Friday , August 19 2022

Availability has dropped to 37% in some areas


On April 21, 2018, Cape Town, in South Africa, was about to run out of a water leak, a point whose residents and authorities have called "Zero Day". Although the situation is being reversed, this almost collapse of water portrays the vulnerability of water availability, a phenomenon that is replicated across the planet, including Chile. The problem is to be in our country, the National Water Balance, dating up to how much water is available 1987

So, right now General Water Directorate (DGA) working in the National Water Balance Update Project To update this registry, the work trusted to a consortium that includes the Catholic University and the University of Chile, as well as the Center for Advanced Technology for Mining (AMTC) and the project Climate and Resilience Project (CR) 2 what consider completing four reports.

The first, which included the methodology to update the stand, was introduced in 2017. During 2019 the other three will finish, which will measure the water balance has been distributed in three macro domains.

The second report is responsible for the macro zone in the north and center; the third develops the information of the southern zone and the northern part of the southern zone; and the fourth works information of the missing part of the current domain, completing a recent balance of 101 basins that exist in the country in this way.

To compare the values ​​for water availability, and to prove that the methodology is consistent, it has been considered five pilot basins representative of the national territory ", they explain the DGA.

The river basins selected were the rivers Loa, Choapa, Maipo, Imperial and Aysén. "The information from the details of each of the basins, in the reports that will be submitted during 2019, "adds the organism.

However, the first measurements showed a lack of water availability in the areas studied between 10 and 37%.

The project is led by Ximena Vargas, Academic Faculty of Physical and Mathematical Sciences of the University of Chile. "What was found at arrival stations and measurement temperature is that, in general, there is reduction in average annual deposition and increase in average annual temperature ". This, explained, has created a reduction in water available at some stations of coastal sectors. "Comparison of the available values ​​for water availability (which dates from 1987), receives annual rates around the water (rainwater flowing freely through land ) 10% to 37%"He's saying.

Panel of experts, detailing the report.

According to Vargas, as well as the first report, published in 2017, this second document, which covers the basins of the north and center's basins in the process to fill in. "The third project is currently being done: Application in macron basins to the south and most northeast of the east and here two introductory reports were presented. "The reported variation corresponds to what has been done so far in basins of northern, central, south and south macers," he said.

Roberto Rondanelli, a civil engineer from the University of Chile and a specialist in meteorology, has been part of the research since its inception in 2017. "In 1987 there was little awareness that hydrology was a big change. For the remains we have seen a fall in the mid-country and country (between Valparaíso and Aysén). In fact, rainfall increases as a 50 ° S latitude. We live quite dry period, has triggered naturally. However, there are anthropogenic factors that are associated with climate change. This reduction is semi-permanent, and can not be reversed in the medium or long term. Unless C02 levels in the atmosphere are reduced, "it warns.

This work earns value, as it is also essential to know that the availability of basins and the country, to implement public policies and the design of new projects, is in the middle of the debate by the Water Code and the effects of climate change worldwide.

A view of Monte Patria and its surroundings, which is affected by severe drought. Photo: The Third / Archive

According to the DGA, "The extent of the deficit at a national level will be known once the fourth final report has been published. ", since the balance of macro domains has to build at the moment. So, once the macro-zone zone has been completed, the updated water balance report will be combined. It's important to emphasize that the comparison is only restrictive, due to the methodological differences, "says the DGA.

"Despite the above, a in the basins or those sectors where the lack of water is apparent, the General Water Directorate, works with short and medium term measures, establishing restricted areas and / or exclusion zones for the constitution of new underground rights; buy a ruling to those areas that are in extreme drought situation; command of operation of extraction control systems; promoting the organization and operation of water user organizations; oversight of irregular extraction; and, studying the decision for a temporary reduction in abstraction, "stated the DGA.

Modeling Methodology

In the study, "they are being used complex modeling methodologies and supercacy capacity they were not available 30 years ago to estimate, in the first place, the climatic variables, rainfall and temperature predominantly, to triple timescale, during the entire period from 1985 to 2015, in cells of about 5km by 5km for the whole national territory, "Vargas explained.

Then, and evapotranspiration and rhediad in each cell from the basins fund, the northern, center, southern and northern continental macrones, which are considered in a natural system or with small interference, add Vargas.

At present, this process is carried out in basins and southern macros and extreme to the north of the surrounding area, "says Vargas.

Published results contribute to the final analysis of the current 101 waterways in the country. "The first report produced information that could be used for studying and building strategic water resource management plans in waters. These strategic plans for the 101 circuits of Chile follow a different objective than the water balance, namely the integrated management of resources water ", indicates the DGA.

Roberto Pizarro, a forestry engineer at the University of Chile and a hydrologist, from the Polytechnic University of Madrid, indicated that the balance of the basins would be expected to give values ​​as published. "There are very specific details, we are a country where it is Our GDP is based on natural wealth. Mining, forestry, agriculture, all of these activities need water. If you add tourism, even more. Importance is that water represents at least 60% of the GDP of Chile. For an idea, mining is about 12%. It's an extremely valuable resource. "

Rondanelli establishes that seasonal change of flow, more water in the winter and more summer drought. "The snow areas have been reduced in recent years, caused by the increase in global temperature. That causes the balance of water that dissolves against a drop becomes destabilized. It drops in the snow area in the mountains by increasing the temperature in height. Seasonal change in agricultural areas causes a change that may be anxious. This effect is remarkable to Chile and the Andean countries. "

The economic growth of the country goes hand in hand with water use. "From year 90 to date our GDP has increased around three times, and the use of water has grown in the same proportion. We eat it three times higher and, therefore, we have combined economic growth to water consumption. If we want to continue to grow at that level, will we be able to get all the necessary water if we are already in trouble? I do not lose the figure of University of Chile, because there has been an increase in the adverse use. At present, we are in a position of climatic uncertainty, this refers to variation and climate change, "added Pizarro.

Pizarro notes that the problem of eating, uncertainty and variation of climate change and territorial problem. "We are a big issue of citizen awareness about the matter. We do not have any information about what is really the case in our ecosystem. We are not clear that the passing waters today, or their origin or temporary origin. One of serious problems is that the disposal of the actors or such resources, which is damaged by any other, amendment. "

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