Australia has some of the most liveable cities in the world, but will these same cities be as liveable (and lovable) once their populations double? Our major cities are expected to grow exponentially over the next few decades, with Melbourne overtaking Sydney in size by 2050 as it approaches eight million residents. To put that in perspective, Australia’s major cities could soon rival the size of today’s New York or London.
Australians certainly aren’t alone in our propensity for urban growth. By the middle of this century, it’s expected that almost two-thirds of the world’s population will live in urban areas. These 6.5 billion city residents will all need homes, places to work, and ways to get around. Population growth brings more buildings, more traffic, and less space – so how do urban planners face the complexity of a growing metropolis? There are some extraordinary examples of smart city infrastructure already being deployed to protect and improve standards of living in urban areas. Let’s spin the globe to see how urban planners and engineers are tackling the most common challenges to their expanding cities.
THE URBAN HEAT ISLAND EFFECT
Australia is loved for its blue skies, but Oz’s enviable long summers will spell trouble as our cities swell in size. Major metropolises are already suffering from the ‘heat island effect’, where built-up areas trap heat from the sun and at times can be six or seven degrees higher than their leafier counterparts. This is a serious problem – in fact, it’s estimated that by 2050, Australia’s heat-related deaths could quadruple.
Vegetation cover can provide a two-pronged defence against the urban heat island effect, both through shade cover as well as the cooling effects of evapotranspiration. Established trees have additional benefits for stormwater management and air quality; a study of ten megacities found that one square kilometre of tree cover could save each city resident an average of $83 every year in costs associated with cooling, air quality management, and water runoff. Million Tree initiatives have sprung up in New York, Los Angeles and Shanghai to grow tree canopies through planting, and many Australian government areas now have their own urban tree canopy plan in place to identify and address heat stress spots. The City of Perth, for example, is aiming to increase its tree canopy from 19% to 30% by 2036.
Planners can implement cooling methods at the ground level, too. Cities such as Los Angeles are starting to apply ‘cool’ surfaces to their pavements; these surfaces are designed to be either more reflective to absorb less of the sun’s radiation, or more permeable for their moisture absorption and evaporation qualities. Of course, cities can also convert large areas of plain or paved ground to grass to help cool the surrounding area.
TRAFFIC AND CONGESTION
A boom in population inevitably leads to an increase in traffic congestion, which can affect residents’ wellbeing through pollution, stress, and hours spent in traffic jams. Urban planners tend to approach the traffic challenge through two factors: pedestrian and cycling infrastructure, and access to public transport.
Cities such as Copenhagen and Amsterdam are internationally praised for infrastructure that attracts cyclists and pedestrians to central areas. Copenhagen recently installed traffic lights that detect and prioritise cyclists over vehicles, as well as several superhighways designed solely for bicycle use. The city’s Superkilen public park was completed in 2012 and converted a formerly crime-rife area into a vibrant shared space, including cycling paths, meeting places, and picnic areas designed to celebrate the city’s diversity. Within Australia, bike share systems in Brisbane and other cities are seeing positive acceptance and adoption by residents.
Los Angeles is one city that’s particularly known for its urban sprawl, and public transport systems have seen a fall in ridership in recent years as car ownership has increased. The transport authority’s Office of Extraordinary Innovation is developing a pilot program called MicroTransit that would see multi-passenger vehicles offer direct pick-ups and drop-offs from passengers’ homes on a non-fixed route. As it would be cheaper than ride-hailing services and more convenient than existing public transport options, this tailored type of transport solution has the potential to take vehicles off the road and reduce congestion in a city where cars have long been the go-to option.
Pollution is a direct result of high traffic and high-density areas, and its effects on health and quality of life are well-documented. Smog is linked to a staggering 31.8% of deaths in China, and takes more than two years off the average life span within the country. In an effort to reduce the impact of pollutants, China will soon see its first ‘forest city’ in the industrial city of Liuzhou. This design will incorporate one million plants and 40,000 trees spanning 100 different species. It’s estimated that the green city will absorb almost 57 tons of pollutants and 10,000 tons of carbon dioxide, while producing 900 tons of oxygen each year.
In Mexico City, planners have utilised highway pillars to create vertical gardens complete with rainwater hydroponic systems to improve air quality and sound insulation from traffic. The project is expected to capture around 10 tons of heavy metals per year and produce enough oxygen for over 25,000 citizens. In Hong Kong, over 400 ‘smart’ lampposts are to be installed to track weather, pollution, transportation and crowd flow. The data collected from these lampposts will be used to optimise public services and transport options. Meanwhile, Melbourne has approved a promising policy to install 2,000 car share spaces throughout the city by 2021 with the aim to reduce residents’ reliance on private car ownership. There’s also a new partnership between the South Australian government, the City of Adelaide, and Cisco that will see the use of traffic sensors and tailored algorithms to ease congestion and make way for autonomous vehicles.
ACCESS TO SHELTER FOR THE HOMELESS
Every growing city will face the issue of how to assist its homeless population. While long-lasting solutions to homelessness are typically complex, there are a number of innovations that could provide temporary shelter, security, and privacy for those who are living on city streets. In Melbourne’s inner west, a partnership between Launch Housing and the Department of Health & Human Services has been formed to install 57 transportable homes on an unused VicRoads property. These complete homes have been designed to a six-star green rating and can be moved to an alternative location as the land is needed.
Homelessness is also a problem in New York, which experienced a 4.1% increase in homelessness in 2017 alone. The city is expecting to spend around $384 million each year for the next three years to house the homeless in commercial hotels. While the city’s mayor has a strategy in place to build more shelters and convert hundreds of private apartments, temporary measures could be beneficial. Innovation studio Framlab, for example, has proposed a system of hexagonal pods that can be stacked in a honeycomb configuration against a scaffolding structure. The project, called Homed, could provide temporary refuge for vulnerable people in a space-efficient design that makes the most of the city’s vertical spaces.
RISING CITY SKYLINES
Urban planners will often plan cities ‘up’ rather than ‘out’ to avoid the congestion and pollution that’s associated with urban sprawl. However, managing a city’s skyline should be an important consideration for several reasons. By 2020, 5G networks are set to transform the connectivity of our cities, promising speeds of up to 100 times the current 4G telecommunication networks. These new 5G networks use millimeter wave spectrum bands that travel short distances and cannot penetrate easily through walls or other objects, so a clear line of sight is required between transmitter and receiver for the best signal. Urban planners and network engineers are turning to 3D data sets created derived from aerial imagery when assessing buildings and other infrastructure to ensure that walls, vegetation, and street features will not interfere with these networks as they are rolled out. Real-world 3D modelling has additional applications for safety planning, including identifying rescue access points, sniper placement, and the positioning of surveillance cameras.
City skylines are carefully accounted for in larger cities such as San Francisco and more recently in London, where city plans established protected views or ‘sightlines’ that ensure iconic landmarks remain visible. While this can occasionally cause frustration for real estate developers, it’s a democratic design decision that can give residents a shared sense of ownership and pride. It also improves tourist appeal, which are vital to a city’s growth and sustainability; tourists can thank the foresight of London’s urban planners as they gaze upon St Paul’s Cathedral from King Henry’s Mound.
Building the right infrastructure for sustainable cities urban growth is a challenging task, but we have more sophisticated tools and techniques than ever before to ensure our urban areas can support their burgeoning populations. Using all the research systems, data, and innovative engineering solutions at our fingertips, we can work to improve our standard of living and ease the growing pains of the world’s largest cities.