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The rains recorded over the past few days have helped ease Uruguay’s water crisis, leaving almost half the country’s population without drinking water. According to the official report, the reserves of the Paso Severino Dam, the main source of water supply for Montevideo and the metropolitan area, reached 47% of its total capacity, while in early July they were less than 2%. This has significantly improved the quality of running water after the rise in sodium levels made it virtually undrinkable for 1.7 million people after more than two months.
According to the National Institute of Meteorology, it rained an average of 76 millimeters last week at the Paso Severino reservoir. As a result of the heavy rainfall in recent weeks, the available water in the dam has increased by 10 million cubic meters, which is currently estimated at 32 million. This amount corresponds to almost half of the 67 million cubic meters that can be stored there. In early July, the amount of water did not exceed 1.1 million, or less than 2%, due to the lack of rainfall that the country had for three years, leading to the worst drought in the last 70 years.
Since the end of April, the depletion of the Paso Severino reservoir and the lack of available alternatives have forced the OSE (State Sanitation Works) to limit the use of its main reservoir. The formula used consisted of mixing the fresh water of the Santa Lucía River with other water of the Río de la Plata, more salty due to the oceanic influence. As a result, the allowable sodium content per liter of water doubled dramatically: from 200 to 440 mg. The Ministry of Health urged high-blood pressure and pregnant women, as well as other vulnerable groups, to refrain from consumption. He recommended drinking bottled water, an option chosen by the majority of the population due to the water’s distinctly salty tone.
One of the latest reports presented by the government shows that the sodium level per liter of water is currently at the average level recorded before the crisis, which significantly affected quality. In the three water pumping lines reaching Montevideo and the metropolitan area, sodium averages were 33, 38 and 32 milligrams per liter, well below the 440 mg per liter exceptionally allowed as part of this crisis. The World Health Organization recommends a limit of 200 mg sodium per liter of water.
The Paso Severino Dam is the largest freshwater reservoir, making water drinkable for 57% of the population of Uruguay.Ana Ferreira
Actions of the National Government and the Municipality of Montevidean
After declaring a water emergency on June 19, the Uruguayan government announced the construction of a project to divert water from the southern San José River to the Santa Lucía River to boost reserves that feed Montevideo and the metropolitan area.
Once completed, the transfer began operations on August 10th, adding 200,000 mt3 per day to the area’s water supply, which consumes an average of 500,000 mt3 per day. “This new source of potable water supply for the metropolitan area will be critical as it will allow for more efficient management of the use of the Paso Severino Reservations given the ongoing water deficit,” OSE authorities said. The work, they said, cost $20 million and required 13 km of pipeline to be installed in 35 working days.
In the context of this crisis, the Department of Social Development announced that it would extend economic support to vulnerable populations until September “to ensure the equivalent of buying two liters of bottled water per day per person”. The donation will benefit around 540,000 people in Montevideo and Canelones (in the south of the country). On the other hand, the Montevideo Mayor’s Office ordered the delivery of bottled water to at-risk patients in city polyclinics and the distribution of bottles at more than 220 picnic sites.
Precipitation and the future of drinking water supply
“As much water entered the Paso Severino in one day as in five months,” headlined the local newspaper El Observador, referring to the rains of the past week. OSE sources told this newspaper that the Santa Lucía River, where the dam is located, increased its flow 29-fold in 24 hours. According to the report released yesterday by the National Institute of Meteorology, the cumulative average amount of rainfall in the Santa Lucía river basin during the first 20 days of August was 92.8 mm, “this value corresponds to 100% of the normal value for this period”. Average rainfall in Paso Severino was reported to be 81.6mm.
“Today with Paso Severino, [la planta potabilizadora] Aguas Corrientes and the San José River flyover offer a certain tranquility for a month and a half or two when it hasn’t rained, with good quality drinkable water like the one that comes out of the taps today [grifos] from Montevideo and Canelones,” President Luis Lacalle Pou (National Party center-right) said on August 11 after the completion of the river San José’s river Santa Lucía. “Hopefully there is little left until the water crisis ends,” he added.
In the longer term, the government intends to carry out the Neptuno or Arazatí project, which involves the construction of a water treatment plant in the south of the country. The completion of this work will be privately owned and will use water from the Río de la Plata to supply the city area.
The Neptune Project has received numerous critics from politics and science. Among them is that of a group of scientists from the University of the Republic, who assert that the project “poses a number of environmental problems” and that the salinity of the water of the Río de la Plata “far exceeds acceptable levels”. be made potable.” .