Urban Sprawl: What It Is, Why It Happens, and How It’s Impacting the Natural World

When we’re running from household duties to work, trying to make the most of our time amid social, political, and environmental challenges, it’s easy to forget that the Earth is a vast ecosystem that relies on balance.

But humans are decidedly unbalanced, and the way we occupy and own space constantly shifts the world’s delicate equilibrium. One of the biggest contributors to this evolving ecosystem is the fact that human populations are increasingly building urban city centers outward, using up land and resources in the process.

In the past century, urban sprawl has increased dramatically, and its impact on how humans live and work is only matched by its profound effect on the environment. Let’s take a closer look.

What Is Urban Sprawl?

EBSCO defines urban sprawl best: It “refers to the unplanned and uncontrolled expansion of urban areas, often leading to a mix of incompatible land uses and inefficient urban service provision.” ⁽¹⁾

The uncontrollability of urban sprawl — also known as land take — is key here: Without careful, sustainable planning, unmitigated sprawl often ends up exacerbating the social and economic problems it sets out to solve.

Several factors contribute to urban sprawl:

Construction that outpaces population growth, largely for economic gain
More and different job opportunities in urban areas, compared to rural areas
A lack of investment and resources put into rural areas
The need to get out of overly dense urban spaces, thereby expanding cities and towns outward

The combination of these factors lead to ever-growing urban centers, which end up taking land and resources from the more rural areas surrounding them.

Urban Spaces: Taking Over the World

A report from the Joint Research Centre found that 45% of the world’s population lives in cities in 2025. In 1950, that percentage was only 20%. ⁽²⁾ In fact, since 1975, constructed areas have expanded at double the rate of the world’s population, meaning cities are growing faster than humans are.

Between 1990 and 2014, worldwide urban sprawl increased by 95%, as urban areas grew by nearly 28 kilometers squared (km²) per day, reports one foundational study. ⁽³⁾ Of all global areas, Europe has sprawled most rapidly, with constructed areas growing 51% since 1990. Land take in Europe between 2012 and 2018 alone increased by 3,581 km².

At the same time, the United Nations’ World Urbanization Prospects 2025 showed that while many city populations around the world are growing, more than 3,000 experienced population declines within the last decade. ⁽⁴⁾ In some cases, construction grew even while the number of residents shrank.

What does this collective data reveal? It underscores that urban areas are expanding uncontrollably, often in response to misconstrued human needs. As such, the Joint Research Centre projects that two-thirds of the global population growth by 2050 will occur within cities, with core nations adding more than 500 million residents to their areas. ⁽⁵⁾

Infographic design by Boris Benko

What Urban Sprawl Means for the Environment

Rapid urban expansion changes the way people live their lives. Decentralized urban areas mean decreased access to public transportation, greater car commuting, and increased use of natural resources like water and air.

As human activity shifts, so, too, do the habitats and microclimates that sustain us. Unmitigated urban sprawl, the research shows, can have devastating effects on the environment, including:

Increased soil sealing. Between 2012 and 2018, urban sprawl in Europe caused soil sealing — or the coverage of soil with impermeable human-made materials — increased by about 1,467 km². ⁽⁶⁾ This expansion destroyed a significant amount of croplands and added 4.2 million tonnes of carbon to the atmosphere.
Destruction of wildlife habitats. According to the European Environment Agency, land take causes natural habitats to fragment, resulting in habitats in urban areas to be four times smaller than in rural areas. ⁽⁷⁾
Greenhouse gas emissions. Daily living in urban areas causes a dangerous increase in greenhouse gas emissions, as smaller, more compact cities tend to have better transportation systems. The more cities spread, the more people have to rely on cars to get around. ⁽⁸⁾ But it’s the construction of urban sprawl that really takes a toll. The European Environment Agency found that building construction accounts for 39% of global greenhouse gas emissions. ⁽⁹⁾
Reduced air quality. Bigger city areas often result in more pollution, bringing harmful contaminants into the air. The European Environment Agency found that only 13 European cities had good air quality in 2022 and 2023. ⁽¹⁰⁾

Growing Sustainably Into the Future

The impacts of urban expansion on the environment are undoubtedly great — and grave. But there are fortunately ways to meet the needs of human populations without damaging the environment, and many European initiatives are underway to promote those actions.

The EU Soil Strategy for 2030 has set soil sealing and urban sprawl targets in order to reach land take neutrality by 2050. ⁽¹¹⁾ Similarly, the Urban Agenda for the EU is a multi-entity organization geared toward sustainable urban planning and sprawl mitigation. ⁽¹²⁾

These initiatives are combining the best of humanity — creativity, responsibility, and adaptability — with growing human needs. Urban expansion will no doubt continue, but with organizations like these at the forefront, humans can make the most of their cities while protecting the natural world around them.