A few years ago, I was stuck in hellish Sydney traffic, with the temperature soaring close to 40 degrees Celsius, and as I entered the tunnel surrounded by huge walls of concrete, pollution and heat haze and I suddenly thought, ‘this is a great place for plants.’
It sounds crazy, but the right plants combined with the right technology could do wonders for this harsh urban infrastructure, and science, investment and pure necessity are all at the perfect meeting point to make it viable – and perhaps essential – to turn it into ‘living infrastructure’.
Opportunities for living infrastructure are everywhere. Catching the train, I looked out the window and saw massive amounts of unused, dirty harsh spaces along railway lines. On the bus, I could see roads, bus shelters and highway overpasses – no end of blank, harsh, ugly environments that could benefit from plants and be transformed into active living infrastructure in the truest sense.
Travel around Australia and it’s clear to see we’re in the midst of an infrastructure boom. The federal government has allocated $50 billion to infrastructure, and NSW alone is in the midst of a $20 billion infrastructure spending program.
The question is, how much of that infrastructure investment will be in living infrastructure and what difference would plants and technology make to those environments?
1. From heat island to green sink
Have you ever seen those shots taken by thermal imaging cameras of a city environment on a hot day? Hard surfaces like concrete and bitumen reflect a lot of heat, making a hot day even worse and having an impact on the temperature of a city as a whole. It’s something known as the urban heat island effect.
Heatwaves have the power to kill. During the 2003 heatwave in Europe, 70,000 additional deaths were recorded, (making it one of the region’s deadliest natural disasters of the last 100 years), and in Australia extreme heat events have been responsible for more than the combined total of deaths from all other natural hazards. This becomes particularly concerning when you consider that the urban heat island effect makes city dwellers even more vulnerable to the dangerous effects of extreme weather events like this.
The challenge is that much of our existing city infrastructure is lined with concrete (think sound barriers, tunnels, bridges, tunnel entrances) and bitumen with little to no vegetation. All of these surfaces reflect the heat and as such they serve to exacerbate the urban heat island effect across a city sending temperatures to unbearable levels. In Australian cities, this is particularly concerning.
But what if we flipped it? What if we turned these hard, reflective surfaces into living walls, rather than concrete ones? What if we found ways to incorporate plants, whilst still ensuring the functionality required for such infrastructure? This would have a dramatic effect on the temperature of these environments, making it better for people using them, and also reducing the heat reflection returning to the city.
2. From exhausts to air filters
According to the World Health Organisation (WHO), air pollution is now the world’s largest single environmental health risk with some 3 million deaths a year linked to exposure to outdoor air pollution.
You don’t have to be a rocket scientist to realise that motorways carry a lot of vehicles, and vehicles equal pollution. The harsh environments surrounding these places do nothing to reduce that pollution. Instead they basically collect and intensify it, and then when it rains, this runs off into storm water.
What if we lined our motorway tunnels with plants? It sounds crazy, but it’s possible. These environments are lit, and there are numerous plants that could survive in these environments. Better still, what if we lined the tunnel extractors with plants? Those plants could then naturally clean the air before it enters the surrounding atmosphere. And then what about the harsh environments surrounding roads, rail, bridges and carparks? What if these became the green lungs of the city, sucking up the pollution, cleaning the air, filtering and even harvesting and using storm water?
What if we went from this:
3. From deserts to oases
Let’s face it, apart from a few rats and cockroaches, most urban infrastructure is not really a great haven for wildlife or nature in any form. It’s also not exactly conducive to calm happy human behavior either – think road rage, stressed drivers, unsociable behavior along train lines, the list goes on.
If we put plants in these environments and transform our infrastructure into living infrastructure, it will not only work to improve biodiversity within our cities by encouraging insects, birds and other wildlife, it would also improve human behaviour. If humans are surrounded by plants and nature, the theory of biophilia kicks in, serving to create a calming effect, leading to less aggressive behaviour, reduced stress and an overall sense of well-being giving our infrastructure an additional social aspect beyond the purely functional.
What’s stopping the integration of green into infrastructure?
If we take the term ‘infrastructure’ at its most literal definition, it refers to ‘the fundamental facilities and systems serving a country, city, or area, including the services and facilities necessary for its economy to function.’ So if these facilities, or infrastructure, are supposed to serve our country, then it’s essential that they are active and positive as well. Surely part of their service should be to serve in mitigating climate change and reducing urban heat island effect, cleaning the air and improving well-being and biodiversity?
With advances in science and technology, combined with practical experience, we’ve proven that you can grow plants on a whole range of surfaces – from multi-storey buildings to indoor environments, to harsh landscapes. Living infrastructure is gaining momentum across the world, but to date, the integration of plants with hard infrastructure such as roads, rail, carparks and bridges is limited.
Cost and maintenance are a barrier that is often raised when it comes to living infrastructure, but if you worked out how much it costs to paint the concrete sound barriers or extract and filter the air coming from tunnels for example, you’d come to a big hairy number. Let alone if you then worked out the social and environmental costs of not doing anything about the pollution, heat, and social costs.
Australia’s massive investment in infrastructure provides a unique opportunity to rethink things and make our infrastructure work smarter and cleaner than ever before.
It’s time to raise the challenge to the key designers and visionaries behind our infrastructure projects. With a collaboration of the brightest minds in the key fields, we could come up with a way to re-think our infrastructure and to make our new infrastructure projects vibrant, living things for the benefit our community as a whole, and something that can put Australia at the forefront of wise investment. What’s stopping us apart from a bit of collaboration and some inspired thinking?