Parched fields under drought as farmers hope for a salinity-control dam

Prolonged heatwaves and worsening saltwater intrusion are placing increasing pressure on agricultural production in the lower Vinh Dien River basin. Thousands of hectares of rice and other crops in Dien Ban Dong Ward, Dien Ban Bac Ward, and Go Noi Ward in Da Nang City are facing the risk of lower yields as irrigation water becomes increasingly scarce. While short-term response measures are being implemented, local farmers continue to hope for the construction of a permanent salinity-control dam to secure long-term agricultural production.

Fields left parched during the peak of the dry season

Under the scorching summer sun, Le Thi Muoi stood quietly beside her rice field in Dien Ban Dong Ward, watching the crop, now entering the panicle initiation stage, begin to turn yellow from a lack of irrigation water.

Just a few days ago, Mrs. Muoi said her family was still hoping for another release of fresh water from the Vinh Dien River to save their rice crop. However, prolonged extreme heat has caused water levels in the irrigation canal system to steadily decline, while the river itself has become increasingly affected by saltwater intrusion.

Rice is the family's primary source of both food and income. After months of investing in seeds, fertilizers, labor, and pest control, the crop has reached its most critical stage for determining yield, only to be threatened by severe water shortages.

During the hottest days, farmers head to their fields at daybreak to monitor water levels in the irrigation canals and wait for updates on pumping station operations. However, when river salinity rises beyond acceptable levels, many pumping stations are forced to reduce capacity or suspend operations altogether to prevent saltwater from entering the rice fields.

Rice is not the only crop affected. Vegetable fields along the riverbanks are also facing severe water shortages. Some households have resorted to using groundwater from wells for limited irrigation, but groundwater levels have dropped rapidly during the dry season, causing many vegetable crops to grow poorly or wither.

For residents living along the lower reaches of the Vinh Dien River, drought and saltwater intrusion are no longer unusual events. What concerns them most is that these conditions have recurred year after year. Each growing season, farmers must wait for fresh water from upstream, for salinity levels to decline, or for pumping stations to resume operation. Meanwhile, rice plants continue to grow according to nature's timetable and cannot afford to wait.

Residents hope for a permanent saltwater barrier

The Vinh Dien River currently supplies irrigation water to more than 2,000 hectares (about 4,940 acres) of farmland through 14 pumping stations. It is also a vital source of water for domestic use and a wide range of economic activities in the downstream area. When saltwater intrusion intensifies, the entire agricultural region that depends on the river's water supply is affected.

To mitigate the impacts of the peak dry season, Da Nang City has invested in constructing a temporary saltwater barrier across the Vinh Dien River in Dien Ban Dong Ward. The structure, approximately 105 meters (344 feet) long, was built at a cost of about VND 2.6 billion and is designed to retain fresh water for agricultural production.

However, local agricultural authorities said the measure is only a temporary fix. Each year, the locality spends about VND 3 billion to VND 4 billion on building the saltwater barrier, only to dismantle it during the rainy and flood seasons to maintain drainage capacity. Over the past decade, repeatedly building and removing the structure has cost the state budget more than VND 30 billion.

Alongside this short-term response, Da Nang has instructed the agricultural sector to complete a proposal for a permanent saltwater barrier on the Vinh Dien River. Many farmers say only a durable structure capable of actively regulating water flows can provide long-term protection for thousands of hectares of rice and other crops, as well as local livelihoods.

Residents have expressed hope after learning that the city is preparing the proposal for submission to the relevant authorities for investment approval. Tran Van Tu, a farmer in the Tu Cau area, said local people want the project to be implemented soon, with a properly designed gate system that can retain fresh water during the dry season while still allowing floodwaters to drain during the rainy season.

As climate change intensifies droughts and saltwater intrusion, a permanent saltwater barrier has become more than just a long-held aspiration of local residents. It is increasingly seen as an urgent investment needed to safeguard one of Da Nang's key agricultural production areas, secure freshwater supplies, and protect rural livelihoods over the long term.

$1 = VND 26,450 - Source: Vietcombank.