Greening Sydney Strategy
Welcome
These interactive maps and diagrams support the public exhibition of the City’s draft Greening Sydney Strategy.
Explore them to better understand the benefits of greening, how we measure and track greening over time, and where we need to be by 2050
Download an activity book for your school or community group.
How we measure and collect data
Greening data is usually measured from the air using a special camera mounted to a plane.
This story map contains canopy cover, heat and other data acquired by the City of Sydney and other sources over the past 12 years. During that time, like many other technologies, data acquisition and analysis has improved. We will continue to refine our technologies and processes over time.
Explore
What greening and canopy means
Greening is all the vegetation measured including turf, trees, and rooftop vegetation. Tree canopy is any greening greater than 3m above ground.
Hyde Park North has 89% green cover and 54% tree canopy cover.
Ultimo has 18% green cover and 15% tree canopy cover.
Different types of greening
After the raw data has been captured, we group the information into specific height ranges. This helps us classify what is ‘canopy cover’ and what is ‘greening’.
Any vegetation above 3 metres is classified as ‘canopy cover.’ Everything below this height is classified as ‘greening’.
Turf or planting located under a tree’s canopy is not counted towards the overall greening count.
Activities:
- Explore the map to find where the most rooftop gardens are in the city.
- Can you find the areas with the most red on the map? Why do you think these areas have more red than others?
Canopy and greening in your area
Do you have enough tree canopy in your local area to help improve your physical and mental health, and protect you from the next heatwave?
See how green your neighbourhood is.
Activity:
- Find your school or home on the map.
- What is the percentage of canopy cover and greening?
- Is it more or less than the city’s current percentages of 18% canopy cover and 32% greening?
- What are some things you could do to increase greening in your local area?
Changes over time
Our greening and canopy is always changing
As our city develops over time, our urban forest is impacted by a range of factors that influence the amount of canopy cover within individual properties, streets and parks, and collectively over precincts and the entire city
The City of Sydney is one of a few local governments in Australia that has consistently increased canopy cover over time.
Activity:
Find a photo from the City’s online archives collection of a street or park in your local area. Compare them to modern photos. When was the photo taken? What differences can you see? Is your area greener today than it was in the photo?
Why greening and canopies change over time
Canopy changes occur as a result of major urban renewal and infill development, infrastructure and upgrade projects, and the removal and replacement of individual trees as part of natural processes.
It takes time for a canopy tree to establish. Their removal in contrast, is quick and results in an immediate loss of the canopy cover and benefits provided. It can take many years to re-establish that canopy cover.
Understanding the impacts of these changes, and the time frames over which they occur, is important in managing a city’s urban forest, and the role everyone has to play in providing their share of canopy and greening.
2008 vs 2019 canopy coverage
The left map illustrates what the City of Sydney's canopy coverage looked like in 2008 while the map to the right illustrates the 2019 canopy coverage.
Each point on the maps represent an area. In this case each area is a circle. Each circle has a radius of 100m. The colours represent how much canopy falls within that circle area. Dark green represents a lot of canopy cover while red represents a small amount of canopy cover.
Scroll through the application bookmarks to visit areas of considerable change.
Activity:
Find your school or street on the map. Has canopy cover increased, decreased or stayed the same between 2008 and 2019?
The benefits of urban greening
The benefits of urban greening
⦿ Cooler roofs as a result of green roofs increase photovoltaic collector efficiency
⦿ Green roofs extend the opportunity for habitat, increase building insulation, store and slow rainfall runoff and drastically reduce urban heat build-up during the day and night
⦿ People tend to shop, dine and linger longer in attractive green environments improving commercial returns
⦿ Permeable pavements and raingardens slow and collect rainwater that can then support urban greening and remove pollutants
⦿ Vine covered shade structures and green facades provide shade to buildings, reduce urban heat, increase visual appeal and privacy. They can also be used where spaces don't allow tree planting
⦿ Views of trees and lower level greenery increases the value of residential and commercial property
⦿ Shading of road and other pavements increases their longevity and drastically reduces ambient heat build-up and radiation at night
⦿ Shade provided by trees helps reduce air conditioning costs
⦿ Trees and other greenery increase habitat, shelter and food for animals
⦿ Trees provide shade that reduces overall urban heat, improves the walkability of streets and reduces incidences of skin cancer. Use of deciduous trees can also allow winter sun and thereby reduce heating costs in winter and facilitate use of parks in cooler months
⦿ Canopy coverage of at least 30% reduces mental health issues and leads to better perceptions of overall health. It also reduces employee sick leave, improves employee and student concentration
⦿ Leaves and foliage provide shade, filter and absorb pollutants and capture and slow rainfall. They also release scents and aromas that can create a positive emotional response
⦿ Leaves and timber from pruned and removed trees can be recycled as mulch to improve soil, nutrients and water holding of soils
⦿ Tree and vegetation roots retain soil, preventing erosion and absorb water
⦿ Quality green spaces and tree canopy cover create a greater sense of community and increase opportunities for physical activity, socialisation and connections to nature. They generally improve mood and restore our minds from stress and fatigue
⦿ Irrigated lawns and gardens reduce urban heat and increase infiltration of rainwater
⦿ Trees and greenery and other permeable pavements help decrease stormwater runoff and recharge groundwater supplies and provide passive irrigation to make more resilient and longer-lived trees
Health and heat
Greening for health
Tree canopy cover is important for our physical and mental health.
