The debate around the Murray-Darling Basin is often sharply polarised: irrigation is destroying the environment, or water reforms are ruining farming communities.
But there is another story. In the Riverina region of southern New South Wales, a strange waterbird is using rice fields to live in and breed.
The endangered Bunyip Bird, also called the Australasian Bittern, is famous for its deep booming call – for thousands of years thought to be the sound made by the mythical Bunyip.
It’s a sound now familiar to most rice growers. In 2012, Birdlife Australia and the Ricegrowers’ Association teamed up to learn more about bitterns in rice. The total bittern population, including New Zealand and New Caledonia, is estimated at no more than 2,500 adults.
Why a wetland might not be wet
The first question was how many bitterns are using rice crops. After surveying the birds on randomly selected farms, we crunched the numbers. Our results, just published, are staggering.
Across the Riverina, we conservatively estimate these rice crops attract 500-1,000 bitterns during the breeding season, about 40% of global population. It turns out the way rice is grown provides ideal water depths and vegetation heights for bitterns. It’s also favourable for their prey: frogs and tadpoles, fish and yabbies.
There is a growing body of global research investigating how human-made habitats can help fill the gap left by our vanishing wetlands, from ditches for rare turtles to constructed ponds for threatened amphibians. Rice fields around the world show great promise as well, with various “wildlife-friendly” farming initiatives. In California, farmers re-flood harvested fields to support thousands of migratory shorebirds and waterfowl, while in Japan consumers pay a premium for “Stork Rice” to help endangered species.
However, rice fields are no substitute for natural wetlands, and it’s now clear both play a crucial role in sustaining the bittern population.
Satellite tracking has shown us that at harvest time bitterns disperse to some of southeastern Australia’s most important wetlands, including the Barmah-Millewa system along the Murray River, Coomonderry Swamp near Shoalhaven Heads in New South Wales, Pick Swamp in South Australia, and Tootgarook Swamp on the Mornington Peninsula near Melbourne.
Rice farming in Australia’s Riverina has a century-long history. The amount grown varies greatly from year to year, depending on water allocations, and ranged from 5,000-113,000 hectares over the past decade. Around 80% is exported and it provides food for up to 20 million people each year.
Driven by water efficiency, many rice growers in the Riverina are switching their methods to intermittent flooding and not “ponding” the water – maintaining inundated fields – until later in the season.
A shorter ponding period will likely reduce opportunities for the bitterns to breed successfully before harvest. Another threat to bitterns is farmers switching to alternative crops and horticulture, none of which provides them habitat.
During the 2017-18 irrigation season, there was more cotton grown than rice for the first time in the Riverina. It’s usually simple economics: irrigators will generally grow whatever gives them the best return per megalitre of water, with their choice having no net effect on the overall amount of irrigation water used in the system.
Water management in the Murray-Darling Basin is complicated, with fluctuating temporary water prices and trading between catchments. Water is allocated to either agriculture or the environment, setting up a dichotomy. But we think allocations to serve a single purpose may be overly simplistic, and the way bitterns use rice offers a case study for considering multi-purpose water use.
Working closely with growers, we are identifying ways to develop cost-effective incentive programs for bittern-friendly rice growing, where a sufficient ponding period is provided, with complementary habitat on banks, in crop edges and adjacent constructed wetland refuges. The aim is to boost the bittern population with the help of rice farmers.
We are also surveying consumers about their attitudes towards bittern-friendly rice. Would you pay a premium for rice products that offset additional costs to growers for bittern conservation? How do you feel about adjusting water and conservation policies?
Bitterns are not the only threatened species that use the Riverina’s rice fields. The endangered Southern Bell Frog and Australian Painted Snipe have also adapted to rice crops, and it’s likely there are significant populations of other species too.
With 61% of Australia managed by farmers, the need to incorporate wildlife conservation on farms has never been greater. We hope our work will help address the divisive, sometimes toxic debate around water use in the Murray-Darling Basin, uniting irrigators and environmentalists.
Matt Herring, PhD Candidate, Charles Darwin University; Kerstin Zander, Associate professor, Charles Darwin University; Stephen Garnett, Professor of Conservation and Sustainable Livelihoods, Charles Darwin University, and Wayne A. Robinson, post doctoral research fellow, Charles Sturt University
The Conversation/Wikimedia Commons, CC BY-SA
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River red gums, Eucalyptus camaldulensis, are among the most iconic of Australia’s eucalypts. They are the most widely distributed of all the eucalypts. They grow along rivers, creeks, waterways and flood plains where many Australians like to picnic, so most of us get to know and love them.
