OCAPI Program

Studying and supporting the evolution of urban alimentation/excretion systems

OCAPI research & action program was launched in 2014 in France. It aims at studying the contemporary mutations of urban nutrient flows, and more specifically, the management of urban nutrient excretion.

One century after the generalization of sewer systems, OCAPI is one of the first French academic research programs that opens the debate about management options for human urine and feces in the city. It proposes to explore the potential of urine diversion, and more generally, new alternative decentralized approaches of urine and feces sanitation.

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Our goals :

OCAPI 1 :  2014 – 2018

  • Characterize socio-ecological regimes of occidental cities, by focusing on  alimentation/excretion systems & their sustainability.
  • Analyse socio-ecological trajectories of French cities since the industrial revolution until recent generalisation of the quasi monopolistic trio « flush toilet,  sewer, water treatment plant ».
  • Provide feedback on different sanitation concepts, that are theorized, beign developed or already built abroad (Netherlands, Sweden, Germany, etc.) and compare their energy and material flows.
  • Identify hindering and driving forces of implementation of new sanitation techniques in France and support the development of pilot projects in the Greater Paris Area.

OCAPI 2 : 2018 – 2021

  • Adapt urine diversion strategies to different urban typologies.
  • Developand compare the agronomic and environmental performances of different value chains for by-products obtained by urine diversion.
  • Understand contemporary practices, knowledge & imaginaries about excretion and urine valorization.
  • Support of urine diversion stakeholders at a regional, national and international level.

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# Esculier, F., Le Noë, J., Barles, S., Billen, G., Créno, B., Garnier, J., Lesavre, J., Petit L. et Tabuchi, J.-P. 2018 “The biogeochemical imprint of human metabolism in Paris Megacity: a regionalized analysis of a water-agro-food system”. Journal of Hydrology. In press.

# Le Noë J., Billen G., Esculier F., Garnier J. 2018 Long term socio-ecological trajectories of agro-food systems revealed by N and P flows: the case of French regions from 1852 to 2014. Agriculture, Ecosystems & Environment. 265, 132-143. https://doi.org/10.1016/j.agee.2018.06.006

# Verger, Y., Petit, C., Barles, S., Billen, G., Garnier, J., Esculier, F., Maugis, P. 2018. A N, P, C, and water flows metabolism study in a peri-urban territory in France: The case-study of the Saclay plateau. Resources, Conservation & Recycling, 137 (2018) 200-213. https://doi.org/10.1016/j.resconrec.2018.06.007