Research has found that urban communities with a healthy amount of tree cover – not just grass and green space – were psychologically healthier than those that didn’t.
In neighbourhoods with a tree canopy of 30% or more, adults had lower odds of developing:
- psychological distress by 31%
- diabetes by 31%
- cardiovascular disease by 21%
- cardio hypertension by 21%
- rating their general health as fair or poor over six years by 33%
(2019 Prof Astell-Burt and Dr Feng)
Activity:
Can you name 3 benefits of urban greening?
Greening for heat
Cities create their own microclimates by influencing the surrounding atmosphere and interacting with climate processes.
Urban temperature extremes can present us with life or death situations. When temperatures exceed 25°C there is a reported increase in mortality and strokes.
To reduce the impact of urban heat, research confirms we need tree canopy at both the local and precinct scale - ideally with a minimum of 30% canopy cover.
The thermal sliders below illustrate the impact canopy has on heat.
St Johns Road, Glebe, 25 January 2019. Around 20% canopy coverage.
Westmoreland Street Glebe, 25 January 2019. Around 35% canopy coverage.
Activity:
- Compare the two streets above.
- Looking at the colours in the thermal sliders and the temperature gauge on the left, can you estimate the average temperature on each street?
- What is the difference in canopy cover for each street?
Urban heat islands
Heatwaves are Australia’s deadliest natural hazard. They now arrive earlier, are hotter, and last longer.
Urban areas create heat islands, as the built materials, such as buildings, roads, and footpaths, absorb heat during the day, and release it at night
Thermal imagery
Canopy trees help to cool surrounding hot air and surfaces, through shading and evaporative cooling. Individual trees can make a valuable difference to air temperatures at the scale of individual properties. Recent studies have shown that groups of trees that combine to provide more than 40% canopy cover at the scale of a city block can reduce local ambient air temperature by more than 1.3oC (Ziter, C. et al 2019). Limiting paved surfaces also helps to reduce heat that is absorbed and radiated into the air. Extreme heat is moderated most effectively where there is more canopy cover and less hard paved surfaces.
Activity:
This map shows that our parks and waterways are already some of the cooler places in the city. Look at the types of places that are hotter than 35 degrees. What can you identify about them?
Targets
Future ambitions
Our target is to increase overall green cover to 40% across our area, including a minimum of 27% tree canopy by 2050.
As our city continues to change and we head towards 2050, we have set ambitious targets to increase greening and canopy cover. The targets are presented as a summary of each property type or land use, and will help us monitor changes and progress over time.
Since these overall targets are a summary they cannot be applied to any individual street, park or property. We will need to explore the potential and opportunity for greening and canopy cover on each individual site to achieve the overall targets.
Meeting our targets
Streets, parks and private property all play a crucial role in greening our city. To meet our targets, we need to work together to deliver across all these areas.
Streets by increasing the number and type of street gardens and inroad greenery, and planting more street trees, including a comprehensive review to ensure the largest species appropriate for the space is planted.
Parks by planting more trees to meet the individual park’s capacity for canopy trees, and through minimising hard surfaces in the parks, where appropriate to do so.
Private property through developing programs like the Green Space Factor and Greening Sydney Fund, increasing the number of green roofs, walls and façades, and ensuring every development application delivers its minimal greening target.
Meeting our targets
Importantly, each portfolio needs to deliver its share, as there is limited capacity for others to make up any difference. It is vital that all everyone works together to deliver the targets.
Activity:
What would you like your school and playground (or your local neighbourhood) to look like in 2050?
You could sketch a design, create a collage or make a presentation.
Include some of the ideas covered in this strategy.
What do you think will remain the same and what will change?
Thank you
We hope you enjoyed exploring these maps and diagrams.
If your school or group completed any activities, we’d love to see your work. Please email it to sydneyyoursay@cityofsydney.nsw.gov.au by 5pm on Monday 24 May 2021.
