OCAPI Program (english)

Studying and supporting the evolution of urban nutrition/excretion systems

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

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Our goals :

OCAPI 2 : 2018 – 2021

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

OCAPI 1 :  2014 – 2018

  • Characterize socio-ecological regimes of occidental cities, by focusing on  nutrition/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, being 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.

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# Martin, T. M., Esculier, F., Levavasseur, F., & Houot, S. 2020. Human urine-based fertilizers: A review. Critical Reviews in Environmental Science and Technology, 1-47.

# Pruvost-Bouvattier, M., Vialleix, M., Jovéniaux, A., Esculier, F., 2020. Recovering nitrogen and phophorus from urine to improve ecological and food security Note rapide de l’institut Paris région n°858.

# Legrand, M. & Meulemans, G. 2020. Bathing in black water? The microbiopolitics of the river Seine’s ecological reclamation. In Sariola, S., Rest M. & Brives C. (ed.) With the microbes. [in press].

# Legrand, M., Jovéniaux, A., Arbarotti, A., de Gouvello, B., Esculier, F., Tabuchi, J.P. 2020. The emergence of systems for the source separation and valorization of human waste in Greater Paris: from necessity to implementation.  Water and Megacities Conference – UNESCO (évènement reporté à 2021).

# Aubert, A. H., Esculier, F., & Lienert, J. 2020. Recommendations for online elicitation of swing weights from citizens in environmental decision-making. Operations Research Perspectives, 7, 100156.

# Esculier, F., Barles, S, .2019. Past and future trajectories of human excreta management systems –the case of Paris XIXth-XXIst centuries. In: The Seine River Basin. Flipo, N., Labadie, P., Lestel, L. (Eds). The Handbook of Environmental Chemistry. Springer, Berlin, Heidelberg.

# 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 573 : 1028-1045.

# 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.

# 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.