Are road diets the next big thing for US cities?

Does Chicago really need all those lanes? Image: Getty.

Like so many new concepts in urban planning, road diets seem like a great idea at first. And, like so many concepts in urban planning, they tend to generate a lot more criticism once they’re put into place.

The idea of a road diet is simple: to pinpoint streets that have excess capacity and could be narrowed down without significant car congestion, so providing space for other uses, such as sidewalks and bike paths.

It’s also an almost exclusively American concept, which makes sense; while streets in Britain and other European countries aren’t exactly crying out to be narrowed down, on the other side of the Atlantic, the streets seem to be the only thing wider than the country’s waistlines.

The roots of the concept date back to the 1970s, but it only began gaining traction over the past decade, loosely connected with other movements such as smart growth and complete streets.

Planners in the US began studying cases in which city streets had been widened to improve traffic flow for cars. They found that, in most cases, these projects did little to improve traffic flow, while creating an enormous increase in accidents. For instance, a study done in Fort Madison, Iowa, showed that while widening a main road led to a traffic volume increase of 4 per cent, it also increased the accident rate 14 per cent, and the injury rate by 88 per cent.

The obvious response to these findings is, naturally, to slim wider streets back down. But this slimming down can take many forms: widened sidewalks; replacing four-lane highways with three-lane ones, in which the middle lane is for those turning; and separated bike lanes. Last year, urban planner and author Jeff Speck teamed up with animation specialist Spencer Boomhower to create a series of videos showing the many possible forms road diets can take.

How effective has the concept been? In the US, road diets have seen a number of success stories. In New York City, a 2013 study revealed that road diets there had “significant safety benefits”.  They’ve seen success on the west coast, too: a pioneer in road diets, San Francisco has implemented 34 road diet projects over the last four decades, with favourable reactions from traffic engineers. Similar projects have also been implemented successfully in nearby Davis, California.

A street in Davis, CA, before its road diet. Image: Transport Observer/Wikimedia Commons.

But though road diets have allowed some cities to slim down their traffic safety problems, others have found that sticking to road diets is harder than sticking to actual diets.

Take Carolina Beach, North Carolina. Back in 2010, planners implemented a road diet on Lake Park Boulevard, one of the city’s main thoroughfares, in a bid to make the city more bike friendly.

But the measure was met by howls of protest. Local businesses complained of decreased sales, and the city’s car traffic during holidays led to increased traffic jams. In 2012, the road diet was reversed.  

Down the coast, in Gainesville, Florida, a road diet was adopted in mid-2013 for a wooded stretch of 8th Avenue. Four traffic lanes were reduced to two on a trial basis.

While the trial decreased injuries significantly, it met with staunch criticism from drivers, inconvenienced by a difficult merge area created by the road diet. The new configuration remained for over a year, but it was finally removed after being voted down by the city commission in December 2014, though plans are in the works for adding a shared pedestrian/cycle path on both sides of the road.

The same street after its road diet. Image: Transport Observer/Wikimedia Commons.

Then there’s Los Angeles, which despite some noble efforts to reverse its car-centric status by expanding its metro system, lives up to its reputation in its efforts to pursue road diets. Back in 2011, an attempt to implement a road diet on Wilbur Avenue, deep in the depths of the suburban San Fernando Valley, was quickly put to sleep after massive neighbourhood outcry.

Even in Silver Lake, an LA neighbourhood packed with bike-loving hipsters, the policy is in trouble. A road diet on Rowena Avenue in place since 2013 has been the source of continuous controversy, including angry driver rants caught on tape, though it remains in place for the time being.

Though the reasons road diets fail vary city by city, their common underlying cause boils down to political convenience. By their nature, road diets create an immediate inconvenience for drivers – who tend to be more affluent and politically connected; to compensate that, there’s only the long-term promise of creating greater safety, and a more bike and pedestrian friendly urban environment. For local politicians eager for quick victories, this all too often proves to be a toxic combination.

The lesson is clear. Road diets have paid off for some US cities. But for others, powerful political forces and a deeply rooted car culture have made sticking to road diets as difficult as swearing off junk food.


