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Tom Hart

MA work

Immune System for the City

Society's relationship to effluence is a tricky one, loaded with centuries of scientific and medical advancement, effluence has always stood at the epicentre of, though often at the background of, any discussion of what it is to be dignified and civilised. The modern human is clean, sanitised, and has access to a modern sewage systems accessed via the sealed portal that is the flushing toilet, and by this token is dignified. The modernist movement has stood for over a century to reinforce this ideal, though today it seems we are more equipped than ever to begin challenging this.

Presently effluence manifests as part of a linear cycle of production, consumption and disposal, a practice alienating us from our most base matter in a mechanism referred to by Marx and others as Metabolic Rift. Recent scientific advancements allow us to approach and handle dirt, and in particular the “worst” kind, shit, in different ways we can begin to see and contemplate new identities to shit, allowing us to challenge and rectify our estrangement from it. There is no moment where this estrangement becomes more apparent than when sitting on the toilet. Sitting as you may within the most sanitary and hyper-cleansed space within any given building, it is clear this hyper-sanitisation is at odds with both our internal world and the one beneath our feet. The sewage network is, you could say, a cornerstone of the sanitary revolution and ergo civilised society, a movement that continues into the present day demonstrated by the preoccupation of many with hand sanitizers and endless bacterial sprays for the home; 99.9% clean is good and not to be challenged.

This obsessive appetite for cleanliness has, however, in recent years been attributed to growing cases of inflammatory and allergic diseases, from asthma and eczema, through to crohn's disease, autism and cancer, in the hygiene and old friends hypotheses. These suggest an estrangement from the specific kinds of dirt our immune systems evolved surrounded by and became dependant on leads to overactive immune systems that target harmless microorganisms and cells, such as pollen in the case of hay-fever sufferers, in lieu of these “old friends”. Therefore how can we combat this growing pandemic amongst our modern urban populations whilst attempting to address metabolic rift?

Immune System for the City attempts this with four tactics, Immune Corridors, Micro-Sewage Treatment Works (MSTWs), Public WCs and Transparent Manhole Covers. Much like Haussman’s Grandes Boulevards linked the cities new and existing Green Lungs in Paris, the proposed Immune Corridors follow the routes of London’s extant and extinct rivers connecting many of the city's principal green spaces, such as Green Park where this strategy is tested. Within the existing parks connected by the new Immune Corridors, MSTWs manage effluence locally, directing its fecundity directly to the local environment, strengthening biodiversity and and translating into numerous site specific programs such as spas, breweries and wild parkland that provide an opportunity to mix with effluence and re-evaluate the city's relationship with it. Thirdly new public toilets allow visitors to these parks to directly contribute to this source, while answering a growing lack of public WCs throughout the city. Lastly transparent manhole covers simply and literally expose this hidden world and its workings at points of intersection with existing infrastructure.

With these tactics effluence is brought back into the city in a gesture that transforms the urban condition into both an ancient and new one. This is done not by a simply grafted pedagogical sign of what used to exist, but a subtle transformation of the landscape into one that within which the human immune system can thrive, and the condition of the modern human can evolve.


  • MA Degree


    School of Architecture


    MA Architecture, 2016



  • Degrees

  • BA (Hons) Cantab Architecture, University of Cambridge, 2011
  • Experience

  • Design assistant, Bjarke Ingels Group, Copenhagen, 2013–14; Architecture internship, Sauerbruch Hutton, Berlin, 2012–13; Architecture internship, MVRDV, Rotterdam, 2012–13
  • Exhibitions

  • ArcSoc 2012, Farmiloe Building , London, 2012; Vertical Village IBA w/ MVRDV, Hamburg Museum, 2013