Why aren’t more cities building with nature?

Nature-based solutions (NbS) play a vital role in reducing flood and drought risks, heat stress, and pollution across cities. Yet many city planners continue to rely on grey infrastructure instead. What’s stopping them from working with nature to tackle the challenges facing cities today?

When floods and landslides struck the village of Nog, nature came to the rescue

In the summer of 2023, North India saw heavy rainfall, with up to 42cm of precipitation over Rishikesh. As flood protections burst and roads flooded, the region faced significant loss of life and damage to its infrastructure.

One village, Nog in the Bilaspur district, was remarkably unaffected by the flooding. The secret to its resilience? Soil bioengineering: a nature-based technique that improved rainfall infiltration around the village and continues to protect its roads from landslides and other major disruptive events.

Nature-based solutions (NbS) like those used in Nog can significantly reduce the risks of landslides and flooding and curb heat stress and pollution. And if they can have this sort of positive impact in a village, how much good can NbS achieve in a city with a much larger population?

The benefits of nature-based solutions in urban environments

In the case of Nog, NbS helped preserve critical infrastructure and save lives. Not every region will see such a life-changing result by implementing NbS, but building with nature can still help solve many of the key challenges facing cities today. By using NbS, cities can:

• Mitigate urban flooding with permeable infrastructure that can better absorb and redirect water 
• Address water quality issues in cities by combining natural filtration solutions with traditional water treatment plants
• Control emissions while reducing heat by planting leafy trees and moss or using vegetation
• Improve urban flood resilience and stormwater management by implementing NbS around rivers and in coastal areas
• Offer more green-blue spaces to enjoy, improving citizen well-being, biodiversity, and public health

When designed well and implemented in smart ways, NbS can help cities solve their challenges around pollution, biodiversity, and public health – issues that are all becoming more urgent as urban populations expand and the climate continues to change at a rapid pace.

These issues are particularly pronounced in regions already impacted by the effects of climate change. Across the Asia-Pacific region (APAC), for instance, cities face a tremendous physical threat as rising populations clash with storms, cyclones, flooding, landslides, heatwaves, and even land loss as parts of these cities become submerged.

In fact, some parts of Jakarta sink by up to 25 cm each year due to continued urban development and groundwater extraction – leading to 40 percent of the city now lying below sea level.

While traditional grey infrastructure can help alleviate some of these challenges, the impermeable materials used can contribute to additional heat stress and flooding. Bringing in NbS is the way to help tackle many of these pressing issues in cities.

If NbS can have such positive impacts, why isn’t every city deploying them?

While many cities are embracing NbS, others still rely heavily on grey infrastructure. A recent report from the European Environment Agency found that 91 percent of local climate action plans across the continent already include NbS.

However, at the individual city level, the picture is very different. In some regions of Europe, green coverage of public spaces can vary from 7 percent to as much as 96 percent.

The question for those continuing to rely on grey infrastructure is: “What’s stopping us from building with nature to tackle some of their most pressing challenges?”

Beyond the usual obstacles of securing funding, engaging stakeholders, and identifying and implementing the most appropriate solutions, urban environments introduce several unique blockers to deploying NbS. Municipalities must find ways to address these obstacles if they want to make the most of NbS. Below, we’ll discuss three unique blockers that are common in urban environments.