Why is the West salinity drought so harsh this year?

Salinity drought in the dry season 2019-2020 in the Mekong Delta is considered by many to be more severe than the 2016 record year.

The West is experiencing the most severe drought in history. Currently, saline water has affected 10/13 provinces and cities in the Mekong Delta except Dong Thap, An Giang and Can Tho. Five western provinces have declared salinity emergency situations including Ca Mau, Kien Giang, Ben Tre, Tien Giang and Long An.

It is forecasted that salinity this year is likely to be higher than the average of many years and higher than the disaster in 2016. At the same time, the agriculture sector said saline intrusion in the Mekong Delta is very intense and continued. remain high for the remainder of the dry season. Not only that, people in the West also said that it is normal to go through the Lunar New Year to get salt water, but this year's salt season comes very early, some places from November 2019. In 2016, it was considered a record saline wave, once every 100 years, this year's drought broke all previous records.

Saline intrusion in the Mekong Delta is very intense.

Why is this Western drought so terrible this year?

According to experts, the Western drought this year is more severe and even more intense than the history in 2016. Across the current Mekong Delta region, the land is cracking, withered rice, people Carrying each can of water is very common. However, as a rule, every year before a low flood, the next year there will be severe salinity. Due to the low flood in 2019, by 2020, large-scale drought is a warning.

The cause of this drought situation comes from the low rainfall in the whole Mekong basin due to the impact of El Nino phenomenon . This record low rainfall makes the water pour not much downstream . According to the reflection, what people in the Mekong Delta want is heavy rains to reduce salinity and reduce drought in the fields.

It is also because of less rain that leads to dams along the Mekong River basin having to store water until it is fully discharged to generate electricity. This makes the water flow to the source limit is very small and the salinity situation is more serious. Currently, along the Mekong River basin, there are dozens of different hydroelectric dams in China, Laos, Thailand, Cambodia and Vietnam. It is important to know that the construction of hydropower dams not only in the mainstream of the Mekong River but also in the tributaries of the river causes a significant reduction in the water flow of the mainstream.

In addition, according to Nguyen Huu Thien, an expert on Vietnamnet, the drought in the West is also caused by rising sea levels and the system in the Mekong Delta has been disturbed and changed a lot, such as dikes. everywhere water season cannot absorb water into the field. He said: 'In the dry season, there is not much water in the plains, just like a sheet of cloth wiping the board without soaking in the sun and drying it is right. From there, it shows that the delta season does not accept water, but allows it to go directly to the sea. Not to mention the water season, the water has no place to spread to the fields, so it flows into urban areas causing floods'.

It is predicted that by the end of March 2020, saline intrusion in the Mekong Delta will remain high but lower than the middle of the month. According to the Ministry of Agriculture and Rural Development, the forecast of the salinity drought in the dry season 2019 - 2020 will affect the cultivated areas of fruit and people's daily water, with an estimated 80,000 hectares of fruit trees affected.

Under this drought, 80,000 hectares of fruit trees are forecast to be affected.

In April, drought was still serious

According to information from the Southern Institute of Irrigation Science, the volume of Tonle Sap Lake on March 12 was only 1.84 billion cubic meters, so the amount of regulation from the Tonle Sap basin to the downstream is currently negligible. Water resources in the dry season 2019 - 2020 in the Mekong Delta are much lower than the average of the recent 10 years. The average discharge in February 2020 was lower than the average and lower than the 2016 record year.

According to the General Department of Meteorology and Hydrology, the forecast is that from now until April 6, salinity in the Mekong Delta will decrease, the distance from the sea from 35 to 45 km or more at the mouth of the Mekong River is likely. Fresh water appears at low tide, convenient for taking water. However, salinity is still quite high on Ham Always, Cua Tieu and Cua Dai rivers.

However, in April, due to the low volume of water from the upper Mekong to the Mekong Delta, saline intrusion in the region is still serious. This will greatly affect production and daily life, especially in the Mekong River mouth from April 8-15.

By the end of April and early May, the rainy season can start in the South, so the salinity situation in the Mekong Delta area can be greatly improved. However, it is also necessary to take precautions in case of late rain, the flow from upstream to low plain affecting people's lives. According to statistics, currently there are about 95,600 households in the western provinces facing direct difficulties in water sources due to saline drought.

According to the Center for Disaster Policy and Technology, saline intrusion is a phenomenon where salt water with a salt concentration of 0.4% penetrates into the interior of the area during high tide, sea level rise or depletion of water sources. sweet. It is estimated that during the period from March 7 to 15, saltwater intrusion in the Mekong Delta 'peaked', saltwater intrusion reached 100-110 km deep. This means that the saline water during this year's drought has reached more than 100 km inland from the most severe area.

In the period 11 - 13/3 saline intrusion in some rivers as follows: in Vam Co Dong and Vam Co Tay rivers, the range of saline intrusion is 90 - 112km; Cua Tieu and Cua Dai rivers with salinity intrusion range of 55-60 km; Ham Luong river: saline intrusion range of 68 - 80km; Co Chien river with saline intrusion range 55 - 68km; Hau river with salinity intrusion range of 60 - 67km; Cai Lon river, saline intrusion range 55 - 58km.

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