Construction of the system worth VND3.3 trillion ($142.17 million) started in November 2019, with two parts on the Cai Lon and Cai Be rivers, both originating in Hau Giang and passing through Kien Giang before meeting the sea.

The part on Cai Be River will enter operation in mid-February. It spans 85 meters wide with two compartments.

Work on an irrigation project on the Cai Be River, southern Vietnam.
Photo by VnExpress/Linh Hoang.

The entire irrigation system, invested by funds raised through government bonds, is expected to irrigate 384,000 hectares of land, of which 350,000 hectares are for agriculture and aquaculture, in Kien Giang, Hau Giang, Ca Mau and Bac Lieu provinces of the delta.

The part on Cai Lon River is bigger, stretching 455 meters in width and boasting 11 compartments. It is scheduled to be completed in June, four months prior to schedule.

Both parts have locks of 15 meters in width each, aside from sewers, valves and hydraulic cylinders that make it the largest irrigation system ever in the region, which has for decades functioned as the nation’s agriculture and aquaculture hub.

The system further includes bridges and embankments that connect with national highways.

It would combine with a coastal dam in the region to combat climate change, rising sea levels and flooding, as well as help develop infrastructure for road transport.

Part of an irrigation project on the Cai Lon River, southern Vietnam.
Photo by VnExpress/Linh Hoang.

According to the Irrigation Work Investment and Construction Management Board No.10 under the Ministry of Agriculture and Rural Development, which oversees the project, it normally takes 40-48 months to complete an irrigation system of such scale but due to the urgency of protecting the region from drought and salinity, which has grown worse in recent years, progress has been sped up to just 20-24 months.

During the last dry season, which normally lasts from November to April in southern Vietnam, saline levels of up to six grams per liter were found in some areas. Salinity of one to four grams was found 50 kilometers (31 miles) upstream on average, and up to 130 kilometers, in all tributaries of The Mekong. Salinity above one gram is considered unpalatable and levels of above two are unsafe for most crops.

The provinces of Ben Tre, Tien Giang, Long An, Kien Giang, Ca Mau and Soc Trang to declare an emergency after drought and saltwater damaged around 43,000 hectares (166 acres) of paddy and caused 80,000 families to suffer water shortage.

The government has since given them and two other provinces VND530 billion ($22.77 million) to deal with drought and salinity.