Urban Expansion and Land Use

Summary——————–Overview——————–Solutions

Land only takes up 29% of the Earth’s surface. Of that, some areas are not habitable [hot/cold/rocky deserts], some are used for agriculture, while others are populated by vegetation, freshwater bodies, or humans.

In 2018, 55% of the world’s population lived in urban areas. This is projected to increase to 68% by 2050. A scary thought for those who live in already extremely dense cities. However, if we can expand our cities the right way, in the right direction, then we’ll all fit just fine – while increasing energy efficiency and reducing biodiversity loss.

Worldwide, urban land expansion is happening at a faster rate than urban population growth rates. This shows that as we move further away from city centers, we start building larger houses and neighborhoods instead of apartments and condos. This corroborates the idea that someone living downtown is likely taking up less room than others who live near the city limits [some studies have attempted to quantify this ‘urban sprawl’ and have found that urban area growth rate is over twice the urban population growth rate].

Agriculture and Energy Delivery

In 2019, agriculture [i.e. crop and livestock farming] occupied roughly 50% of the Earth’s habitable land area. As food production booms, this percentage is bound to increase if we continue with our unsustainable food systems. The main problem with agricultural expansion is that it directly competes with areas that are already populated [e.g. green ecosystems, cities, etc…]. And since food production is an immediate necessity, it usually takes precedence over the preservation of our environment. It’s estimated that agriculture was responsible for around 73% of tropical deforestation worldwide from 2000-2010 [with tropical deforestation accounting for roughly 95% of total deforestation].

Energy delivery is another necessity that can compete with populations for land area, as pipelines are being built across ecosystems and local communities – like the 670 km Coastal GasLink pipeline in Western Canada that sparked protests across the nation.

Unfortunately, land use conversion of our green ecosystems releases billions of tonnes of GHGs into the atmosphere every year – and induces significant biodiversity loss through habitat loss.

Human Land Space

Humans don’t take up that much space for housing and infrastructure compared to agriculture. Even with almost 8 billion people on Earth in 2021 [projected to peak at 9.73 billion by 2064], only 1% of habitable land is considered “urban and built-up”. Regardless, we need shelter to live in humane conditions. And if the global population is expected to grow by close to 2 billion people in less than 30 years, we’re going to have to expand our cities.

But we’re getting ahead of ourselves. We’re already unable to secure good living conditions for the world’s current population. In 2020, an estimated 1.6 billion people lived in inadequate housing conditions [adequate includes a minimum of the following elements: legal security of tenure, affordability, habitability, accessibility, proximity to services, availability of infrastructure, and cultural adequacy]. That was equivalent to over 20% of the global population at the time.

In addition, a 2005 U.N. report established that approximately 100 million people were homeless. This has surely increased since, especially with the COVID-19 pandemic.

Combining the problems listed above with the fact that middle classes of highly populated developing countries continue to get richer, the demand for more space keeps increasing [since higher income almost always leads to more spacious housing]. The most widespread solution so far has been urban expansion.

Unfortunately, there are 2 major problems with this:

  • As cities expand, the new homes will need to be connected to the rest of the world with water and gas pipes, roads, electricity, and more. The infrastructure required to expand our cities requires loads of money, materials, and energy. The longer commutes to CBDs [central business districts –where most people work or go for leisure] would also increase GHG and toxic emissions from transportation.
  • If our cities expand, then they’re expanding into a previously occupied area. Most of the time, that ends up being forests, grasslands, or other green ecosystems. These ‘expendables’ that surround our cities will continue to be chopped down as cities grow, as they have been in the past. Urban expansion caused roughly 10% of tropical deforestation from 2000-2010.
Slowing Urban Expansion

To avoid spreading into green ecosystems and depleting resources, we’ll need to adopt more efficient housing strategies. We’ve got some examples in the solutions, but we’ll go over the most important large-scale solutions here.

As a no-brainer, we’ll need to discourage people from owning [and not renting] multiple homes. Especially those located in urban areas – remote cottages are a bit different. To do so, we’ll have to change the current notion that wasting valuable land [i.e. owning secondary urban homes] is a sign of success. In truth, it’s extremely concerning that individuals are allowed to play Monopoly while homeless people roam the streets. Stronger policies and regulations can help dissuade anyone from owning more than one home in urban areas.

On top of that, owning a vacant second home roughly doubles our land use footprint, which has consequences in urban areas. Since these homes are off the market, a trickle-down effect [e.g. wealthy individuals can’t buy a home in the city center, so they might settle for a home near the city’s periphery, and so on] eventually forces less fortunate individuals to move away from the city center to find an affordable home – contributing to urban expansion.

In the same boat as making sure all homes are occupied, we have its square footage. Evidently, if a large house is built on twice the area of a standard house, then from a pure land use perspective – the effects are essentially the same as owning a second house. This is why apartment buildings are fantastic as far as land use efficiency. Building higher, as opposed to larger, means our individual land use footprint would be incredibly small.

For example, imagine a tall apartment building that can accommodate over 200 families, while only occupying the land area of 4 standard houses. In this scenario, each apartment ends up occupying just 2% of the area of 1 standard house. That’s a lot less than the 200-house alternative. And to compensate for the lack of backyards, we could easily have large green areas like parks and gardens nearby. All we have to do is expand higher instead of spreading.

More urban green areas would also be extremely helpful for air/noise pollution control and water management. Vegetation and soil can absorb pollutants and reduce precipitation runoff during storms to help large cities save hundreds of millions of USD every year. The more green spaces there are, the more a city can save.

Additionally, if we lived closer to one another in apartment buildings, we’d be reducing the amount of resources we consume in our day-to-day lives. Examples feature lower gasoline consumption due to smaller commutes [and increased public transit use], less pressurization required for natural gas and water transport, and less electricity losses. Without forgetting the enormous quantities of metal, asphalt, and concrete we can save by not extending roads, water mains, gas pipes, and electricity transmission networks. We’ll also be able to share more, which will reduce our material consumption. For example, apartment buildings can have shared laundry machines, game consoles, pools, and even cars [e.g. with a simple online booking system].

Conclusion

Decreasing our individual living area is necessary, as ecosystems around the world are suffering from land use conversion. As our population and individual demands grow, we will be faced with a choice. We can keep expanding into our environment and depleting natural resources while losing energy efficiency, or we can show restraint and change our way of thinking about housing. Building higher will lead us to lower individual land use and carbon footprints. It will also free up more space for nature to grow in urban areas, allowing more sustainable agriculture to take place locally. All the while avoiding further land use conversion. Everyone stands to benefit from more green spaces in urban areas, even city budgets.