Currently, 83 percent of the US population lives in urban areas. By 2050 that percentage will climb to 89 percent. This increase in population has consequences—as more people move to cities, more people will need housing, commercial spaces, and recreation areas. In order to keep up with this demand, cities will need to learn how to grow more sustainably, moving away from solely considering the best result for humans and toward techniques that can support humans while also stopping the destruction of biodiversity.
To address this need for sustainable design, the Terrascope Class of 2024 proposes several development goals and metrics for currently expanding cities. Based on the design of several existing cities, the Class proposes urban park creation, tree planting projects, wildlife corridors, roadside corridors, green roofs, and green walls in the land area incorporated into the expanding cities.
The guidelines are as follows:
- The city maintains a 2.6 square kilometer park near the urban center and ensures that 15% of new land becomes park space.
- Parks are evenly spaced with an average area of .08 square kilometers.
- Public trees cover 21% of new land (this may include trees in urban parks).
- A green connector spanning the diameter of the city is constructed at the rate of urban expansion.
- Any new major roadways are lined with two columns of trees.
- Public school buildings maintain a nine square meter green wall and a 37 square meter rooftop garden.
The cost of implementing these projects throughout five decades of expansion is calculated using the historic expansion rate of Las Vegas, Nevada. The resulting idealized city has been named Terratopia by the class.
The Terrascope Class of 2024 has developed a four prong conceptual model for city design that centers the health and wellbeing of both human and wildlife communities to better coexist. These four prongs can be remembered as GROW:
Open green spaces
G: Green buildings
The defining feature of urban areas is their buildings. With this solution proposal, cities are able to greenify their “concrete jungles” through mindful architecture that is inclusive of native flora and fauna. Green walls, green roofs, and lawns incorporating native vegetation are all ways for a city to provide “rest stops” for smaller arthropods, reptiles, and amphibians. These features would strengthen connectivity of green spaces, allowing for greater gene flow among wildlife and subsequently a more resilient population.
R: Reconciled Roadways
Roadways are another major obstacle in creating a space that is inviting and safe for native wildlife. To help alleviate the fragmenting effects of roads, this model includes stretches of dense tree coverage running along major roadways as well as increased tree cover across the whole city—projected 21% of the city’s total area.
O: Open green spaces
Green spaces have tangible benefits for both city inhabitants and wildlife. The solution proposal emphasizes not only maximizing the total area of open green spaces in a city, but ensuring that green spaces have connectivity between them to aid gene flow of native flora and fauna. As such, the model includes a larger central park as well as numerous smaller green spaces throughout the city.
W: Wildlife corridors
Besides smaller roadside corridors, the solution proposal includes a larger wildlife corridor that runs across the length of the city. In this corridor, native vegetation would be extremely dense. The only human activity through the corridor is a suspended walkway modeled after the West Loop Park Connector in Singapore, with roads passing underneath the corridor to cross from one side to the other.