Greening the megacity: Ideas from the front line

In Johannesburg, bus rapid transit (BRT) represents a lot more than it does in most cities. In most cities it is an effective technique for getting residents to and from work faster with fewer carbon emissions during congested rush hours, a technique that was spearheaded in Curitiba, Brazil, and now copied in cities worldwide.

While decreasing gridlock and improving air quality are welcome co-benefits for most cities, the BRT is fulfilling a much deeper, more powerful, even healing role for Johannesburg.

A primary driver for Parks Tau, the city’s mayor, for developing the Rea Vaya BRT is to address the legacy of apartheid planning. He calls the BRT lines “corridors of freedom” to emphasise their role in re-stitching separated parts of the city back together, providing a physical means to overcome apartheid era barriers caused by physical space. Transit-orientated development around the Rea Vaya stops are providing new homes, and importantly local day-to-day amenities for communities that once had none and leading to the social integration that is the face of the new Johannesburg.

This is just one of many incredible stories heard at the C40 Mayor’s Summit that took place in Johannesburg on 5-6 February. The summit brought together mayors, or their deputies, their chiefs of staff, their sustainability directors and environmental aides to the biannual meeting of megacities taking action against climate change. The primary role of the C40 is to facilitate cities to learn from and be inspired by each other on how to reduce their contribution to climate change.

While decreasing gridlock and improving air quality are welcome co-benefits for most cities, the BRT is fulfilling a much deeper, more powerful, even healing role for Johannesburg

The Global South, it seems, can bring lessons to the Global North. Not only is Johannesburg introducing BRT ahead of many US cities (many of which could also benefit hugely from more social integration); it is also starting an ambitious programme to harness energy from its wastewater treatment plants.

The first MW of power from anaerobic digesters is on-line at one of the city’s six waste water treatment plants (WWTP), providing 15% of the power needed to keep it running. In time, additional CHP engines will provide around 50% of the power required.  (Who knew that to treat sewage took so much energy?) This technique has only become cost effective since electricity prices increased 30% in three years (due to growth in the demand for electricity in South Africa not matching supply) giving the system a palatable six to seven year payback. 

Many cities in the US still are flaring (squandering) gas that could be supplying low carbon energy.  Until the true cost of coal and oil generated electricity is realised, this is unlikely to change.

Has composting your food waste changed the way you shop? It should. Experiencing the weight of the biodegradable bag containing the uneaten and gently molding kale, hard cheese and blackened carrots should make the western world shop more wisely, and save money, because of experiencing the waste of composting uneaten food. Another win-win.

This story, shared by Oslo, came from some of the 72,000 residents that the City talked to during a door knocking campaign about their composting program. This story was shared after the Mayor of Johannesburg explained that many of his residents spend 65% of their income on food. (The amount of food left over after the Summit lunches did not make this attendee feel good. I hope it went to reduce the weekly food bill for some locals.)

While some cities continue to pursue single-stream recycling, educating their residents to sort into different coloured bins, Houston gave an update during the summit on its plans to commission a single-stream waste facility that will sort co-mingled waste, diverting an estimated 70% from landfill. Houstonians will be able to go back to the good old days of throwing everything in one bin. Other cities – from the North and the South – will be watching with great interest.

The ex-mayor of New York, Michael Bloomberg, was front and central at the Summit, handing over his chairing role to mayor Paes of Rio de Janeiro, who appears to have the energy and passion to keep things going. He has a hard act to follow, though. Without a doubt, Bloomberg, through his drive, leadership and incredible philanthropy, has changed the face of climate action in cities and through the C40 has helped the world of global climate negotiations recognize the importance of cities.  

It was particularly poignant that the mayor of Rome was unable to join a discussion on climate adaption due to flooding causing a state of emergency

Indeed, Christiana Figueres, executive secretary from the United Nations Framework Convention on Climate Change (UNFCCC), gave a keynote speech at the summit, emphasising the importance that the global climate change community is now placing on the future role of cities in helping to solve the climate problem. If you were to combine the C40 cities into a country, it would have the third largest GDP and population size in the world. COP 19, held in Warsaw, was the first time that the voices of cities were formally heard at a global climate negotiation. They will be again in 2014 at COP 20 in Lima.

While climate mitigation – the act of reducing the production of greenhouse gas emissions – was a critical part of the discussions, resiliency and adaptation were too. As California faces another year of drought (declared by the governor on 17 January, with the snow pack 12% of normal), New Orleans was seeing snow, the North-east of the US was locked in a polar vortex and much of the UK is under water both from heavy rain swelling rivers and coastal storm surge, it was particularly poignant that the mayor of Rome was unable to join a discussion on climate adaption due to flooding causing a state of emergency. Much still to do.

Claire Bonham-Carter is a principal and director of sustainable development, design and planning at Aecom