Bangladesh’s Buriganga River in South Asia wends through the country’s capital of Dhaka, home to more than 20 million people. Like many waterways that support massive populations around the world, the Buriganga is the lifeblood of Dhaka’s economy, teeming with passenger boats, barges hauling food and goods and heavy industrial production. Yet the river and its surrounding ecosystem are dying.
Extreme environmental degradation from tanneries (hundreds are unregulated), brick kilns, mills, textile production, pharmaceuticals and more choke the river. According to Bangladesh’s Ministry of Environment, about 5.7 million gallons of heavy metals and untreated chemical waste is dumped into the river each day, just from the leather tanneries alone. Most of the nine major industries lining the riverbanks don’t have sewage treatment or effluent treatment systems. The City of Dhaka releases about 4,500 tons of solid waste into the river every day – about 80 percent is untreated.
The pollution crisis promotes the uncontrolled growth of water hyacinth, which in turn obstructs and reduces the river’s flow. The Buriganga, starved of oxygen, has decimated all fisheries and every other form of marine life. Yet many citizens fish, bathe, play and wash their clothes in the blackened, contaminated waterway.
The HKS’ Dallas Design Fellowship team – Jason Fleming (HKS Houston), Lawrence Kam (HKS Singapore) and Divya Nautiyal (HKS Richmond, Virginia) – created a concept to reverse the Buriganga’s toxic course, proposing a cleaner, alternative future for the river ecosystem, the local economy and its people.
DR/EDGE is an innovative example of circular economy design at urban scale. Not only is the river’s waste, sludge and silt material being reused, recycled and remade into bricks, the existing brick kiln factory is reimagined and adapted as a waste collecting apparatus, housing, and community gathering spaces.
This Design Fellowship project was presented at the Architecture Exchange East Conference 2019. It has been recognized as a 2019 Boston Society of Architects Unbuilt Design Awards winner and secured the first award at the 2019 Global Architecture + Design Awards in the conceptual Mixed Use category.
The Design Fellowship team focused on water — oceans, seas, lake, and rivers —a significant force for community organization since the dawn of civilization. Rivers are unique in that their constant flow means any point along their banks can be affected by changes upstream and can create changes downstream. Rapid urbanization, industrialization and increasing encroachment of the river’s edge have disrupted the balance of many rivers in the form of pollution, reduction of flow, and loss of riparian and aquatic habitats, imperiling the environment and human settlements across rivers’ entire length.
In Dhaka and the surrounding region, brick making is one of the most prominent industries, producing 3.5 billion bricks annually and employing a half million people. But it is also one of its biggest polluters and impediments to river flow. The region changes dramatically with the annual monsoon season, making brickmaking impossible and leaving migrant workers jobless for half the year. Short-term financial incentives entice farmers to sell topsoil from productive farmland, cutting long-term crop yields and exacerbating runoff and sedimentation.
The production of bricks and the challenges that face the city have a real and tangible impact on people and the river. The HKS design team gauged its design response through the eyes of stakeholders at each end of the brickmaking economy.
A Waste-to-Energy Process
As it currently exists in Dhaka, the brick making process is one-directional. At the same time, the river is laced with trash and silt, both considered undesirable and worthless. HKS proposes to leverage these undesirables, capturing the sediment to replace topsoil and collecting the waste to be used in a modern Waste-to-Energy process. This reimagined system is a springboard to imagine a performative apparatus that captures raw material and serves as the foundation for programmatic layers atop and creates new landscapes for human occupation.
DR/EDGE operates in two intertwined modes: as an industrial machine that sustainably remakes the regional brickmaking industry; and a civic framework that creates new environments for community members to thrive.
DR/EDGE’s geometry scrapes garbage from the river and utilizes eddies that trap silt during monsoon season. When the water recedes, the kiln owners are left with free raw material, improving the system’s economics and incentivizing future investment. The Waste-to-Energy plant sits atop the base structure, providing employment opportunities for workers during the wet season when brickmaking goes on hiatus.
Silt and garbage also replace existing unsustainable inputs (silt in place of topsoil taken from productive farmland; Waste-to-Energy in place of coal) and reduce air and water pollution, affecting positive environmental change at the local and regional scale.
As an urban intervention, DR/EDGE is a series of performative edges that flip the problems of flow, pollution and encroachment into opportunities. But more than that, HKS created spaces for community to happen. The once-polluted river now becomes accessible and active, repairing the relationship between water and community, turning an endangered wetland into a testament to sustainability.
The introduction of civic programming and housing set in motion a transformation from seasonal migrant work to permanent, stable and secure communities. These re-imagined societies can exist on a more equitable footing with factory owners, with fellow Dhakaites and with the Buriganga River itself.
“We realized that our intervention has to be a bottom-up approach, with direct benefits to the local community and its citizens,” said HKS Design Fellowship team members Fleming, Kam and Nautiyal. “While considering the broad global applications, we focused on specific responses which not only tackles a problem but is intrinsically tied to the local economy.”
While the DR/EDGE concept is intimately tailored to Dhaka and its culture, HKS’ ambition is to tease out strategies that are broadly applicable in places that face similar challenges.