Concrete consequences: Dhaka is now an urban inferno

Dhaka's temperature is rising at an alarming rate, with experts pointing to a lethal mix of haphazard construction, vanishing greenery, and environmental degradation.

Once breezy corridors of airflow are now obstructed, giving rise to a string of urban "heat islands" that render the city ever more perilous.

This year’s Earth Day—marked globally and across Bangladesh on Tuesday (22 April) - carries the theme "Our Planet, Our Power". 

In Dhaka, however, that power appears to be waning in the face of environmental mismanagement.

Urban planner and President of the Bangladesh Institute of Planners (BIP), Professor Adil Muhammad Khan, observed, “Much of Dhaka has transformed into heat islands. Our concrete footprint continues to expand. Where once stood modest five- or six-storey blocks in Azimpur, there are now towering concrete monoliths. As buildings mushroom, open spaces vanish, intensifying heat and risk.”

A 2021 study by the Bangladesh Red Crescent Society identified at least 25 hotspots in Dhaka as heat islands. Experts now suspect that number has surged significantly. While global temperatures have risen by 1 to 1.5°C, certain parts of Dhaka are heating up by as much as 5 to 7°C.

Last year’s intense heatwave caused widespread suffering among Dhaka’s residents.

A seminar titled “Heatwaves in Dhaka: Urban Planning and Development Accountability” cited myriad causes: excessive concrete, climate-agnostic building designs reliant on glass and air conditioning, filling of ponds and canals, destruction of green spaces for unplanned development, and a lack of urban forestry.

Further compounding the crisis are narrow streets flanked by high-rises, and public and private encroachment upon wetlands, reservoirs, and greenery.

Add to that the relentless air pollution from landfills, kilns, vehicles, and factories—and the city’s temperature climbs steadily.

According to the BIP, concrete coverage in Dhaka grew from 64.99% in 1999 to 77.18% in 2009, and reached 81.82% by 2019.

The institute’s 2023 research revealed that over the past 28 years, the capital’s green space has shrunk to just 9%, with wetlands reduced to a meagre 2.9%—far below the urban planning standards which recommend at least 25% green and 10–15% wetland coverage.

The Food and Agriculture Organization (FAO) states Bangladesh loses forest at an annual rate of 2.6%, nearly double the global average. Ideally, 25% of the national territory should be forested to maintain ecological balance.

Meanwhile, a 2022 USAID survey reported that tree coverage is only 14% in Dhaka North City Corporation and below 10% in Dhaka South—well short of the 30–40% needed in urban environments.

Illegal constructions are also to blame, according to several experts.

In response, Dhaka North City Corporation had initiated limited tree plantation and water-spraying programmes.

When asked about further plans, Mohammad Abul Kashem, supervising engineer for Environment, Climate, and Disaster Management, said, “Our routine operations are ongoing, but there is no confirmed new initiative at this point.”

Public relations officer Mokbul Hossain added, “We operate 10 spray machines twice daily to reduce dust and pollution. Our tree-planting continues, and we’re focusing on large trees for faster impact. With the monsoon approaching, further plantation drives are planned. Rooftop gardening is also being encouraged.”

To combat the rise in temperature, Professor Khan urged a shift in approach: “According to climate adaptation strategies, we must prioritise urban afforestation, restore wetlands, rebalance concrete with greenery, and cease high-rise construction along narrow lanes. Simultaneously, effective action is needed to rein in air pollution.”