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Making cities sustainable

January 07, 2019

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The writer is a PhD student in urban/regional planning at the University of Illinois.
The writer is a PhD student in urban/regional planning at the University of Illinois.

ONE good thing to emerge in recent months is a concerted discussion on the environment, climate and sustainability: Pakistan now has a dedicated focal person on climate change, water stress has dominated the headlines in recent months, and discussions around smog and air quality have garnered national attention.

There is no question about the critical position we are in today. We are energy- and resource-starved, and changing climatic conditions are harbingers of tougher times to come. To make things worse, our cities magnify problems of extreme temperatures, flooding, and pollution due to an improper built form, inefficient consumption patterns, and flawed or absent planning and regulatory regimes. Our cities are not sustainable: we would fail to leave anything (let alone enough) for our future generations at the current consumption and resource-generation levels.

Consider water, for example. All of our major cities are in the midst of moderate to severe water crises, and groundwater levels have gone down across the board. Part of the crisis is due to excessive pumping for domestic, commercial and other use, and wasteful practices like washing cars using fresh running water. The other part, directly linked to the built form of cities, is because of the lack — or even complete absence — of opportunities for groundwater recharge in urban areas.

Cities must act to bring work, shopping and living in close proximity to one another through multipurpose developments.

The quality of an area’s groundwater and how we use and conserve it is directly connected to its built form. Urban areas typically have lots of concrete — think paved roads, buildings, and parking lots. These surfaces do not allow water to seep through to the ground, leading to higher levels of surface run-off. Groundwater levels continue to recede in such areas, as has happened in Pakistan, as cities keep pumping out more water than is recharged.

Paved surfaces that do not allow water to pass through also directly impact the quality of a city’s water supply. Because water cannot seep through road and other concrete surfaces, it washes off along the slope, often entering the city’s sewerage and drainage system, and ending up in streams and other water bodies. This surface run-off includes toxic chemical compounds such as engine oil and petrol deposits washed off road surfaces, or paint washed off buildings.

Concrete and paved surfaces also create other environmental complications in cities. They absorb heat and radiate it back into the surroundings. Additionally, air-conditioning systems in buildings push hot air out into the open, and fumes from vehicular traffic are significantly higher around key road corridors. Together, these factors contribute to smog and to the ‘urban heat island’ effect, due to which temperatures in cities are several degrees higher than the natural temperatures in surrounding areas.

These environmental problems are compounded in suburbanised, car-centric development models like ours. Urban sprawl results in more impervious surfaces, leading to groundwater depletion and the heat island effect across larger areas. Because of lower population densities across large areas, sprawl also creates other inefficiencies in service provision, commuting habits, and resource allocation.

Most research today has established a general consensus that sprawled, suburban models of single-family housing are the most resource-inefficient, energy-intensive, and, therefore, unsustainable models of urban development. Unfortunately, cities in Pakistan seem to be headed in the exact direction that planners have now come to dread.

It is imperative that we completely rethink our cities and urban spaces to encourage environment-friendly, sustainable development practices. Take the example of water again; we must cut down on impervious surfaces in cities to allow rain and other surface water to seep into underground aquifers and replenish our dwindling supplies of groundwater. Both new and old developments must include adequate green spaces and facilities like rain gardens, retention basins, and detention ponds that capture rainwater and allow it to filter underground, instead of washing away into the city’s drainage systems.

These requirements should especially apply to the hundreds of privately developed housing societies that have mushroomed in cities across Pakistan. Most of these developments fail to comply with the very basics of planning, and overburden our cities’ already crumbling infrastructure. Every private development must be mandated to deal with all storm water and floodwater onsite, without using the city’s sewerage or drainage systems, or polluting rivers and streams. Additional requirements for green space, permeable surfaces, and the facilitation of mass transit must also be imposed.

Perhaps most critically, we must take drastic steps to multiply existing densities in urban areas and completely discourage the single-family model of housing. Archaic zoning rules that restrict building heights must be revisited to conform to new planning principles that encourage sustainable development. Cities must act to bring work, shopping, and living in close proximity to one another through multipurpose buildings and developments. Commute must not mean driving in private cars anymore, but instead should include transit, bicycles, and walking.

The development of functional transit systems is critical to building sustainable cities that future generations can survive in. The follies of car-centric cities and the direct and indirect costs they carry are now well acknowledged around the world, and it is no secret that governments effectively subsidise the use of private cars by providing free or cheap infrastructure and ignoring the social and environmental costs of car usage. Our experience with bus rapid transit, or BRT, projects should make it abundantly clear that even the capital costs we associate with transit are mostly rooted in a desire to preserve road space for cars.

With an unflinching focus on sustainability, we must move to impose the full private and social costs of urban sprawl on the developers and consumers who create it, and the full private and social costs of driving on those who insist on using private cars for everyday commute.

The writer is a PhD student in urban/regional planning at the University of Illinois.
faizaanq@gmail.com
Twitter: @faizaanq

Published in Dawn, January 7th, 2019