Melbourne, Australia: Grey to Green

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Photo by David Hannah

Photo by David Hannah

Photo by David Hannah

Photo by David Hannah

Photo by David Hannah

Photo by David Hannah

Photo by David Hannah

AIPH World Green City Awards 2022 logo

City: Melbourne
Country: Australia
Award Categories:         Living Green for Climate Change IconLiving Green for Biodiversity Icon
Winner: Living Green for Climate Change Icon

* This case study was written by the city and has not been edited by AIPH

Initiative: Grey to Green

The City of Melbourne’s Grey to Green program is a compelling example of a long-term strategic and incremental approach to repurposing the city to meet the changing needs of its population. By reconfiguring sites owned or managed by Council, including surplus road space, car parks, slip lanes and maintenance depots, the city converted more than 80 hectares of asphalt into diverse public spaces over a 35-year period. Between 2018 and 2022, 12 key projects have been built and are the focus of this submission, representing more than 28000m2 of new pedestrian and green space.

Starting as a series of modest kerb expansions for additional street trees, it has become central to the delivery of Council’s open space and sustainability strategies. The recent suite of projects includes major park expansions through removal of parking, street closures, acquiring adjacent property, linear street parks and conversion of a former school ground for open space. The program continues with numerous future projects in planning and delivery.

Grey to Green was visionary from the outset. In 1985, prioritising people over cars were seen as a radical approach. The program catalysed a growing awareness of climate change impacts and informed the development of the City’s Urban Forest and Open Space Strategies in 2012, Nature in the City Strategy and Transport Strategy.   With Council’s declaration of a Climate and Biodiversity emergency in 2019 the city has cemented its commitment to realising built outcome to affect these strategic aims.

Given its relationship with these strategies, the process of a greener city transformation has been a part research-based and part design-led program. New spaces are integrated within existing public realm through high-quality design responses. From bluestone paving, new council-designed street furniture and lighting, water sensitive urban design, tree and understorey planting and integrated public art, Grey to Green areas appear as though they have always been a part of the city’s public realm. The interventions are largely subtle and small scale, helping knit the city together in a well-choreographed expression of city pride. Melbourne is now a city revitalised by its high-quality pedestrian environments where the majority of trips are made on foot. This has been achieved at modest cost through the incremental repurposing of existing space. In the Open Space Strategy 2012 it was estimated that $700 million would be required for land acquisitions to meet the strategy’s aims for open space provision, however, to date the program has only spent $1,000,000.

Grey to Green is an innovative, cost-effective and environmentally friendly model that is replicable in any city, anywhere. Its success is that it can take place on small or large scales, involving local communities in making the city a better place for people. City of Melbourne’s Grey to Green program methodology can be used by other local councils, governments, or consultants to either preserve or regain public open space and its inherent benefits. By involving multiple disciplines and the public, the program is an exemplar model for ‘good planning’ and promotes socially responsible urban design.

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Did you know?

Over 400 plant species were incorporated into the Grey to Green project.

Addressing the urban challenge

Breadth of the issue – How are the problem(s) that are being tackled by your initiative affecting citizens/local businesses or a significant component of the local wildlife?

The Grey to Green initiative addresses several key issues for the City

  1. Limited historical provision of public green space in some areas of the city
  2. Lack of permeable surfaces, canopy cover and biodiversity, and vulnerability to climate change
  3. Growing population and finite resources

Melbourne have long been a city with generous street widths; however, it was originally laid out in large blocks with all of the open space located on the edges of the central business district. The domination of buildings and roads led to a city overrun by the cars and the gradual erosion of the natural and pedestrian environment by the 1980s. The City of Melbourne’s 1985 Strategic Plan determined to reverse this trend and place greater emphasis on pedestrians and other modes of movement, making the city a more attractive destination to its residents and visitors alike.

