Why do we flood?

Why do we flood?

By Eduardo Aguirre Madariaga

The answers vary from irony to the development of endless mathematical equations, depending on the person consulted. The idea of ​​this summary is that apart from knowing the reasons, we become aware of the real situation that we have to live and how we could live better with this phenomenon.

We know that Resistencia, Barranqueras and Vilelas are located in the flood valley of the Paraná River. If we look at fig. 1 we will see that all our activities are carried out within the river (and we do not have scales), there we are and there we intend to continue being with increasing investments, and of course with greater risks.

Through the construction of the defenses, the risk character has been modified, we have some security with the river, but in return a new form of flood has arisen by altering the natural runoff of the waters. This is intended to be offset by pump stations.

All this shows a wrong location for the urban agglomeration of the Great Resistance, which should naturally grow towards higher and more suitable lands, as logic indicates, towards the northwest; but reality indicates, against all logic, that it is intended to continue advancing on the alluvial plain of the Río Negro.

In a coherent attempt to limit the indiscriminate advance of urbanization, the Provincial Water Administration has issued Res. 1111/98, which is a series of zoning for land use due to the danger of flooding, which in synthesis deals with directing the urbanization towards the places protected by its height, not allowing the same towards areas that are naturally flooded, in short it defends the property of individuals, and of the entire city the latter is not always interpreted in this way.

Today the inhabitants of Resistencia live with rains that do not exceed 50mm and despite the low millimeter, it hinders the normal functioning of the city. The magnitude of these inconveniences have increased over the years, being affected areas that years ago were not, today this process has grown involving almost the entire city, causing inconvenience due to lost time, economic losses and social disorders. As I mentioned previously, as the natural runoff is altered with the defense works, the only possibility of not being flooded by rains are the lagoons associated with the pumping stations.

This issue deserves a special awareness on the part of society as a whole, there is a tendency to make them disappear by filling them in, to gain space to continue urbanizing, we pay dearly for this error, in image 2 the existence of four gaps that Today they no longer exist, this is just an example, and any citizen knows of the inconveniences that occur with rains in the area of ​​Av. Hernandarias and Salta, Entre Ríos and Corrientes, Irigoyen and Av. Italia, Don Bosco and Monteagudo , D. Bosco and Italy etc. We will talk about drains associated with waterproofing on another occasion.

If they were filled, the water does not have to accumulate in that area, could it be that the water has a memory? The answer is very simple, only the water surface has been covered, the supply basin is still intact, as shown in graph 1.

In 1999, Eng. Parini and Clemente, within the framework of a postgraduate degree in urban hydrology, carried out at UNNE, presented a work on the Impact of Urbanizations in areas occupied by the Río Negro. In this study, two scenarios are analyzed, the first in which the Colussi lagoon is filled for subdivision and urbanization, and in the second, the lagoon is maintained as a reservoir and is used as a recreation and leisure area. The conclusions are detailed in the following table:

For the first hypothesis

Cost of works: fillings, mov. of soil, pipes and pumps $ 1,730,000
Maintenance cost: (monthly) $ 8,602
Benefits: (monthly) tax. real estate, Sanitation rate for 2 years $ 15,633

For the second
Basic infrastructure required $ 30,000
Maintenance cost (monthly) $ 2,625
Among the conclusions we can cite:

for alternative 1

The need to divert the volume of water, which was previously stored in the Colussi lagoon, to another basin, in this case the Teros, the inhabitants of that sector see an increased risk of flooding, by increasing the pumping capacity, it forces them to depend permanently of maintenance and control operators, compromised situations have been experienced in which some of these aspects have failed for various reasons, endangering the population and its assets. Citizens who want to live in this area cannot be benefited, involving and putting at risk a large area of ​​the city, since the contribution area extends to Laprida Street, the new occupants will also suffer if the system fails. Therefore, the number of people living at risk is increasing.

For alternative 2

The population of the entire basin is benefited by maintaining the natural environments and without increasing the risk in the neighboring basins.
By enabling properly prepared green spaces, the natural runoff system is not destroyed and the lagoon continues to act as a regulatory reservoir of excesses.
Personally I think that the way forward to improve our quality of life is clear, reversing is impossible, now we must take care of what we have left. We must not forget that Resistencia is a water-dependent city, and that just as the defenses protect us from Paraná, the lagoons are our internal defenses for rainy days, and that each cubic meter of land that is thrown into them means a cubic meter of water in another sector of the city, which can be you, my or our houses.

* Eduardo Aguirre Madariaga Surveyor [email protected]

Video: The causes of flooding (June 2021).