Mekong Delta actively respond to drought and saltwater intrusion in the dry season 2021-2022

Saltwater intrusion coming early

The ENSO phenomenon in the La Nina state will continue to maintain a weak intensity. During the first months of 2022, sea surface temperature tends to increase gradually but is still lower than the average temperature of previous years and the ENSO is still in a weak La Nina state. 

From about April to May 2022, ENSO is likely to gradually transition to a neutral state.

Regarding rainfall forecast, from January to March 2022, the total rainfall tends to be higher than the average of the same period of previous years due to the possibility of unseasonal rains. By April, the total rainfall is 10 to 30 per cent higher than the average. By May, the total rainfall is approximately the same as the average rainfall of the same periods of previous years.

In the first half of 2022, three high tides are expected in the coastal areas of the southern provinces from January 28 to February 3, from February 26 to March 5, and from March 28 to April 3. Thus, it is necessary to pay attention to the occurrence of unseasonal rain in the dry season of 2021 - 2022.

It is forecasted that saline intrusion in the dry season 2021-2022 in the Mekong Delta will come earlier with a deeper impact than the average water level in recent years. However, the level of saltwater intrusion will not be as severe as in 2019-2020.

4,000ha of crops in Bac Lieu lacks fresh water

In Bac Lieu, risks of severe drought and saltwater intrusion are expected during the dry season 2021-2022.

Specifically, for the 2022 winter-spring rice crop, there is a risk of water shortage because the additional source of freshwater from the Hau River to Bac Lieu via the Phung Hiep route is expected to be short. High temperatures will increase the early evaporation and saltwater intrusion will make it difficult to get water from Soc Trang to Bac Lieu.

The quality of freshwater is forecasted to be more likely to be contaminated with alum.

The production cost of the winter-spring crop will increase if the water supply for production and weather conditions are unfavorable.

Due to the impacts of prolonged drought and saltwater intrusion, vegetable production will face difficulties,

It is forecasted that the vegetable area is at risk of freshwater shortage in March and April 2022. Moreover, the quality of freshwater is not high due to alum contamination, leading to low vegetable yield.

There is a high possibility that 4,000ha of rice area on shrimp land of Gia Rai town, Phuoc Long district, and Hong Dan district of Bac Lieu province are at risk of freshwater shortage and yield reduction in January 2022.

It will be also difficult to find freshwater to supplement salinity in aquaculture growing ponds.

Coping to difficulties, the People's Committee of Bac Lieu province actively promulgated a scenario to prevent and control drought and saltwater intrusion in the dry season in 2021-2022.

Accordingly, the province mapped out three scenarios that this year's dry season will be less severe, the same, and more severe than the "historic" dry season of 2019 - 2020. Bac Lieu province requires relevant agencies to prepare for the situation in which this year's dry season is as severe as the 2019 - 2020 dry season.

In addition, the province has spent more than VND18.6 billion to build 89 dams for the rice-shrimp crop, 448 dams for the winter-spring crop, to support water pumping, additional drilling and extension of clean water pipes.

Soc Trang recommended the production of salt-tolerant rice varieties 

To proactively respond to the drought and saltwater intrusion, the People's Committee of Soc Trang province has directed the provincial Department of Agriculture and Rural Development to request the management units to exploit the irrigation works, to develop specific water regulating schedules and reasonable sluices operation to prevent salinity to ensure water supply for agricultural production and aquaculture.

At the same time, farmers are urged to do intra-field irrigation to sow following the schedule recommended by the functional sector.

Hong Minh Nhat, Head of Economic Division, Nga Nam town (Soc Trang) said that the town actively coordinated closely with neighboring districts such as My Tu district (Soc Trang), Long My town (Hau Giang) and Hong Dan district (Bac Lieu) to reasonably prevent saltwater from entering the local freshwater area.

“The irrigation management station of Nga Nam town actively cooperates with the irrigation station of Hong Dan district and the Ninh Quoi boat lock management board to know about saltwater intrusion and to notify the people in time so that they could pump to reserve water," said Nhat.

Nhat said that the saltwater will enter Nga Nam town in two ways. One way is along the river, Phung Hiep road, through Ninh Quoi lock when opening and closing the sluice for vehicles. The other way is through Xeo Chich river at Ngan Dua ferry, Hong Dan district.

The Economic Department of Nga Nam town has proactively advised farmers to produce in a safe direction, choosing rice varieties that are resistant to salinity reaching a threshold of 1-2 per cent.

The town regularly directs localities to dredge irrigation canal systems, in-field irrigation and strengthen closed dikes. The whole town is running 66 pumping stations and 36 pump boats to actively pump and store water.