Formerly known as Eucalyptus rostrata, the species was one of the first eucalypts encountered in parts of Australia by European settlers. Curiously, the name camaldulensis comes from the Italian monastery of Camaldoli near Naples, where a specimen grown from seed in a private garden was given the name Eucalyptus camaldulensis in 1832. No one knows how the seed got to be there!
River red gums can be very large spreading trees with huge trunks more than 5 metres around. In parts of Australia, such as along the Murray River, they can be very erect trees reaching more than 45m tall.
Most specimens have smooth bark with a mottling of multiple colours ranging from creams to orange and red, but there may be a skirt of fibrous grey bark for the first few metres of the base. They are called river red gums because they grow along rivers and their wood when freshly exposed is a bright red; almost blood-coloured.
River red gums have been used by Indigenous people for canoes, bowls, shields, and other utensils. The wood is red is because it contains very high levels of chemicals such as polyphenols, which are a natural antiobiotic when combined with air.
These chemicals not only protect the living tree from disease and some pest attacks, but make the timber very durable. These chemicals meant river red gums were used for medicinal purposes by Indigenous people. The wood has been widely used for railway sleepers, fence posts, and piers and wharfs where durability and water resistance are desirable. They have been widely planted overseas and in some countries pose a serious weed problem.
The trees can have very long lives, and may reach 1,000 years of age. They grow very rapidly when conditions are favourable and so become large trees quite quickly. But as they get older it is very difficult to age them without damaging the tree and putting it at risk of disease and decay. So their ages are estimated, as no one wants to be responsible for killing a grand old tree just to confirm its age!
Older specimens almost always develop large hollows, which can take centuries to form. The hollows provide refuges for birds, mammals and reptiles. The nesting sites are often raucously defended by brightly coloured parrots. The trees and the nectar from their small white flowers are also very important for honey production – a large tree in full flower over the warmer months can attract so many bees that the whole tree can be heard humming from many metres away; it’s a wonder the tree doesn’t take off.
At certain times of the year, often during summer, river reds can be very heavily grazed by insects to the point where their leaves are skeletonised. The trees look as though they are about to die, but they are very resilient and a few months later most are back to a full and healthy canopy. Another insect, the psyllid, also feeds on and skeletonises the leaves. It has a sweet, waxy covering called a lerp that protects the vulnerable insect nymphs beneath. Some Indigenous groups scrape off the lerps, roll them into a ball, and eat them like a lolly.
Any tree that can live for a millennium must be adaptable, so like some other eucalypt species, river red gums can shed up to two-thirds of their foliage when soils dry out during a drought, which reduces water demand and prevents the trees from wilting. This shedding often causes people to complain about the trees when they grow in towns and cities, but when the rains come a few months later they rapidly produce new leaves and are soon once again in full canopy.
River red gums can tolerate immersion in flood waters for up to nine months. They do this by having extensive roots, some of which contain a spongy, air-filled tissue called aerenchyma that allows for the accumulation and transport of much-needed oxygen in waterlogged soils. This adaptation to stressed soils also means river red gums can do quite well in disturbed urban soils when the urban sprawl impinges on their natural domain.
River red gums readily seed after flooding events and great numbers of young trees may germinate. However, relatively few survive to maturity due to competition from other red gums, other trees, and weeds. They may also struggle to survive in some places due to a lack of water.
Because river reds occur in some of the driest and harshest parts of the Australian mainland, you might think they are very efficient users of water. However, nothing could be further from the truth. The trees can have very deep, spreading and searching root systems, which tap into subterranean water, even if the water is many metres from the trunk. They are luxury water users with very little capacity for water use control. If water becomes really limiting, they simply wilt.
E. camaldulensis produces a water-soluble chemical that is washed from its leaves by rain. These chemicals inhibit the growth of other plants, including river red gum seedlings, under the canopy. This phenomenon is called allelopathy, and along with a dense canopy inhibits plant growth under the trees. These chemicals are washed from the soil by flood water, which makes way for the germination of seedlings after floods. This is a wonderful mechanism that ensures seedlings do not germinate when conditions are dry and where they would compete with the parent tree for limited water, but germination is facilitated when there is plenty of water and soils are wet.
Some people think river red gums are dangerous because they shed large limbs without warning on calm, still, summer days. There is no doubt this does happen, but there is no clear evidence they shed limbs more often than other species.
The problem is complex, because they tend to grow everywhere people want to go. They provide shade along waterways on a hot, dry continent. In going to places where the trees grow, people tend to compact the soil with their vehicles and footpaths, which can be causes of limb shedding. The compaction of the soil affects soil moisture and aeration, which can lead to limb shedding.
