EDITOR’S NOTE: The following is an excerpt of “Soft City: Building Density for Everyday Life,” by David Sim, published by Island Press. In it, the author makes a case for a human-scale “soft city” that prioritizes the organization and layout of the built environment for more fluid movement and comfort, a diversity of building types and thoughtful design to ensure a sustainable urban environment and society. In this excerpt, Sim illuminates how outdoor space can enhance the experience of a city’s geography and climate, invite the community into the public sphere and mitigate the effects of climate change.

As more and more people live in densifying built environments, the importance of spending time outdoor encountering natural phenomena and learning to live closer to the seasonal cycles of the weather increases. The everyday experience of being connected to nature is a key factor in long-term health and well-being. Spending time outdoors also presents opportunities to meet other people and have shared encounters.

Everyone does not necessarily need to have their own garden, but they should have access to a range of outdoor spaces and experiences, from a window box to a roof terrace, from a balcony to a public park, from a sidewalk café to a tree-lined boulevard. These spaces can bring them closer to nature and help them live better with the weather.

Bringing Nature into the City

Biophilia is the affinity humans have to connect with nature. There are also many health benefits that come with encounters with nature. International research has demonstrated the healing benefits of seeing trees for hospital patients, and the Japanese practice of forest bathing is becoming well-known. There may not always be natural landscape close by to connect with, so the experience of nature, or at least strong elements of nature, may need to be brought into the city. There are many ways to bring greenery and water back into the urban environment. Although vegetation is probably the most important aspect of nature in improving the environment of urban places, the presence of water may be the most special. The strongest sensory experiences are associated with water, in particular running water, with sound, movement and reflection.

In Freiburg, Germany, small, shallow streams called Bächle run through the streets of the medieval old town. (Photo by David Sim)

In Freiburg, small and shallow channels of water run through the streets of the medieval core, reinterpreting a historical system of small streams. These Bächle are 20-50 centimeters (8-20 inches) wide and 5-10 centimeters (2-4 inches) deep. The water channels have multiple functions: cooling and cleaning, acting as a separator between pedestrians and trams, or defining a zone for sitting and staying. They reflect a dancing light in the narrower, dark streets. Perhaps best of all, they turn the streets into a giant playground, offering children of all ages temptation and opportunities to sail small boats, paddle and splash about. This very small feature has significantly larger consequences, allowing the streets to do more by increasing the intensity of use. The Bächle help achieve the balance between recreation (staying, sitting and playing) and function (multi-modal traffic corridors).

How Street Trees Transform Urban Spaces

Planting street trees is one of the most significant things that can be done to improve an urban environment. Beyond their inherent beauty, street trees do many useful things that help improve the look, feel and performance of urban spaces. Trees change the climate of streets (and whole cities) by providing buildings and street surfaces with shade from the sun and protection from the wind. This makes it more pleasant to spend time outdoors on the sidewalk and easier to move about on foot and bicycle or wait for transit. In this way, trees have an important role in supporting active mobility.

More than a mere green surface, trees help reduce the heat-island effect, which blights many urban places, through shading, reflectance, evaporative cooling and evapotranspiration. Trees act as privacy screens in densely built areas. They filter strong sunlight, reducing glare and can act as light reflectors, throwing a dynamic “dancing” light into buildings. Trees provide a hugely significant sensory experience for people in streets with their sounds, smells and movements. Their ever-changing appearance gives people an awareness of the seasons and the passing of time, and effectively turn streets into linear parks.

Trees absorb carbon dioxide. Since cities produce most of the carbon dioxide, it makes sense to place trees at the source of the problem and where people are most vulnerable. Trees are natural air filters, capturing dust and other particles from the air by trapping them on their leaves and in their bark, as well as absorbing unpleasant smells and pollutant gases such as ammonia, sulphur and nitrogen oxides. This is particularly significant in relation to vehicle emissions.

In Havana, street trees form a canopy that creates an outdoor room and softens the climate for walking and lingering. (Photo by Lars Gemzøe)

Connecting to the Nature That is There

Almost every town or city has some natural amenity, whether it’s some kind of water, topography or views. The way a place connects to its natural amenities and works to accentuate the best features, however modest, can have a significant effect on how much time people spend outdoors. Supports can be put in place to encourage people to spend time outside and encounter nature, and can also extend their comfort zone, making the experience feel easy, desirable and pleasurable. This could include orienting new buildings to allow views of nature, uncovering a natural stream or river, planting street trees allowing microhabitats to bloom or simply placing furniture outside of a café, allowing people to sit in the sun.