do some pretty extreme things to gain a bit of space and land.

After a break, and feeling energised, it is probably about time to start uploading some more intriguing examples.

Putting the Sheaf back in Sheffield – a small but extremely important stretch of urban river for daylighting

Sheffield gets its name from the Sheaf-Field, the location next to the old Norman Castle where the River Sheaf joins the Don. It was an important strategic stronghold as well as a meeting place and market location in medieval times. The site has been hidden and buried for around a century.

Plans have been developed for an important project to deculvert the river in this historically critical location.


The site lays at the heart of Sheffield and is one of the key actions in the Sheffield Waterways Strategy. It has been a shared ambition of many partners working together for several years.

With this in mind I rooted out this image of the site, exploring urban forms for a daylighting scheme here, from 2009! The image was drawn up in sketchup but based on cross-sections and topographical data from a hydraulic (river) model to investigate flood risk management scenarios. The historic local pubs were kept in the picture, of course…

Let’s hope the project gets funded.


Deculverting image Copyright Tom Wild

Oh, by the way, the curly pig-tail structure was the old car ramp access to the castle market (both now gone), right over the ‘Sheaf Field’.


Deculverting Sheffield’s Porter Brook – City Centre

I’ve promised various people that I would  post up some before and after pictures to show the impact of this city centre project, so here we go.

Precise fixed point photos weren’t possible due to site access issues and changes in land levels, but these are as close as possible, and give a good idea of the changes over time. Slide 5 shows the site from above, and the position and direction of the following images, as well as details of the feasibility study.

I’ll take further photos from the same spot so that we can keep an eye on he river regeneration process. By the way, the big redbrick building is Matilda Works, now part of the UTC. Amazing spot. Congratulations to all involved for an excellent scheme (too many to note here).

1. 2011.

Deculverting image copright Tom Wild - 1

2. 2012a.

Deculverting image copright Tom Wild - 2

3. 2012b.

Deculverting image copright Tom Wild - 3

4. 2016.

Deculverting image copright Tom Wild - 4

5. Feasibility study by Sheffield City Council for South Yorkshire Forest Partnership. With thanks to the Environment Agency and Interreg North Sea Region Programme for funding.


Deculverting image copright Tom Wild


Urban Hybrids, daylighting & pigeons (not hybrid pigeons though)

Recent visits to a daylighted brook set me thinking about regeneration, architecture and nature, and recalling a paper I’d read years ago, which to be honest I didn’t really understand at the time. Strange how some writings have a habit of lying dormant in the mind, in wait for the right opportunity to resurface. This sight of pigeons roosting in the sockets that previously acted as the footings for steel joists, providing the support for an old culvert roof, brought to mind a piece of work by architect Xiang Ren on hybridisation.

Deculverting image copyright Tom Wild

Sadly, the paper can’t be found online anymore, but I found a few extracts, as follows. In his design research proposal ‘A hybrid building for place-specific resilience… blue loop hybrids’, Ren (undated) poses the question: ‘”o what extent can urban architecture evolve into a more resilient form – the potential harmony and resilience between nature and the artificial”.

Xiang Ren notes that the term ‘hybridity’ was first put forward in relation to architecture as ‘an effort to provoke thoughts towards the spatial and programmatic renewal of American cities’ (Holl, 1980), and as a typology for mixed-used buildings… and an architectural morphology. He goes on to note that an important part of urban hybridization emerged by the coupling of landscape design and city making: ‘landscape urbanism and ecological urbanism’ (Leatherbarrow, 2011).

For me when this really gets interesting is the point at which the individual structures are considered in relation to the wider network of infrastructures – including blue-green infrastructure: ‘urban artefacts… as a hybrid of artificial ecology form part of the ‘patch-corridor-matrix’ model (Forman, 1995) for resilience, spatially meshing natural process and human activities on land, and drawing on the perspective of ‘cities of evolution’ first addressed by biologist Patrick Geddes (Geddes, 1915).

In other words, what is the relation between a ‘site’ for urban wildlife, and the wider ecological network? How important is one link in the chain? Does its value depend solely on its context – i.e. the state of the rest of the network? Have we gone too far in thinking that biodiversity must be considered within these networks or catchments? Or does that just reinforce a status quo of preservation of ‘natural’ (for natural, read rural) sites as being more valuable than the urban? I like this sentiment in Ren’s paper: What new hybrid structure can evolve an ecological catalyst to activate a new type of wildlife habitat for the place-specific?  How can urban nature conservation move forwards without such catalysts?

Worth noting that Geddes was a contemporary of Abercrombie, the modernist responsible for Sheffield’s (1924) radial network of riverside parkways. Just sayin’ 😉

Porter Brook deculverting

Friday found me out and about with ex-colleagues Ed Shaw (ecosystems researcher) and Lewis Gill (Incremental Computing).

First stop-off was at Matilda St, glorious sunshine – great for photos, and a meeting with Environment Agency staff who were involved in the project funding, and notably our feasibility study.

The pocket park (design led by SCC landscape architect Sam Thorn) is looking pretty good. Next steps are to push to open up the connection downstream to the Yorkshire Artspace and BBC Radio Sheffield.

Image copyright Tom Wild

I’ve got some before and after shots, which I’ll get round to uploading sometime…

More to come.