Iftekhar Ahmed Fagun

Managing haor conditions requires an integrated approach that considers crop production and aquatic health; early warning systems based on upstream rainfall data must be strengthened, writes Iftekhar Ahmed Fagun

OVER the past week, heavy to very heavy rainfall in the upstream hills of Cherrapunji and Meghalaya, combined with ongoing rainfall within Bangladesh, has pushed large volumes of hill  water into the haor basins of Sylhet and surrounding districts. Although a full-scale flood has not yet formally occurred, this early influx of water arriving before the completion of the boro harvest has already created widespread waterlogging and uncertainty. Importantly, this situation did not arise without warning. Both the India Meteorological Department and the Bangladesh Meteorological Department had forecast heavy rainfall and the likelihood of early flash flood conditions in the region.

As floodwaters continue to move from the hills of Cherrapunji and Meghalaya into the haor basins, vast stretches of ripened boro fields are now submerged under water. While public attention has focused on the immediate threat to rice production, an equally serious but less visible risk is emerging beneath the surface, the growing threat to aquatic life, particularly fish population, which may face stress or mortality if current conditions persist.

The haor region, composed of 373 wetlands, is not only a major rice-producing zone, accounting for nearly 18 per cent of Bangladesh’s total rice, but also a vital fisheries hub. According to the Fisheries Resources Survey System, the haor fisheries sector produced 128,378 tonnes of fish in the 2023–24 financial year. For millions of people, these wetlands are both a source of food security and livelihood. Yet this ecological balance is now under pressure.

As of April 28, only about 50 per cent of the total boro harvest has been completed across the haor districts. The situation varies across regions: Sunamganj has achieved roughly 44.5 per cent harvest, Kishoreganj about 48 per cent, Habiganj approximately 53 per cent and Netrakona between 55 per cent and 62 per cent. Across the wider Sylhet region, around 56 per cent of cultivated land has been harvested. This leaves a significant portion of fully ripened paddy still standing in the fields, now submerged under rising water.

The reasons behind this incomplete harvest are interconnected. Persistent pre-monsoon rainfall, combined with early runoff from Meghalaya, has inundated fields before harvesting could be completed. Modern combine harvesters are unable to operate in muddy or flooded terrain. At the same time, farmers face labour shortages, rising wage costs, high diesel prices and fuel constraints. Frequent lightning has further restricted fieldwork, while submerged traditional drying yards (kholas) have disrupted post-harvest processing.

While the scale of crop loss is severe, focusing only on agriculture risks overlooking a cascading ecological concern. Submerged paddy fields do not simply represent lost harvests, they can become large masses of organic material decomposing underwater. As rice plants rot, microbial activity increases, consuming dissolved oxygen in the water. At the same time, decomposition may release ammonia and other byproducts, altering water chemistry and potentially lowering pH. Together, these changes can create stressful conditions for aquatic organisms.

Fish, which depend on sufficient dissolved oxygen levels, are particularly vulnerable. Prolonged stagnation combined with high organic load can lead to oxygen depletion, forcing fish to migrate where possible, or suffer stress and mortality. However, such outcomes depend on the extent and duration of submergence, water movement, and overall hydrological conditions within the haor system.

This is not merely a theoretical concern. During the early flash flood of 2017 in the haor region, similar conditions were observed. Large areas of unharvested boro paddy were submerged and subsequent decomposition contributed to water quality deterioration. Reports from that period indicated abnormal ammonia buildup, declining dissolved oxygen levels, and shifts in pH, ultimately resulting in mass fish mortality across several haor systems. The parallels with the current situation are difficult to ignore.

What makes the present situation more concerning is its recurrence. Early flash floods, once considered occasional anomalies, are becoming more frequent and less predictable. This reflects broader climatic variability and intensified rainfall in upstream catchments, particularly in Meghalaya. The haor system is highly sensitive to such hydrological changes, yet preparedness measures continue to focus primarily on crop protection, often overlooking the interconnected aquatic ecosystem.

The implications are significant. Farmers risk losing their annual  rice harvest, while fishing communities may simultaneously face declining fish stocks. This combined shock, agricultural and fisheries loss, can undermine food security, income stability and rural resilience in the region.

It is, therefore, important to recognise that this is not only an agricultural disaster, but an ecosystem-level risk. Managing haor conditions requires an integrated approach that considers both crop production and aquatic health. Early warning systems based on upstream rainfall data must be strengthened. Rapid harvesting support — through coordinated labour deployment and appropriate machinery — should be prioritised before peak inundation. Equally important is real-time monitoring of  water quality parameters such as dissolved oxygen, ammonia and pH to assess ecological risk.

The events of 2017 served as a warning. The unfolding situation today suggests that the lesson remains only partially absorbed. If submerged paddy continues to decompose under stagnant water, conditions may develop that threaten aquatic life, including  fish populations. In this context, the Department of Fisheries and relevant officials should remain alert and prepared. Proactive monitoring, early detection of water quality deterioration and rapid response planning could help reduce ecological damage. While fish mortality is not inevitable, the risk is real and preparedness now may determine whether the haor ecosystem faces another avoidable crisis.

Iftekhar Ahmed Fagun is a lecturer in fisheries resources and management at Habiganj Agricultural University.

Published Date: May 3, 2026