Over time, this ‘Grey to Green’ approach has allowed the city to complement the increase in its residential population and visitor numbers with substantial increases in public open space across the municipality, providing more opportunities for recreation and improved quality of urban life for residents, workers and visitors.  Increased green space and permeable surfaces has increased opportunities for tree planting and for the improvement of growing conditions for urban vegetation. The City’s Urban Forest Strategy, highlights the benefits of additional trees and lawns on the city’s microclimate, resulting in bigger tree canopies and increased biodiversity, while reducing the urban heat island effect and contributing to climate resilience.

Depth of the issue – How seriously are the problems being tackled by your initiative impacting the life of the citizens/businesses/wildlife concerned?

Growing populations, particularly in the most densely populated areas of the city are most impacted by limited access to public open space, access to nature and quality urban streetscape.

We saw the seriousness of this issue during the extended Covid lockdowns in Melbourne where the importance was highlighted of the need for quality and proximity of local open space, and generous neighbourhood streetscapes. Those in apartments, particularly in shared accommodation or with children found this time particularly challenging.  These communities also tend to have other aspects of disadvantage that may compound their health and wellbeing and limit their opportunities to access other public spaces at a further distance.

The increased pressure of intense use of open spaces was also evident during the lockdowns when movement was limited, increasing demands on maintenance and council resources.

The diversity of types of open space and opportunities for people and urban wildlife to find refuge is an important consideration.

The power of plants and natural ecosystems to deliver benefits

How is the initiative shaped by scientific evidence of the potential for plants and natural ecosystems to deliver benefits?

Whilst the City of Melbourne’s Grey to Green initiative of incremental adaption of the City’s underutilised infrastructure and road space was initiated in the mid 1980’s, it was immediately linked with greening and has evolved to be central to the city’s strategic response to the Climate and Biodiversity emergency, enhancing community access to open space and promoting a walkable city. Over time it has grown, working in tandem with other strategies and plans as the city continues to adapt.

A research based and design led program, its delivery recognises well documented evidence of the benefits of access to open green space, plants and natural eco systems. The Urban Forest and Nature in the City Strategies outline the roles of planting to reduce impacts of Urban Heat Island Effect, flooding, and biodiversity loss. The Grey to Green projects is a primary avenue through which these strategies and their benefits are being realised.

The significant suite of projects realised since 2018 demonstrate the variety of scales and typologies involved in this approach to city adaptation including:

  • Victoria and Exhibition Street – Princes Theatre road closure – Slip lane removal
  • Southbank Boulevard, Market Street Park, Elizabeth Street South – Footpath expansions
  • Clowse Street –  Streetscape biodiversity corridor
  • Hawke and Adderley, Clayton Reserve –  Local park expansion
  • University Square, Gardiners Reserve, Lincoln Square – Neighbourhood Park expansion
  • Boyd Park – Infrastructure conversion
How has the city exploited the potential of plants and associated ecosystems to deliver more than one benefit?

Across the program the potential of plants has been exploited for multiple strategic benefits. These are noted further in the supporting documents.

Removing pavement to minimise urban heat island effects is a consistent across all the projects. Converting roads to green space, each site are considered for potential water harvesting, flood detention or passive irrigation.

Melbourne has numerous iconic public gardens and a tradition of horticultural excellence.  Ornamental planting is important to the city’s urban landscape, providing diverse structural and seasonal displays that contributes to community wellbeing and sense of place. Expansion of Victoria and Exhibition Street reserve includes rich horticulture that provides visual connections to the World Heritage listed Carlton Gardens opposite.

Informed by the city’s research into urban fauna, plant selection and artificial habitats, landscape architects and ecologists have worked together to provide resources and nesting for a range of species. Lincoln Square hosts ground nesting native bees whilst at University Square, the possum population required management for tree succession, preserving habitat and minimising grazing on the new gardens.

Connection with nature is a fundamental component of healthy childhood development. At Hawke and Adderley Reserve the native plant pallet extends into the play space with plants that are safe and robust whilst providing interest and resources for play.

In densely populated Southbank there is little access for residents to private open space, or for balcony areas to grow food. At Boyd Park the conversion of the grounds to a community park has included a communal vegetable garden.

Innovative and Collaborative Solution

How does the initiative show evidence of feasibility, including on-going financial and logistical support?

