From Carparks to Creeks: What It Takes to Make Cooler Places Work

What we learned from Cumberland City Council and T.C.L at the September 2026 Place Leaders Community of Practice.

Extreme heat is coming. It's a design, public-health, infrastructure, risk, and governance challenge. How will cooler places get approved, engineered, funded and maintained, and still perform all of their other place roles? A carpark still has to provide parking. A flood channel still has to carry floodwater. What happens when we also ask these places to provide shade, habitat, safer connections, and a cooler everyday experience?

That was the practical question behind Place Leaders Asia Pacific’s Heat, Trees and the Politics of Risk: How Cooler Places Get Delivered Community of Practice on 18 September 2026.

Kar Gan, Associate at T.C.L, took us to Breakout Creek / Purruna Pari Stage 3 in Adelaide and Natalie Gray, Coordinator Environmental Management at Cumberland City Council, shared the story of the Cumberland Cool Carparks at Holroyd Gardens in Merrylands and the Kingsway commuter carpark in Wentworthville. Natalie’s colleague Eshita Dutia, Principal Smart Places and Place Development Officer, also joined the discussion, contributing lessons from the Kingsway installation and its handover to Council’s maintenance teams.

The session brought together practitioners, researchers, elected representatives and public-sector leaders from Australia and New Zealand.

Here's what we learned.

1. Keep the essential function but make room for more

Breakout Creek is the coastal end of Adelaide’s River Torrens / Karrawirra Pari and its constructed channel carries floodwater through the western suburbs towards the sea. Stage 3 could add wetlands, habitat, paths, public access and cultural interpretation, but the corridor still had to perform its flood-management role. The wetlands are modelled to treat about 60 million litres of stormwater each year and prevent approximately 95 kilograms of nitrogen from reaching Gulf St Vincent. The project opened about 15 hectares of previously fenced land to the community, including 11,400 square metres of permanently vegetated wetlands, more than 6.2 kilometres of paths and trails, five viewing decks, an accessible boardwalk and a new river crossing. In 2026, Breakout Creek / Purruna Pari Stage 3 received the 2025 Place Leaders Environmental Placemaking Award.

Cumberland faced a different non-negotiable: its vine-covered structures could cool selected areas of two working carparks, but they could not remove any parking bays beneath them - no loss of parking was a key constraint.

“Different organisations need confidence in different parts of the outcome.”- Kar Gan

2. Bring evidence into the design while choices remain

Kar described a process in which technical advice influenced the landscape as the plan developed. Flood questions were considered with engineers and water specialists while the design choices were still open. The same approach was taken when the team encountered the roots of mature river red gums: during construction, arborist investigations showed where paths and wetland works could affect important trees. T.C.L adjusted levels and shapes while keeping routes usable for wheelchair users, people with prams, and maintenance vehicles. One example was the low-level pedestrian crossing. Hydraulic modelling by Tonkin informed its height and form, with the design allowing water to pass over the crossing during high-flow events. This was a deliberate trade-off between improving everyday access and retaining the river’s flood function.

At Cumberland, evidence began with heat mapping and where is was most severe. Western Sydney is highly exposed to urban heat, and Cumberland has a growing population, low canopy cover, and extensive hard surfaces. Western Sydney University developed low-cost sensors that recorded air temperature every 10 minutes over 110 days. Council deployed 108 heat loggers across the LGA, giving the team a detailed picture of where intervention was most needed. Council’s work with Western Sydney University identified carparks as some of the hottest local microclimates. Across Western Sydney, more than 2,200 carparks were unshaded in 2020, and dark asphalt can approach 70°C on very hot days. At Holroyd Gardens, Council, Western Sydney University, and Tensile Design and Construct tested a trellis and vine structure over selected parking bays. Cumberland reported that shade from the vines reduced asphalt surface temperatures by more than 40°C. Air beneath the vines was up to 2.5°C cooler than in the sun, while human thermal comfort improved by about 10°C.

