Unbuilt Environments

We face a fork in the road.?

Today, urban areas around the world are expanding on average twice as fast than their populations. Formerly fertile and productive agricultural lands across developing countries are being converted into urban use. Experts predict a tripling of global urban land between 2000 and 2030. And although urban land covers a small fraction of the earth’s surface, cities trigger global environmental change, driving habitat and biodiversity loss and the depletion of carbon stored in vegetation, oceans and soils. The encroachment into nature also make our settlements less resilient by disrupting the natural systems that protect our communities. One only needs to see how the urbanization of the upland areas of Metro Manila have contributed to perennial flooding in downstream localities. Negative effects of urban expansion such as these including that of traffic congestion, health and disaster risk and inequitable access to space have reached a new level of awareness, challenging planners, developers and policy makers who shape our built environment.

?Urban Green Infrastructure

The role of government, both at local and national level, is to be the lead agent in the shaping of urban space recognizing its impact on economic growth, social equity, and environmental protection. Infrastructure and land use decisions today will lock in food, water, material, and energy flows in the future. Urban policies can either entrench unsustainable and inequitable development practices or correct them.?The good news is there is still an opportunity to alter our course.?According to the United Nations, 40% of the material urbanization of 2050 still needs to be built.?This presents a tremendous opportunity to shift from the business-as-usual, resource-intensive mode of property development towards one that is restorative.?Ironically, some of the best infrastructure systems we may conceive of may be the ones that we choose to un-build, or at least build differently by emulating nature’s processes. We could learn perhaps form some examples that are already being pursued in many cities around the world.

?Design Nature In

In cities where land is scarce, urban afforestation is achievable using the Miyawaki method which densely plants shrubs and trees on small plots of land, turning them into tiny forests. By planting 2 to 4 different tree species per square meter, Miyawaki forests grow faster and mature to become carbon sinks that reduce urban heat island, attract birds and insects, regenerate the soil, mimicking the complex adaptive ecosystems of forests in urban areas.

?In some European countries, rewilding has been adopted as a strategy to diversify jobs and investments while restoring habitats and natural processes in rural areas and coastlines.?They attract new forms of tourism that encourage co-existence and co-creation.

?In New York’s Staten Island, the Landscape Architect Kate Orff developed “oystertecture” as a way of using nature to cleanse the shoreline, mitigate storm surge and form a new waterfront civic activity by rebuilding oyster habitats along the coastline for wave attenuation.

Daylighting Streams

Conventional engineering practices for storm water management is unidirectional, linear and focuses on conveyance—putting rainwater in pipes and disposed far away as quickly as possible.?As urban areas are developed, waterways are often redirected, buried in pipes to create a more buildable surface area or in an attempt to protect properties from flooding. Unfortunately, burying or covering waterways has the unintended consequences of increasing nutrient pollution, degrading habitats, and increasing downstream flooding by increasing the rate of flow. And since pipes have a limited capacity and cannot anticipate severe storm events, their inlets can create choke points during high volume flows, creating localized flooding.

Daylighting reestablishes rivers and streams to their original channels.?Many places have started to do this, bringing formerly buried streams to back to the surface?to reduce peak flows and increase flow duration. In so doing, bio-habitats are restored and surrounding communities amenitized.

utting a Lid on Grey Infrastructure

In places where Grey Infrastructure such as roads, parking lots, pipes, dikes cannot be replaced with green infrastructure, putting a physical lid on them helps create additional space for civic uses and greenery, restoring nature and communities. This approach has been used and is being considered on several highway projects in the US, often initiated by citizens and local neighborhoods.

One of the more popular of such lidded projects is Millennium Park in Chicago. Now an iconic landmark and a major tourist attraction for the US mid-west, it was built over a parking lot and a rail yard, making it one of the largest green roofs in the world.

?More drastically, last year the US passed a bill that aims to spend $1 Billion to remove freeways that have carved through neighborhoods. That’s right, an infrastructure plan that proposes to remove roads, not build them— to undo the environmental and social damage produced by highways.

?These are all examples of solutions that integrate land and marine use plans, shaped by local communities and nature-based enterprise zones, incentivized through public funding, and enabled by private capital investment.?They change the status quo by changing the way we think about infrastructure.?

?The planning of cities is more a political act rather than a technocratic exercise.?There is a need refocus political agendas to recognize the urban reality of our time and mitigate the imminent crises of our future. My years working in a big corporation has taught me that strategy is not just about choosing what to do, but also about choosing what not to. If buildings contribute significantly to carbon emissions and environmental degradation, then there is prudence in restraint and selectivity. The challenge is to channel our collective creativity towards what’s essential in improving the human condition. The purposefully unbuilt, to avoid harming our fragile urban, societal, and natural systems, have value in their absence.

?The fork in the road is about choosing to build better, not just more.

Original article published in the Philippine Daily Inquirer, March 5, 2022?

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Bishan-Ang Mo Kio Park, Singapore. A former concrete channel, renatured. Photos: Dreiseitl /Ramboll

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Then and now. Millennium Park, Chicago. Putting a green lid on grey infrastructure

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Putting a lid on the I-5 in downtown Seattle. Photo: lid15.org