Public and political support was fostered by the incremental nature of the Grey to Green Program. The program commenced with smaller, less ‘controversial’ projects, such as the transformation of slip lanes completed successfully. These projects demonstrated the benefits of the approach before larger projects were initiated. In this way trust and confidence in the council’s approach were built over time.  The scope and scale of recent and current council works program is evidence of the value that this approach provides to enabling Council to deliver on its commitments to the community.

The longevity of this approach in adapting public road space for improved open space and greening is evidence of its feasibility as an affordable and practical way for local government to address the varied issues facing urban environments.

A forward plan of projects is already identified that will continue to address increased open space provision, access to nature and climate resilience.

Projects for Grey to Green are delivered through a variety of funding sources. By developing a co-ordinated project and design brief that addresses a variety of strategic objectives, projects may draw on funding from several areas.  Separate budgets for open space, tree planting, creation of biodiverse planting, footpath improvements and other climate responsive initiatives all contribute to these projects. Some of these funds come from development contributions associated with new subdivisions, whilst others are from general council revenue.

In what ways is the initiative innovative?

The ‘Grey to Green’ program is an innovative way of achieving more from less. Initially established to ‘encourage’ people into the central city, the program has developed and evolved over time, proving crucial in accommodating significant increases in both the city’s population and density at a notably low cost. In addition to addressing social needs, the program continues to support the realisation of biodiversity and greening targets, such as the Urban Forest Strategy which has a goal of increasing canopy cover from 22 per cent to 40 per cent by 2040. As such Grey to Green is as an adaptable program addressing a range of complex and changing social and environmental issues at the city scale.

The recognition that streets make up 80 per cent of the city’s public realm led to a two-pronged approach of expanding and improving the pedestrian environment, while requiring high-quality activation at street level, supporting the idea that ‘if you design a good street, you design a good city’.

To implement the program an Urban Design subcommittee was established, vetting all public space proposals going forward for funding consideration. Only those complying with the Program’s principles were supported. This inspired a culture of change and a co-ordinated approach across the organisation. Competing interests between Urban Designers, Finance or Traffic Engineers (concerned over losses in parking revenue) were negotiated on the basis of significant long-term savings delivered by the program.  Co-ordination continues to ensure that multiple benefits are leveraged, reducing soiling across different programs.

How is the initiative supported by collaborative working across disciplines and sectors?

The Grey to Green initiative has relied on cross disciplinary collaboration from the outset. When Council first started the program, there was some concern from the City of Melbourne’s Finance and Engineering teams regarding the potential loss of revenue through loss of metered parking spaces. Now however there is widespread acceptance that better footpaths and open space are improving property values and that Council is regaining lost revenue through the associated rates. The current policy is that on-street parking will be typically reduced by 120 per year through the program with agreement that council can accommodate that.

Further to internal and external collaboration, Prof. Rob Adams (who has overseen the Grey to Green program since its adoption) writes:
“If we had said in 1985 that ‘We’re going to take 90 hectares of asphalt out of the city’, the initiative would have hit a wall. But if you slowly take it out, it’s like slowly warming up the bath: no one really notices. Thus, Melbourne has slowly allowed itself to be transformed, to a new normal, not in favour of the car, rather people.  We slowly built credibility around managing changes, without significant impact on traffic and visible improvement in amenity. By the time we came to Swanston Street, the traffic engineers were on board and the partnership between the city and Vic Roads was well established.”

What may seem relatively straight forward is a change in strategy requiring a marathon effort by Council in partnership with many agencies and stakeholders.

How does the initiative demonstrate evidence of community support?          

