Health and sustainable development

Slum upgrading

A cable car suspended above a street in Medellin, Colombia.
A cable car suspended above a street in
Medellin, Colombia
Jorge Gobbi/Flickr Commons

Slums are home to an estimated 828 million people, representing around one third of the world’s urban population. In some developing cities, the slum population can reach up to 80%. Hence, informal settlements that result from unplanned growth offer unique opportunities for city planners to achieve improvements in both climate and health.

Many current slums are vast islands of informal economies, social exclusion, poor housing and underdevelopment. Smart, productive cities of the future can transform these areas into vibrant neighbourhoods that are fully integrated into urban design management systems.

Refurbishing slums with street networks, expanded green spaces, and upgraded infrastructure improves the physical living conditions, quality of life, and access to services and opportunities. It also decreases the prevalence of health risks associated with unhealthy living conditions. To achieve this, local participation can be a powerful instrument to mobilize low-income communities around the planning, management and governance issues of their neighbourhoods.

Schoolgirls walk in an alley of a densely populated<br>Kampung neighbourhood where sewers were built,<br>and then alleys pedestrianized as part of a<br>slum housing upgrade programme in Indonesia
Schoolgirls walk in an alley of a densely populated
Kampung neighbourhood where sewers were built,
and then alleys pedestrianized as part of a
slum housing upgrade programme in Indonesia
Jeff Kenworthy

Simple, climate-friendly housing initiatives in slum areas have included innovations such as: roof insulation; installation of rooftop solar hot-water heaters; PV solar panels for lighting and grid electricity backup; improvements in piped drinking-water and sewage infrastructure; and the creation of pedestrianized corridors in narrow alleyways to keep out motorcycle traffic, reduce noise, and protect children’s safety.

One new innovation in sustainable transport in rugged mountainside Latin American “favelas” has seen the creation of airborne cable cars, or gondolas, to improve neighbourhood connections with the downtown area – thus improving access to jobs, education and services. Rio de Janeiro, Brazil, Medellin, Colombia and Caracas, Venezuela, and La Paz, Bolivia have been among the early adopters of this clean, quiet and efficient transport mode.

Clean household cooking and heating sources in urban areas may include the replacement of coal and low-efficiency biomass stoves with cleaner fuels and technologies, such as induction electric stoves, now becoming more accessible in cities of South Asia, liquefied petroleum gas (LPG), which is generally more available in the city than countryside; or industrially produced renewable fuels such as ethanol and biogas. WHO estimates that annually 4.3 million people die prematurely from illnesses linked to household air pollution, primarily from stroke, cardiopulmonary illnesses, acute and chronic respiratory disease, and certain cancers.