Urban Evolution: Engineering the Eco-friendly Cities of Tomorrow

As we grow as an urban society, the pressure on resources, infrastructure and the environment become intense. The more people there are, the more we need, right? That’s no problem, the true issue lies on how we meet this demand for more. That’s where engineers come into play. They are the ones who are developing sustainable solutions to contribute to urban growth while balancing our planet’s health. Creating cities that are not only liveable but will last for centuries to come. Let’s have a look at some innovative ways engineers are creating smarter cities! 

Vertical Farming

Did you know 44% of our world’s habitable land is used for agriculture? That is about 5 times the size of the United States! Many countries are already going through a housing crisis, and most of our land that could be used for putting roofs on peoples’ heads are instead used for corn. Except not any more! Vertical farming is a promising solution to this land usage situation. Vertical farming is a method of producing crops in stacked layers in a controlled environment. They’re usually found in urban areas like greenhouses, warehouses and other buildings as a way to incorporate greenery into the city. Vertical farming has many benefits such as using 90-95% less water, and 98% less land. It also protects the fertility of soil and reduces the need for transportation. The global vertical farming market is expected to reach $33 billion USD by 2030. This just goes to show that the future is vertical! 

Sponge Cities

Climate change is not news for anyone. It’s something that’s so widely talked about yet so little is done about it. Many challenges start to uncover like rising sea levels, floods and extreme weather conditions. Engineers are at the forefront of designing cities that adapt with these new realities. One key example is ‘Sponge Cities’. These are urban areas where there's an increase of natural areas like trees, lakes and parks that absorb rainwater. This is important because many urban areas are undergoing extreme heavy rainfall that causes floods and results in the destruction of livelihoods. In the United States after sponge city strategies were implemented, peak flow run-off was reduced by 81%. Rain gardens and parks can reduce the pressure put on our stormwater drainage systems by absorbing it into the ground. Now people in the city can live their lives without the worry of a single flood taking it all away. 

Green Rooftops

Imagine turning the roofs of skyscrapers into mini gardens that keep buildings cooler and the air fresher, that is the magic of green rooftops! Green rooftops are the perfect solution for turning unused urban spaces into an eco-friendly haven. They’re made up of special individual layers from waterproofing membrane, growing medium, a drainage layer to vegetation growing on top. Green roofs provide improved air quality by capturing airborne pollutants through plants. Some of the hottest surfaces in urban areas are black rooftops, so by covering them with vegetation, light gets absorbed instead of being turned into heat energy. They also help reduce the distribution of dust throughout the city and the production of smog, this plays a role in reducing greenhouse gas emissions. But that’s not all, they also help with stormwater management, in the summer they retain 70-90% of precipitation and 25-40% during the winter. The vegetation on green roofs store rainwater, and it gets released back into the atmosphere through evaporation. With how useful green roofs are, many cities are making it mandatory for there to be green roofs on all skyscrapers! 

Self Healing Concrete

Say goodbye to crumbling concrete thanks to this breakthrough material that springs into action when cracks appear! Self-healing concrete is smart concrete that repairs internal cracks itself. There are two types of this concrete, called autogenous and autonomous. The autogenous concrete reacts when water enters a crack and triggers the healing process. More specifically, the cracks are filled with calcium carbonate that is formed from the calcium in the hydrated cement and carbon dioxide dissolved in the water. Autonomous concrete incorporates chemical repair agents, biological bacteria and induced healing materials into ordinary concrete. But what does this mean in terms of our environment? Cement manufacturing and production contributes to a large amount of greenhouse gases in our atmosphere. So by making our infrastructure more durable and long-lasting, self-healing concrete reduces the energy and resources spent on repairs. Meaning we won’t have to continue producing more cement to fix damages.

Conclusion 

Urban evolution is in full swing and engineers are the ones leading this change for smarter, cleaner, and greener cities. From farming up, to self-healing concrete, this proves that living in bustling cities does not have to come at the expense of our planet that has been around for years. With ideas like sponge cities and green rooftops, sustainability isn’t just a word, it's the change for the cities of tomorrow!  

References

Behm, S. (2024, May). Vertical farming is growing up | FCC. Farm Credit Canada. Retrieved November 3, 2024, from https://www.fcc-fac.ca/en/knowledge/vertical-farming-is-growing-up

Concrete Pipe Association of Australasia. (2010, May). Autogenous Healing. Humes NZ. Retrieved November 16, 2024, from https://www.humes.co.nz/assets/Product-Guide/2a19596297/Autogenoushealinginconcretepipe.pdf

Green Roofs for Healthy Cities. (2022, November). About Green Roofs — Green Roofs for Healthy Cities. Green Roofs for Healthy Cities. Retrieved November 7, 2024, from https://greenroofs.org/about-green-roofs

GSA. (2021, June 4). Green Roofs. GSA. Retrieved November 7, 2024, from https://www.gsa.gov/governmentwide-initiatives/federal-highperformance-green-buildings/resource-library/integrative-strategies/green-roofs

Harrisberg, K. (2022, April 11). What are 'sponge cities' and how can they prevent floods? Climate Champions. Retrieved November 5, 2024, from https://climatechampions.unfccc.int/what-are-sponge-cities-and-how-can-they-prevent-floods/

Ritchie, H., & Roser, M. (2024, February). Half of the world's habitable land is used for agriculture. Our World in Data. Retrieved November 3, 2024, from https://ourworldindata.org/global-land-for-agriculture

Szujo, J. (2023, November 9). Sponge Cities. Climatlantic. Retrieved November 5, 2024, from https://climatlantic.ca/blog/sponge-cities/