Public participation is central to Grey to Green’s ongoing success and has been refined over time from Town Hall meetings to a broader engagement approach, extending to temporary road closures in the case of Southbank Boulevard to demonstrate the scale of public space that would be created through the reconfiguration of the existing road. While there was no public consultation on the formation of the ‘program’ as such, projects undergo several rounds of engagement, from concept to delivery, inclusive of one-on-one meetings with residents and local businesses. This helps facilitate exemplary outcomes by informing our understating of community needs and instilling them in the designed solutions. An example of this public consultation through the Grey to Green program is the University Square Master Plan, which involved an extensive four-phase engagement program. Here hundreds of community comments helped to shape Stage 1 of the Master Plan’s implementation, which resulted in the park expanding by approximately 2500m² and reducing asphalt within the square by over 3000m².

Grey to Green has been previously recognised in industry awards, receiving the Planning institute’s Heart Foundation award for promoting healthy cities.  This recognition by the planning profession is a key endorsement of the benefits generated by this program and its projects, including providing access to local green spaces, improved walkability, and social connection.

Individual projects within this broader initiative have also been recognised with awards, commending the leadership of City of Melbourne to undertake both modest and bold transformations of underutilised space and infrastructure.

Implementation, Impact and Replicability

How does the initiative demonstrate evidence of a track record of success against pursued objectives?          

Through the adoption of the Grey to Green program, Council’s vision of making Melbourne ‘a city for people’, ‘a connected city’, and a ‘city that cares for its environment’ is continuously being realised. In the process, biodiversity and climate adaptability have been advanced considerably. The ongoing significance of this approach is evident in the public’s utilisation of key spaces that have resulted from the program. Through Covid we have seen the increased demand on public spaces.

Data captured in the 2015 ‘Places for People’ study further demonstrates the success of the Grey to Green program and how it addresses healthy active principles. This ongoing periodic study documents the consistent increases in public space in the Melbourne municipality between 1985 and 2010, with an increase from 27 Ha to 85 Ha. While a portion of this growth (11 Ha) is due to changes in municipal boundaries over time, the City of Melbourne has gained significant additional publicly accessible spaces by extending footpaths and establishing new public places. In the last decade (between 2010 and 2020) significant public space has been reclaimed and recorded by the Council. These changes will be similarly captured in upcoming Places for People studies.

Recent feedback from residents in the north of the city recognised the value that this program is bringing to the accessibility and variety of public space that is available to local communities.  Gardiners Reserve, Lincoln Square, Hawke and Adderley Reserve and Railway Miller all serve the same neighbourhoods

How has the initiative had a ripple effect beyond the scope of the initiative itself, thereby demonstrating a change in the city’s and/or its partners’ way of working with plants?

Beyond 2022 the program of ‘Grey to Green’ continues apace. Projects currently in delivery include the transformation of Southbank Boulevard which is seeing the largest ‘grey to green’ road transformation to date with 2.5 hectares of linear public space soon to be delivered in Melbourne’s most densely populated suburb. The conversion of almost 2 hectares of asphalt for the Queen Victoria Market Renewal, as well as the addition of numerous smaller parcels of land in neighbourhoods across the municipality, continues the incremental creation of additional public space and city greening.

Many recent projects delivered through the Grey to Green approach are demonstrating a shift towards public plantings with a more diverse pallet, and that are informed by deliberate species selection for biodiversity or habitat.  City of Melbourne is partnering with the University of Melbourne in urban ecology research and monitoring of insect and other urban fauna in these landscapes to enable us to measure their success and inform future projects. The Greenline, a major council initiative seeks to revitalise the north bank of the Yarra River Birrarung in the heart of the city. This project is seeking to enhance the ecology of the riverbanks and base line ecological data is currently being measured so that the impact of future planting and other novel ecosystem approaches can be assessed.

The Grey to Green program not only proposes realistic and achievable outcomes, but it also has, and continues to be central to delivering on an innovative and sustainable vision for the city.

How have other cities expressed interest in the initiative, or what potential does it have to interest other cities and be customised to their own circumstances?

Thirty-five years on from 1985, Melbourne is a city revitalised by its pedestrian environments where the majority of trips are made on foot and in a high-quality environment. All this has been achieved at modest cost through incremental repurposing of existing space and infrastructure. Demonstrating the cumulative value of this work, Council’s Open Space Strategy estimated that $700 million would be needed for land acquisitions to meet the strategy’s aims, however only $1 million has been spent on land purchasing land over the life of the program. As such Grey to Green is an innovative, cost-effective and environmentally friendly model that can is both replicable and scalable.

