Interview with Ian Vázquez-Rowe and Ramzy Kahhat.
Associate professors of the Pontifical Catholic University of Peru.
As a result of the adverse climatic episode suffered by the Peruvian coast at the beginning of 2017, much has been said about the need for a strategic, formal and structured reconstruction in order to minimize the vulnerability of the population in the face of climate change and increase the resilience of our urban areas. However, it should be noted that for this desire to be a reality in the medium term, it is necessary to open channels of scientific and technical reflection in order to understand the consequences that this type of natural disasters have in complex societies. This will allow to generate recommendations of greater depth so that they can be used in public policies.
At the end of June 2017, PUCP professors Ramzy Kahhat and Ian Vázquez Rowe published an opinion piece in the international scientific journal Science of the Total Environment, focusing on the events that occurred in Lima during the crisis, which left the city without water for almost a week. Regardless of the emergency situations that were experienced in some districts of the city, causing panic among the residents and numerous evacuations in areas of informal urbanism, the high turbidity of the Rimac River prevented the collection of water for its purification in the treatment plant of water of “La Atarjea”, main supply of drinking water for the metropolis.
The publication, entitled “Natural disasters and climate change call for the urgent decentralization of urban water systems”, starts from this specific situation with the objective of reflecting on the need to carry out a deep revision of the urban water cycle in the city of Lima, and by extension, to other cities in Peru, Latin America, and any other city in the world that is exposed to high vulnerability to natural disasters. In the case of Lima, for example, the preponderant dependence of the La Atarjea plant when it comes to obtaining potable water, not only implies that it depends totally on the Rímac River, with its seasonal flow variations, and its vulnerability to droughts and progressive Andean deglaciation, but also generates significant risks from a seismic perspective and thus compromising the resilience of the city’s water system.
Lima has a centralized system of distribution of drinking water, which implies a greater probability than, for example, before a seismic event of great magnitude, the city runs out of water temporarily for days or weeks. In this sense, the article advocates the progressive transition towards a decentralized water system, in which other sources of water are used to supply the city with drinking water, such as the reuse of wastewater that has been treated with sophisticated technologies or the desalination of water from properly designed projects. This would allow the early warning systems of the city to prepare drinking water distribution points more quickly and efficiently, since in the face of a natural disaster, such as a large earthquake, the water distribution network is also It could be badly damaged. Finally, it is important to emphasize that the national reconstruction plan must embrace urban resilience criteria that minimize the impacts to society caused by natural disasters.
Quote of the publication:
Vázquez-Rowe, I., Kahhat, R., & Lorenzo-Toja, Y. (2017). Natural disasters and climate change call for the urgent decentralization of urban water systems. Science of The Total Environment, 605, 246-250.
