Rice fields in Dong Thap Province's Hong Ngu District are submerged by seasonal floods.
Residents of the delta, which is on the downstream reaches of the Mekong River, have for generations depended on the annual floodwaters to inundate their fields before sowing seeds directly, especially the Plain of Reeds, a wetland straddling Long An and Dong Thap provinces.
Usually, the flooding would start late July or early August and remain until November or even later, blessing the region with extraordinary fertility as they deposit silt from upstream areas.
This year, the seasonal flooding had not happened until September; and in recent years, the delta has been deprived of its annual blessing by upstream dams and climate change impacts that have altered and weakened the regular regime.
Nguyen Van Doan and his wife sort the fish, crabs and shrimps they've caught in Dong Thap's Thap Muoi District, Nov. 13.
"The floodwaters have never been this low," Doan said, adding that he has not been able to catch much fish so far in this season.
According to the Dong Thap hydro-meteorological station, the flooding level in the province was 0.1-0.2 meters lower than last year and 0.4-1.3 meters lower than in previous years.
Nguyen Thi Khen, 48, sits in a hut by a branch of the Tien River, a tributary of the Mekong River, in Dong Thap's Hong Ngu District. The river, which originates in Tibet, flows through China, known as the upper basin, and lower basin countries of Myanmar, Laos, Thailand, and Cambodia, before spreading across Vietnam's Mekong Delta and reaching the sea.
For the past four years, Khen and her husband have had to move to the hut, which lies 20 km away from their home, every time the flooding season comes.
In the past, they did not have to go anywhere far from their neighborhood in Thuong Thoi Thien Commune to catch fish because the supply was plentiful, but things have changed dramatically in recent years.
The annual flooding that has nourished the delta for millennia has arrived late, been deficient or even absent in recent years. Experts have blamed it on climate change and the construction of a series of upstream dams.
Two men, Thai (L), and Thang wade into the floodwaters to catch moina in Hong Ngu District. Moina is a crustacean species that is normally used to feed fingerlings. The annual flooding season is also peak moina season.
The men sell the moina to fish farmers at VND4,000 per kilo. On a good day, they can earn VND200,000-300,000 ($8.83-13).
A family goes on a flooded rice field in Dong Thap's Hong Ngu District. The man rows the boat and the woman picks fish from the net. The kid has a fun time.
Floodwaters are a treat for the water chestnut, a grass-like sedge that is a delta specialty. People use the plant’s fruit and its top part for food and other parts as fertilizer.
Nguyen Van Den in Phu Hiep Commune, Tam Nong District, Dong Thap Province, harvests the sedge for sale. He can earn VND200,000 after a day of hard work.
A woman in Tan Lap Commune, Moc Hoa District, Long An Province, Dong Thap’s neighbor, untangles her fishing net.
She said that this year, local fishermen could only catch 2-3 kilos of fish for every 1,000 meters of net cast, on average, which is just one-fourth the catch of previous years.
Tran Van Thanh, 63, catches crabs in Long An, something he has been doing for 10 years.
He said he could get 10 kilos of crabs per day in the past but now, three-four kilos per day is the best he can manage.
Tong Van Thi, 49, holds a trap with frogs in it in Tan Lap Commune. In this wet season, he sets up 40 traps in the evening and returns early in the morning to collect the traps. On average he has been catching 2-3 kilos of frog per night. He sells them for VND50,000-65,000 per kilo.
Floodwaters have started withdrawing from rice fields in Dong Thap Province, marking time for the winter-spring crop.
The floodwaters, especially overland water, provides migration routes and breeding sites for many species of fish, distributes sediment that retained nutrients for agriculture, recharges groundwater aquifers, and prevents salt intrusion, not to mention washing away all the chemical residues left from previous crops.
When the annual flooding does not happen or happens late, as has been the trend in recent years, cropping and fishing activities are disrupted.
