Monday, 19 December 2016 09:25

Focus on: Cool Streets Blacktown

Mayor of Blacktown City, Councillor Stephen Bali at the Cool Streets tree planting event. Mayor of Blacktown City, Councillor Stephen Bali at the Cool Streets tree planting event. Credit: Blacktown City Council

Blacktown City Council’s latest award-winning project, Cool Streets, has seen it move to tackle the Urban Heat Island Effect (UHI) with street trees.

The Council is ahead of the pack on a range of sustainability issues, including water-sensitive urban design and energy efficiency, but Cool Streets is one of those simple ideas that works well in any urban landscape.

When the hot summer sun beats down on roads, footpaths and roofs, they absorb and hold the heat well past the heat of the day, increasing the average temperature.

Urban heat is an issue for all cities, but Western Sydney is particularly affected due to its unique geography and rapid rate of development.

According to recent research from the Office of Environment and Heritage, the region’s advancing greenfield development will result in between five and 10 additional hot days by 2031[1].

Urban heat doesn’t just make people uncomfortable, it can be fatal.   

Extreme heat is Australia’s major natural killer.  The undue stress on our most vulnerable individuals can trigger medical conditions such as heat stroke and cardiac arrest[2].

Extreme heat can also have a significant impact infrastructure, transport and emergency management.

Set in the centre of Western Sydney, Blacktown already experiences high temperatures during summer.  Large-scale developments that are changing farmland into medium density suburbs in the North West of the LGA are expected to have a significant impact on heat in the region[3].

Street trees are a simple and effective way to mitigate urban heat, as well as providing shade to residents and increasing street appeal. Research also shows that well-selected, well-placed street trees can reduce household energy bills[4].

Blacktown faced two challenges.  Needing to ensure any plan addressed the occasionally conflicting requirements of authorities, service providers and residents and the common community perception that all tress are messy, dangerous, difficult to maintain and ruin kerbs and guttering.

The latter was a legacy of poor tree species selection in former decades.

The Cool Streets program sought to tackle these issues through intelligent streetscape design, good species selection and greater community participation in street tree design and planting.

Blacktown engaged consultant and landscape architect Dr. Libby Gallagher to develop street tree designs that reduce both average ambient temperature and residential energy consumption.

They included passive climate control through the strategic placement of tree species including: taller trees in the West to cut hot afternoon sun; smaller trees in the east to let in morning light; and deciduous trees in areas that required more warmth in winter.

Once these designs had been developed, Blacktown City Council began the second part of the program; community engagement and implementation.

The program started with a series of community consultations in two treeless Blacktown streets.  

The consultation began by holding a weekend barbecue in each of the selected streets to start the conversation about street trees with local residents.

An initial survey confirmed Council’s anecdotal knowledge:

-          some residents have concerns about safety and leaf litter;

-          new street trees were often damaged or removed by residents;

-          formal applications to remove trees were often prompted by unfounded concerns that branches may fall; and

-          residents were typically informed about plantings in their street but not consulted.

Council officers also took the event as an opportunity to explain the benefits of street trees and why they wanted to increase tree cover in the area. Residents were shown images of a number of planting scenarios (including small trees, medium trees and large trees) and asked for feedback.

The consultation showed that after the benefits of well-selected street trees were explained, residents were keen to have trees planted in their street – with some commenting it was unfair other streets would have trees while theirs didn’t.

By combining feedback from the consultation and the research from Dr Gallagher, Blacktown City Council brought a final street scape design back to the residents to explain why it was chosen.

Once the design was approved, the residents got involved in a planting event with the Mayor of Blacktown City, Councillor Stephen Bali.

Council found that not only were residents more positive about street trees following the program, but there was less vandalism of the newly planted trees.

Residents reported a greater sense of ownership for their street trees, and some actively engaged in taking care of them through watering.

The Cool Streets Blacktown program was so successful that several other councils have applied for funding (collectively through WSROC) to extend the program to a regional level.

WSROC President Cr Stephen Bali said: “While we can all do our bit to increase green-cover and reduce urban heat, we will only be successful in cooling Western Sydney if we adopt a regional approach to building our urban canopy.

“While street trees do require maintenance and can cause difficulties in some circumstances, good species selection and considered tree placement can allow councils to avoid many of these issues.

“The need to address urban heat is recognised by the Greater Sydney Commission through its draft District Plans, as well as the NSW Office of Environment and Heritage and the Federal Government,” he said.

“There is no arguing that Western Sydney is already much hotter than the rest of our city and we should be doing all that we can to cool our streets and prevent this heat from getting worse,” said Cr Bali.

 

Project Officer: David Towns

Email: This email address is being protected from spambots. You need JavaScript enabled to view it.     

Phone: 02 9839 6191

 


[1] NSW Government, Office of Environment and Heritage. (2015). Urban Heat Climate Change Impact Snapshot. Available from: http://bit.ly/2hJtErL   

[2] The Australian Government (2013, August). Environment and Communications References Committee: Recent trends in and preparedness for extreme weather events. Available from: http://bit.ly/1W1UzMD 

[3] Change in land-use from grasslands to medium density has the greatest increase in heat (0.5°C – 0.9°C). NSW Government, Office of Environment and Heritage. (2015). Urban Heat Climate Change Impact Snapshot. Available from: http://bit.ly/2hOQ76j

[4] Gallagher, L. (2014). Beyond Green Streets: Mitigating Climate Change through Residential Street Design. Available from: http://bit.ly/2hJRar3