The great success of this approach is that it can take place on any scale, involving local communities in making our city a better place for people. Through evaluating the vision and results of the Grey to Green program, other local councils, governments or consultants can use a similar methodology to either preserve or regain public open space and its inherent benefits. With growing density in many cities worldwide, the need to find increased open space is ever present. The cost of this space is often beyond a local government’s means, so the incremental approach of ‘Grey to Green’ is a perfectly placed methodology to address this dilemma. By involving the expertise of open space planners, landscape architects, urban designers, traffic engineers, and the public alike, the program is an exemplar model for ‘good planning’ and promotes socially responsible urban design.

Sustainability and Resilience

What efforts have been made to reduce the carbon footprint of the initiative?

Grey to Green initiative delivers carbon benefits in two keys. Through delivering on the city’s urban forest targets, the program seeks to enable the city to play a role in carbon capture, to ensure a healthy and resilient tree canopy that can support community and ecological health and wellbeing. Across the spaces delivered since 2018, more than half the area is garden bed and with over 400 plant species incorporated.

By enhancing walkability of the city, through generous pedestrian spaces that provide comfortable microclimates for people, the use of other transport modes that produce emissions is reduced. The creation of new public space on Southbank Boulevard has been enabled through reconfiguring and reducing vehicle traffic space and repurposing half of the former road to public open space. The project has also trialled the introduction of greening to the realigned tram tracks to explore the potential for reduced heat island within these infrastructure spaces. This project is enhancing walkability and promoting public transport use to support emissions production.

Council’s procurement policies and specifications also aim to reduce the consumption of carbon in the construction of city projects.  Whilst this is a work in progress, current projects such as Greenline are investigating carbon costing to inform opportunities to minimise embodied carbon and emissions.

How have the anticipated impacts of climate change been considered?

City of Melbourne declared a Climate and Biodiversity Emergency in 2019 and across all Council’s activities we are seeking to both reduce the city’s contribution to global warming and identify and address areas of vulnerability to promote city resilience.

Research commissioned by City of Melbourne’s Urban Forest team into the future suitability of tree species for Melbourne’s warming climate plays a role in species consideration for projects in the Grey to Green program. Similarly, species selection for flood prone areas of the city such as Boyd Park in Southbank have considered tolerance to inundation as well as salinity.
Diversification of species is a major aspect of the Urban Forest. strategy and projects such as Southbank Boulevard are allowing a shift from monocultural streetscapes.

In supporting the management of increased storm events, the Grey to Green approach is delivering benefits at a macro and micro level though large-scale infrastructure such as the Lincoln Square detention tank, and through increasing permeability on a local scale through small park expansions. Expansions to Clayton and Gardiner Reserves, both in low lying areas of the city, provide an important role as a soak during flood events and minimise street runoff to the nearby Moonee Ponds Creek.

What processes does the initiative include for it to be considerate in its use of soils and other natural resources?

Contamination of soil substrates of city roadways and city parks has occurred since European settlement and the development of the city. Each project involves soil testing to understand the nature of this contamination and inform both the design of the spaces and the approach to remediation.  Wherever possible, soil is retained on site and capped or remediated to address exposure for the public and improve its horticultural performance.  Examples of this are Railway and Miller Reserve and Hawke and Adderley in West Melbourne with site levels carefully managed through the design process.  Continuing work by the city’s parks and ecology teams are exploring the potential for ongoing soil improvement to assist with improved water retention, the role of soil in carbon sequestration and soil ecology. Recent projects at Lincoln Square are promoting habitat for native bees whose hives are burrowed in the soil.

Melbourne experienced more than a decade long drought from 1997 to 2009. Through this period a range of initiatives were undertaken to build the resilience of the city’s landscapes to manage water carefully.  This included designing streets and parks to increase opportunity for water capture and infiltration for passive irrigation. A number of water harvesting projects have been undertaken to reduce the reliance of city parks on potable water for irrigation. This includes stormwater harvesting at University Square and a large stormwater detention tank as part of the Lincoln Square project.