In Quito this week, the world is meeting to discuss the future of its cities

The 'La Compania' church, in the historical centre of Quito, is illuminated during a light show held to open the UN's Habitat III Conference. Image: Getty.

As the global population grows from seven to nearly ten billion by 2050, we will need to build the equivalent of a city of 1m people every five days to house them.

The world already has ten cities with more than 20m inhabitants, including Tokyo (37m), Beijing (21m), Jakarta (30m) and New Delhi (25m). Out of the 7bn people in the world, 6.7bn live with pollution above WHO clean air standards.

And by 2050, around 12m people from 23 cities in East Asia alone will be at risk from coastal inundation. Planning for climate change will be critical to minimise risk to these areas.

These are just some of the stark facts about our global urban future.

With these issues in mind, up to 50,000 participants have gathered in Quito this week to discuss a New Urban Agenda at Habitat III – the United Nations Conference on Housing and Sustainable Urban Development.

The adoption of the agenda will set standards for sustainable development with a strong emphasis on social inclusion, cultural diversity, urban prosperity, urban governance, urban spatial development, and integrated urban planning including climate change.

From Paris to Quito

The Paris agreement on climate change will come into effect in November 2016. Cities will be at the heart of achieving its aim to limit global warming to less than 2°C. Planning for a low-carbon and resilient urban future is now our greatest global challenge. It is critical to achieving emission reduction targets and planning cities for climate change.

After all, cities produce 76 per cent of carbon dioxide emissions and account for 75 per cent of energy use worldwide.

The focus is now on implementing the Paris agreement; that is where the New Urban Agenda, proposed for agreement at UN Habitat III, comes into play. Key issues being discussed include affordable housing, urban transport, gender equity, empowerment of women and girls, poverty, and hunger in all its forms. Involving communities in the future and design of cities is essential. Better urban governance of our growing cities and urban regions is a core theme.

Observing the range of activities here at Habitat III, it is impressive to see the significant engagement of the private sector as well as governments and NGOs. This mix of partnerships is vital if we are to make positive change in the planning of our cities. Global companies are present as well as local consultancies. They can clearly see there is a market for them in more sustainable futures: that brings great hope for the future.

The scientists are less happy, and are seeking greater engagement in future discussions. The latest issue of Nature comments that “scientists must have a say in the future of cities”, and argues that they should have been more involved in the Habitat III processes. Clearly, better connecting scientists with planners with communities is important in finding sustainable solutions.

A key component in improving city planning is sharing knowledge and expertise. Cities are often connected through global urban networks such as C40, a network of megacities advocating for action on climate change, and the International Council for Local Environmental Initiatives.

Another important strategy being presented is improving the sharing of knowledge and expertise between “like climate regions”. It is equally important to improve communication of the major urban challenges with wider audiences. Researchers with the United Nations University have also developed an art strategy as part of the preparatory process for Habitat III, with the intention of stimulating thought and discussion on health and well-being in cities.

The overall message from UN Habitat III is that the sustainable planning and design of our cities and human settlements is fundamental to improving the health and well being of our urban communities and acting on climate change. Through that, we tackle the stark facts of urban pollution, our response to climate change, and the future liveability of our cities.

Our moment to act

We are living in a unique time for cities, with multiple UN agendas coming together at once: the UN Sustainable Development Goals, the Paris climate agreement, Sendai Framework for Risk Reduction and the Small Island Developing States Partnerships Framework.

National urban policies are seen as crucial to implementation of all these agreements. As the New Urban Agenda states:

the persistence of multiple forms of poverty, growing inequalities, and environmental degradation remain among the major obstacles to sustainable development worldwide.

Through better urban governance, we can make significant inroads to address the ongoing barriers to achieving more sustainable cities. The proposed agenda particularly highlights transportation and mobility as a priority to support action.

Habitat III offers an opportunity to raise global understanding of the enormous challenges facing cities, and a platform for nations to collaborate in developing more sustainable urban futures. This will require considerable effort from everyone.The Conversation

Barbara Norman is chair of urban and regional planning at the University of CanberraJohn Colin Reid is a visual artist, attached to Australian National University.

This article was originally published on The Conversation. Read the original article.