Precision farming must go hand in hand with groundwater protection

Résumé détaillé

The government should judge precision agriculture not simply by yields or sensors installed, but by whether farming remains productive without exhausting groundwater.…

BNP had promised in its election manifesto to bring precision agriculture to Bangladesh. The idea is to use sensors, Earth observation, and other data to provide crops with the right amount of water, fertiliser, and other inputs at the right time. With a growing population, shrinking farmland, and a changing climate, growing more food from what we already have is a national priority. But such ambition must also ensure the protection of groundwater, which has been the backbone of farming progress in Bangladesh.

Shallow and deep tube-wells made widespread rice cultivation possible in the dry season. Today, roughly three-quarters of irrigated dry-season arable land, especially paddy fields, relies on groundwater. In parts of the northwest, however, decades of pumping have been accompanied by falling groundwater levels.

Precision farming can help an individual farmer decide when and how much to irrigate. But saving water on one farm does not necessarily reduce pumping across an area. If the savings allow more land to be irrigated or another crop to be grown, overall withdrawals could remain unchanged or increase. The larger question is about how much groundwater can be used, where, and when, without undermining future supplies.

Answering that question means understanding aquifers: the underground layers of sand or rock that store and transmit water. Their capacity to supply water depends on geology, how water is released from storage, and how it is replenished by rainfall, rivers, or neighbouring layers. Conditions can differ between villages and even between shallow and deep aquifers beneath the same area. In some shallow aquifers, dry season pumping lowers the water table, leaving more space for monsoon water to infiltrate. Where infiltration is favourable, this seasonal cycle can increase the volume stored underground. But space does not guarantee replenishment.

The Barind region provides a stern warning. In some places, pumping has lowered groundwater pressure until…

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