Monitoring, Maintenance, and Management

How has the initiative been designed and implemented so that long-term needs for management and maintenance are reduced and can be met?

As a council led initiative, the involvement of all teams across the organisation, including asset managers has informed the process. City of Melbourne has a comprehensive pallet of design details that have been evolved over several decades. This supports the effective maintenance of public spaces as well as ensuring their durability, quality presentation and amenity. This approach also informs new public realm that is delivered by developers for the city to meet the strategic commitments of Council.

Complexity of planting pallets and species selection are informed by input from the design team, arborists, ecologists, park maintenance and horticultural staff.  This ensures that the intent and function of the proposed planting is understood and considerations for management can inform this process.  This has enabled projects such as Clowse Street biodiversity corridor to be realised and for learnings from this to inform further enrichment to planting approaches for University Square and Lincoln Square. The knowledge of staff from across council both through technical expertise and knowledge of the city’s landscapes are an invaluable resource in informing effective outcomes that maximise public benefit whilst minimising. Many of the city’s spaces have challenging microclimates and creative

At Southbank Boulevard the planting approach has included a short-term nursery crop of fast-growing Acacia sp. to provide protection from wind to the understorey planting and people using the space until the new trees have grown tall enough to perform this function.

What protocols are in place to facilitate monitoring of results?

Strategically each development under the Grey to Green program is now executed within the framework of sustainability as laid out in the following strategic plans: Urban Forest Strategy 2012-2032; Total Watermark: City as a Catchment Strategy (2014); and Open Space Strategy (2012). In turn the program has informed the development of these strategies by leveraging the opportunities available in rethinking and reprioritising the function of streets. More specifically, converting Grey to Green spaces supports our City as Catchment Strategy by:

  • decreasing run-off
  • increasing infiltration
  • reducing stormwater volumes
  • enhancing soil moisture to supports a healthy urban forest

Similarly, converting Grey to Green spaces supports our Open Space Strategy by:

  • increasing opportunities for social connectedness
  • increasing opportunities for mental health and wellbeing
  • increasing opportunities for physical health and wellbeing
  • mitigating the urban heat island effect

Community Facilities – Grey to Green spaces, created by widening footpaths, have in many cases contributed to increased activity and safety in Melbourne’s central city. By co-locating and accommodating sidewalk cafes, fruit and food vending, flower sellers and more, service provision has been enriched, local business opportunities have been enhanced and passive surveillance, street activation and safety have been increased.

Similarly the Nature in the City Strategy has a range of initiatives to monitor species diversity, vegetation cover and connectivity across the city.  As projects are completed and plant communities establish, it will be possible to measure the ecological impact of these new green spaces.

How has the initiative been enhanced in response to monitoring of results?

Each project within the program has taken learnings from those delivered before it.  Planting pallets include a balance of reliable ‘know performers’ as well as some ‘trial’ species which allow a variety of species that may not be widely used in the city’s public spaces to be tested.

The Nature in the City Strategy is driving greater experimentation in promoting biodiversity in the city’s open spaces. A range of experimental plantings are allowing testing of different species and opportunities for research to monitor their ecology.  Partnerships with institutions such as University of Melbourne are supporting the observation of pollinators and involving community in citizen science programs to observe the use of urban landscapes by other fauna. Feedback from the city’s park maintenance teams and reviews by the city’s landscape architects also allow the teams to continually be learning about what has been working in terms of species suitability for growing conditions and maintenance regimes.

Temporary planting at University Square is testing direct seeding of meadow planting. Market Street Park has included species mixes it the permanent planting that will be insect attractors.

The complexity of adapting road spaces to open space has also been a continual process of refinement given the need to work with service authorities and other agencies who also have responsibilities for asset management within road reserves. Strategies for working around underground and overhead services as well as accommodating operational activities are allowing new projects to be realised that can maximise environmental outcomes within these parameters.