3. Treat prototypes as a way to learn

The first Cool Carpark demonstrated that a living canopy could shade asphalt without removing parking spaces, and also revealed what needed to improve for the second installation. The original horizontal structure established slowly and the vines did not distribute evenly across the roof. At Kingsway, the team tilted the roof, improved the automated irrigation arrangements, and used white-painted steel to reflect more sunlight. The angled form helped the vines climb and spread. After 22 months, the second structure had reached 71 per cent vine coverage and created about 100 square metres of shade. The second installation also benefited from an existing water connection beside the carpark. Automated irrigation reduced the burden on Council crews during the critical establishment period. Western Sydney University and the contractor supported early pruning and replacement of plants before the asset team took on the longer-term routine.

“Always do your due diligence, get all the approvals, cross your t’s and dot your i’s.”- Natalie Gray

4. Design the ongoing maintenance and governance with the same focus as the opening day

The audience’s most persistent questions concerned long-term care and maintenance for both projects. Who waters the vines? Who prunes them? How do environmental outcomes survive ordinary asset-management systems?

At Cumberland, both structures sit on Council land, but their contexts are different. Holroyd Gardens is a closely managed destination park with staff regularly on site. Kingsway is a commuter carpark near a railway station and receives a different level of everyday attention. Natalie described the handover as a practical process: document the completed project, record the lessons, explain the maintenance needs, and transfer responsibility to the relevant Open Spaces team. The project officers still checked the structures when they were nearby and followed up if they saw a problem. A formal handover was important, but informal relationships across Council were also critical.

Breakout Creek required a broader governance arrangement. The site crosses the City of Charles Sturt and the City of West Torrens, while SA Water manages the flood levees. Green Adelaide led a partnership that also involved government funders, specialist consultants, contractors, and community interests. Kar explained that shared design principles gave the partners something to return to when COVID-era working conditions, construction costs, and delivery expectations shifted. The councils agreed on a maintenance approach for this section of the corridor, and the project included a three-year contractor maintenance period. That establishment period allowed new planting to mature and showed council teams what care would be needed monthly, quarterly, and annually.

A key take-away was that the person supporting an idea, the person assessing it, and the person maintaining it may sit in different teams or organisations. Their perspectives need to meet before the major choices are locked-in.

“Bring the people who will access, build, and maintain a place into the conversation while there are still choices to be made.”- Kar Gan

5. Community input / update is always critical

Community engagement at Breakout Creek ran from early concept design through later design and construction stages. One story Kar shared showed why that engagement continuity mattered. Budget and constructability pressures nearly led the project team to drop the creek crossing and elevated connection. During consultation, local families explained the value of an uninterrupted route between the neighbourhoods on either side of the creek. With primary schools on one side of the creek and a high school on the other, families saw the connection as a safer route that avoided busy arterial roads. That feedback was very clear evidence of the public benefit of connectivity.

At Holroyd Gardens, Council issued notifications to nearby residents and maintained a 'Have Your Say' page during design and construction. A former member of Cumberland’s engagement team explained that QR codes at the carpark directed people to updates, research, and funding information. People could see what was happening and why.

Natalie also emphasised that no parking bays were lost. That removed an obvious source of community concern: Council was adding a new layer of green infrastructure while the carpark continued to perform its everyday function. This made the trial easier to explain and understand.

What can place leaders do next?

The session ended with practical advice. Natalie urged practitioners to investigate the sites carefully, confirm approvals and identify basics such as access to soil and water. For councils without current heat evidence, she suggested starting with data collection and seeking a research partner who can help identify where an intervention will make the greatest difference. Kar emphasised transparency between clients, consultants, engineers and contractors.

Both Natalie and Kar emphasised the need to identify what existing place roles must be protected. The lesson was that cooler places succeed when their existing place functions are understood, their performance is measured, and responsibility for their future maintenance is designed in from the start.

Place Leaders Asia Pacific Community of Practice brings practitioners together to get behind the finished projects, share what changed during delivery, and apply those lessons to other places.