Impacts of Changes in Precipitation in the Province of Córdoba

During the last decade, disasters have been exacerbated by climate change and have affected millions of people on the planet. The United Nations Office for Disaster Risk Reduction (UNISDR, 2015) showed that 91% of the disasters that occurred between 1995-2015 were related to climate (hydrological, meteorological and climatological threats).

Nowadays in the Province of Córdoba (Argentina) are developing climatic phenomena of great intensity that have led to the establishment of national and international projects for study. Numerous localities throughout the province have suffered floods that caused significant damage to the population and its infrastructure. One of the last tragic events originated in 2015 with a flood that affected the towns of Villa Allende, Mendiolaza, Unquillo, Ceballos River, Cerro Azul, Agua de Oro, La Granja, and Salsipuedes and left a balance of six dead , 12 affected bridges (eight partially and four others totally destroyed) and damages from which the population has not yet recovered. The event was rated as the worst natural disaster in more than 20 years.

The current methodology for defining hydraulic and defense structures has stopped working successfully. This methodology uses IDF curves obtained from pluviographic series of 34 years of length (period 1943-1978), and are used to define recurrences up to 200 years. The event registered in 2015 had a recurrence of more than 200 years according to these curves.

The frequent flood events over the Province of Córdoba are significantly impeding their progress towards sustainable development. The changes that are experienced in the intensity of rainfall and its patterns can be caused by changes in temperature that the planet is suffering. This situation has raised the need to improve the understanding of precipitation and flood phenomena, as well as their consequences.

It is necessary, then, to propose guides of good practices to incorporate this new situation in the estimation of the flow for the planning of long-term management, the design and the construction of riparian protections, etc.

In this article the current situation is analyzed and the need arises to establish, among others, new methodologies to be considered in the designs, update of the IDF curves, analysis of series to verify their stationarity against atypical data and their implications and considerations special for determining the background conditions that are established for the modeling.