The north shore picnic spot hot enough to cause skin burns

Far from providing a cool spot to sit, the plastic turf masquerading as grass in Chatswood Civic Centre’s Concourse can be hot enough to cause skin burns.

That makes it a liability, Willoughby councillor Kristina Dodds has warned.

Dodds has called on the council to remove the plastic grass because “temperatures have been recorded at over 60C on a 28C day”.

The square is also at the heart of one of the north shore’s major entertainment hubs where films are screened, people picnic and students take a break from studying in the library. 

The motion asks council to urgently consider replacing the artificial grass with a non-plastic safe alternative: “Plastic grass can in summer months reach extremely high temperatures exposing the public, and particularly children, to the risks of heat exposure and burns.” Dodds cites research showing that artificial turf can reach 72 degrees, compared with 39 degrees for real grass.

Playgrounds with black and dark-coloured wet pour rubber and synthetic turf, which had different types of plastic grass, were the hottest floor materials, the journal Building and Environment reported. They had maximum surface temperatures greater than 80 degrees.

On the verge of a suburban Chatswood street, Dodds discovered fake grass that was as hot as the black bitumen on the adjacent road.

An urban heat study commissioned by the council from Western Sydney University found “stark thermal differences” across the LGA, with air temperatures reaching 46 degrees in some areas. Using more than 100 temperature loggers, it showed extreme heat was an issue in a suburb such as Chatswood, as well as in the east of the city, near the harbour, and in the west.

All councils faced trying to mitigate the impacts of urban heat, but it was far from a “one size fits all” solution, said WSU urban heat expert Professor Sebastian Pfautsch.

He said other local governments were trying to identify and quantify the size of the problem too. Sydney, Blacktown, Parramatta, Cumberland, Campbelltown and Penrith were doing studies, while Northern Beaches has completed a partial study that focused on Brookvale.

“What these councils had in common was that they didn’t expect the large variations we document in microclimates across their jurisdiction, especially during days when heat is extreme.

“Yet every LGA has its ‘specialties’. For example, the harbour breezes in Willoughby or the City of Sydney, the cool air drainage in Parramatta at night, or the very hot new suburbs like Marsden Park in Blacktown.”

It was not without conundrums. “Cooling interventions need to be targeted. Urban spaces are complex,” Pfautsch said. “Take the Concourse. It is the second-hottest place around Chatswood due to its materials, colours, absorbance and reflectance of heat, the lack of shade.

“But because the place has unobstructed sky above, it is the coolest place in the evening and at night – heat just radiates back into space, no trapping under trees or shade sails.”

Willoughby Mayor Tanya Taylor did not comment ahead of Monday night’s meeting to discuss the matter.

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