Rewilding, which consists of “conservation efforts aimed at restoring and protecting natural processes and wilderness areas,” is usually done away from cities, in more rural areas and involves, to simplify greatly, letting land go back to its natural state. The word still seems fitting though, for the two short articles below, where man-made structures are replaced with hybrid ones, bringing more nature back into, and around cities.

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Paris’ Promenade Plantée and New York’s High Line are just two of the most famous examples of transforming elevated structures. Nick Dunn explains some of the reasons why turning old city bridges into new urban parks is such a great idea.

Aqueducts, viaducts, and elevated train tracks have been turned into popular linear parks like the ones above, but as with many urban upgrades, have also brought rising prices and gentrification.

Recent research has shown that without policies in place to ensure that lower-income local communities can enjoy the benefits of newly greened spaces, including health benefits, these projects can actually exacerbate inequality by raising property values and causing the displacement of long-term residents who can’t afford to stay. Urban planning experts talk about green gentrification, as has been noted in the case of the 606 linear park in Chicago, among others.

Those projects can be regrouped, along with bridges or ground level railways, under the term “urban acupuncture,” creating “pocket parks out of small, hidden or overlooked bits of land between existing buildings.” And although, as stated above, policies must be enacted to control gentrification, these structures have the advantage of often being situated in post-industrial parts of cities, places in need of regeneration.

Linear parks thus weave nature into the flow of a city. They support wildlife. They encourage sustainable transport and physical activity (walking, biking, jogging).

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Climate change brings rising waters, rising tides, and more numerous and stronger storms. Seawalls are often seen as a solution, but bring their own list of disadvantages, like intensified surges at neighbouring beaches and destroying nearby ecosystems. “As a result, rather than representing a surefire way to reach flood resiliency, these structures may actually open the door to greater climate vulnerability.” So, can nature-based alternatives to seawalls keep the waves at bay?

Sea level rise is inevitable, [w]e have to allow the shoreline to adapt and be resilient rather than put up seawalls, which are obstructive.

The article provides an overview of various solutions or hypotheses where seawalls are replaced by more porous structures meant to increase biological activity where nature and the structure (like granite rocks and eco-concrete) work together. Some experiments are also being done with interlacing floating mats with growing vegetation, providing oysters with room to grow, and the restoration of mangroves, among others.

“We need to look beyond traditional civil engineering,” Hopkins said. “We’re entering into a climate era that is unknowable, and we need solutions that are flexible.”