Top 5 Ways to Green Our Cities
In cities, nature-based solutions can be applied as green infrastructure, providing a wide range of multiple co-benefits. Read about the top 5 ways to green our cities.
In the urban context, nature-based solutions (NBS) can be applied as green infrastructure (GI), which is a strategically planned network of natural and semi-natural areas that are designed and managed to deliver a wide range of environmental, economic, and social benefits.
GI varies in the scale and scope and includes the levels of buildings, public spaces, water bodies and drainage systems, and green corridors. GI provides three main opportunities:
- GI supports economic development in urban areas, which is dependent on the amount and quality of natural resources available, including water for sanitation and manufacturing.
- Urban planning that incorporates GI has a positive environmental impact, such as mitigating emissions through increased carbon storage and increased resilience to floods, droughts, and heatwaves.
- GI contributes to the social dimension of urbanisation, such as green space increasing people’s perceived happiness and general health. Overall, by working with nature, cities can deliver a wide range of ecosystem services to residents.
1. Green roofs
A green roof is a space on the top of a building that is covered partially or entirely with vegetation that is planted in a growing substrate. However, while ‘green’ refers to vegetation, not all green roofs are uniformly green in colour, with different vegetation types or features, such as sandy soil and stones, added to create wildlife habitat, resulting in a variety of colours and textures. Green roofs can be used to reduce the impact of high temperatures, collect stormwater, reduce pollution and fine dust, reduce energy costs in heating and cooling buildings, and act as carbon sinks, all the while enhancing biodiversity.
2. Urban rooftop farming
Urban rooftop farms are spaces/areas located on building’s rooftops, used for growing vegetables, fruits, and nuts using raised beds, row farming, or hydroponic greenhouses. Urban rooftop farming provides a wide range of benefits including increased social interaction with neighbours and the wider community, increased property values, improved food security, stormwater retention, improved air quality, and carbon sequestration.
3. Rainwater harvesting
Rainwater harvesting systems collect and store rainfall for later use. Passive harvesting systems, for example, rain barrels, are typically small volume systems designed to capture rooftop runoff. Active harvesting systems, for example, cisterns, are larger volume systems which capture runoff from roofs or other suitable surfaces. Rainwater collected in active systems is typically used for irrigation or for indoor non-potable water replacement, for example, toilet flushing, clothes washing, evaporative cooling, etc.
4. Green facades and walls
Green facades use pot bound plants to create positive effects on the surrounding indoor and outdoor climates. A green wall is comprised of plants grown in a supported vertical structure attached to an internal or external wall or left freestanding. Green facades and walls can improve air quality by capturing fine particulate matter and reducing carbon dioxide levels, reduce the urban heat island effect, lower energy consumption of the building, and create habitats to conserve and preserve biodiversity.
5. Urban parks
Typically, parks contain open spaces that absorb stormwater and offer water quality, habitat, and aesthetic benefits. Park infrastructure, including carparks, roads, buildings, playing fields, courts, and other man-made surfaces, can be built or retrofitted with GI to treat stormwater or drain it to enhanced pervious surfaces. Park infrastructure that incorporates GI provides a range of benefits including enhanced educational opportunities, enhanced social and environmental equity, and reduced maintenance costs.
The take-out
Green infrastructure comes in many shapes and sizes, providing multiple benefits to both humans and nature.
Join the conversation on the following LinkedIn groups: Urban Water Security, Our Future Water, Circular Water Economy, Blue and Green, and Nature-Based Solutions
