Dholavira, a 4,670-year-old city with perpendicular streets, planned urban spaces, groundwater and wastewater management has been recognized as a World Heritage Site by UNESCO In 2021. Hundreds of these planned cities are spread across the Indian subcontinent.
India’s ancient urban heritage, which has developed over centuries, offers many lessons in the era of deteriorating climate change. The notion of “vernacular urbanism” – i.e. cities and settlements that respond to local weather and climate patterns – is recognized by academics and the construction industry. The ancient cities of India have a lot to offer for urban development in the twenty-first century.
Urban development in the twentieth century was characterized by urban sprawl and the nucleus of the high-rise city. Cities expanded up and down. Urban experts from Patrick Geddes to Lewis Mumford to Jane Jacobs, have admitted that suburbs and high-rise city centers are unsustainable. It has a massive ecological footprint, water management problems, and problematic transportation systems, along with the poor quality of life it provides to the majority of citizens.
The United Nations Sustainable Development Goals, the invention of the twenty-first century, refer to what has already been achieved in a pre-industrial city. The primary characteristics of a traditional city in India are its compact form with non-motorized transit systems, which reduces wasteful consumption of resources and high pollution loads that contribute to climate change. It is a built form that has been perfected over hundreds of years. Indian cities such as Shahjahanabad (which became Delhi), a lively city planned and built in the seventeenth century, as well as many other traditional cities in the global south, demonstrated exactly the features that the United Nations Sustainable Development Goals strive to achieve.
Old compact cities take up less space than modern megacities as many are built on high geographic points, often resulting in high – but not high – density of living, good public transportation networks, and mixed-use areas that combine work, home and play in one area. Their hilltop locations reduce the extent of the infrastructure, both physical and social, and in the modern context reduce the demand for electrical and electronic systems. The resulting savings in fossil fuel consumption and overall capital investment contribute to climate resilience.
Before the term was invented, ancient cities had already embraced mixed-use zoning. The compact city reduces commuting distances and provides nearby recreation spaces. Transport systems within old cities are usually well shaded pedestrian networks, which also ensure the flow of cooling air. Shaded streets double as open spaces where children’s play is the “street eyes” of the family.
The old town often incorporated into larger institutional buildings on higher ground while being connected by lines of movement in the valleys. These large institutional buildings automatically generate public open spaces in front of them, serving as the distribution center for the natural air flow. In the hot arid regions of India, the constant air change improves the microclimate and has brought about a necessary change of air during the epidemic.
The value of low-high-density development is now well recognized by leading academics and urban designers such as Léon Krier, Charles Correa and Jan Gehl as being more sustainable compared to urban sprawl or energy-intensive tall buildings – high-density forms. The epidemic made matters worse as viral movement through elevators and vertical channels found free flow. Closed glass windows and recirculated air from HVAC systems exacerbated the viral cycle further.
Post-pandemic, low rise – optimal development density (optimum density varies from culture to culture, and from climate to climate) is likely to regenerate, not only to tackle the pandemic but also as a more energy efficient city, anthropomorphic scales shape. Old settlements are often distinguished by pedestrians from four to five stories. These contribute less to urban temperature rise as the heat-absorbing surface area of the building mass is significantly reduced.
Modern building materials – from production to consumption to waste – are undoubtedly unsustainable. Steel, glass, aluminum and plastics have huge impacts in mining and are very energy consuming in their production. It also involves long-distance transportation based on fossil fuels. But these are, at present, “ordinary materials” for construction.
The enormous energy embodied in modern materials is multiplied by the energy needed to maintain, cool and heat them. Traditional and organic building materials such as timber, clay and straw use very little energy to form, and therefore have a much lower environmental footprint than materials such as steel and concrete. Local materials are sourced from short distances with minimal transportation costs, built in pressure-based building systems with minimal steel and without a global supply chain. The resulting aesthetic has also been mediated culturally through centuries of building traditions.
If the construction industry’s contribution to carbon emissions, currently installed, is reduced by 40 percent, the only solution would be to humanize the building volume.
Nowadays, local settlements of thousands of square meters are neglected all over the world. Meanwhile, new developments are aggressively acquiring more and more land to expand the city. Renovation and conditioning of neglected housing stock in old towns can lead to a great deal of the built form of high thermal comfort. That would mean nearly zero additional carbon footprint.
It would be a strong call for the capital-hungry construction industry to rein in its reinvention. But the climate crisis is now largely non-negotiable. Urban design thrives as a discipline in the three-dimensional studies and simulation of climatic variables in the shape of a city. Rediscovering ancient cities is a potential direction for a climate-friendly future.
KT Ravindran is a Visiting Professor at NITTE University, Mangalore, India. Former President, Dean, Urban College of Planning and Architecture Delhi; Emeritus Dean and Senior Academic Adviser, RICS School of the Built Environment. The author has no conflict of interest to declare.
This article was republished in the wake of heat waves in India, China and Europe. It debuted on March 11, 2022.
Originally Posted under creative commons by 360info™.
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