Vietnamese weather forecasters expect the 2026 rainy season to end early, between late October and early November, with rainfall potentially more than 50 per cent below the long-term average and surface water supplies falling by 50-70 per cent.
Saltwater with a concentration of four grams per litre could penetrate 40-60 kilometres inland from late November.
Nguyen Tran Thuc, head of Ca Mau's Crop Production and Plant Protection Sub-department, said about 95,316 hectares of farmland could be affected by drought and saltwater intrusion, particularly rice-shrimp and winter-spring rice areas.
Southern Ca Mau is considered particularly vulnerable because rice farming there relies almost entirely on rainfall, with no supplementary freshwater supply.
Weather and water conditions are being closely monitored, with planting schedules adjusted as needed. Farmers are advised to use short-duration, salt-tolerant rice varieties and rainfall to flush salt from fields.
Ca Mau has more than 80,000 hectares of rice-shrimp farmland, one of Vietnam's major production areas. Agriculture officials have called for detailed response plans identifying areas at greatest risk.
Water shortages are also a major concern. Around 13,770 households could face shortages, particularly in coastal and remote areas and places where surface water is affected by salinity or acidity.
The province plans to repair and upgrade its water supply infrastructure, including 46 deteriorating facilities and 92 that are no longer operating. Urgent rural water projects planned for 2026-2028 are expected to serve around 7,000 households.
For communities that cannot yet be connected to water pipelines, authorities plan to provide storage tanks and arrange temporary water deliveries during the peak dry season.
Ca Mau aims to identify all households at risk of water shortages by September 30 and put water supply plans in place before the dry season.
The province also plans to complete its autumn-winter rice planting by Octocber 15, while areas without secure water supplies will not be planted.
From late October to early November, authorities plan to close sluice gates where necessary to retain freshwater and prevent saltwater intrusion. Monitoring and warnings for drought and salinity will be stepped up from mid-November.
Aquaculture farmers have also been advised to adjust stocking schedules and densities to water conditions and avoid expanding production or starting new crops unless adequate water supplies can be secured.
Ca Mau authorities said the measures were aimed at reducing losses from drought and saltwater intrusion during the 2026-2027 dry season while strengthening the province's longer-term resilience to climate change.