In other contexts such as farms where limbs are shed, many old river red gums are growing in highly disturbed or changed ecosystems. Furthermore, many of these remnant specimens are often stressed and getting older and so more prone to shedding.
River red gums trace the watercourses of mainland Australia, and are easily seen from aeroplanes as you cross the continent. They connect the continental fringes with its arid heart. Their lives can span many human generations and it is nice to think that the majestic old trees that pull at our heartstrings have done the same to previous generations and, if we and they are lucky, will continue to do so for generations of Australians yet to come.
The Australian construction industry has grown significantly in the past two decades. Population growth has led to the need for extensive property development, better public transport and improved infrastructure. This means there has been a substantial increase in waste produced by construction and demolition.
In 2017, the industry generated 20.4 million tons (or megatonnes, MT) of waste from construction and demolition, such as for road and rail maintenance and land excavation. Typically, the waste from these activities include bricks, concrete, metal, timber, plasterboard, asphalt, rock and soil.
Between 2016 and 2017, more than 6.7MT of this waste went into landfills across Australia. The rest is either recycled, illegally dumped, reused, reprocessed or stockpiled.
But with high social, economic and environmental costs, sending waste to landfill is the worst strategy to manage this waste.
With the right tools, we can mine cities
What’s more, China introduced its “National Sword Policy” and restricted waste imports, banning certain foreign waste materials and setting stricter limits on contamination. So Australia’s need for solutions to landfill waste has become urgent.
China has long been the main end-market for recycling materials from Australia and other countries. In 2016 alone, China imported US$18 billion worth of recyclables.
Their new policy has mixed meanings for Australia’s waste and resource recovery industry. While it has closed China’s market to some of our waste, it encourages the development of an Australian domestic market for salvaged and recycled waste.
But there are several issues standing in the way of effective management of Australia’s construction and demolition waste.
In Australia, the main strategy to reduce the waste sent to landfill is the use of levies. But the effectiveness of levies has been questioned in recent years by experts who argue for smarter strategies to manage waste from construction and demolition. They say that imposing a landfill levy has not achieved the intended goals, such as a reduction in waste disposal or an increase in waste recovery activities.
One effective strategy Australia should expand is extended producer responsibility (EPR).
The idea originated in Germany in 1991 as a result of a landfill shortage. At the time, packaging made up 30% by weight and 50% by volume of Germany’s total municipal waste stream.
To slow down the filling of landfills, Germany introduced “the German Packaging Ordinance”. This law made manufacturers responsible for their own packaging waste. They either had to take back their packaging from consumers and distributors or pay the national packaging waste management organisation to collect it.
Australia has no specific EPR-driven legal instrument for the construction and demolition waste stream, nor any nationally adopted EPR regulations.
But some largely voluntary approaches have had an impact. These include the national Product Stewardship Act 2011, New South Wales’ Extended Producer Responsibility Priority Statement 2010 and Western Australia’s 2008 Policy Statement on Extended Producer Responsibility.
These schemes have provided an impetus for industry engagement in national integrated management of some types of waste, such as e-waste, oil, batteries and fluorescent lights. Voluntary industry programs also cover materials such as PVC, gypsum, waffle pod and carpet.
For instance, since 2002, the Vinyl Council of Australia has voluntarily agreed to apply EPR principles. Armstrong Australia, the world’s largest manufacturer of resilient PVC flooring products, collects the offcuts and end-of-life flooring materials for recycling and processing into a new product. These materials would otherwise have been sent to landfill.
In another example, CSR Gyprock uses a take-back scheme to collect offcuts and demolition materials. After installation, the fixing contractor arranges collection with CSR Gyprock’s recycling contractor who charges the builder a reasonable fee.
But extending producer responsibility in a sustainable way comes with a few challenges.
Everyone in the supply chain should be included: those who produce and supply materials, those involved in construction and demolition, and those who recover, recycle and dispose of waste.
The goal of our work is to connect organisations and industries across the country so waste can be traded instead of sent to landfill.
But the lack of an efficient supply chain system can discourage stakeholders from taking part in such schemes. An inefficient supply chain increases the costs associated with labour and admin staff at construction sites, transport, storage, separation of waste and insurance premiums.
All of these are not only seen as a financial burden but also add complexities to an already complicated system.
Australia needs a system with a balanced involvement of producers, consumers and delivery services to extend producer responsibility.
In our research, we’re seeking to develop a national economic approach to deal with the barriers preventing the effective management of construction and demolition waste in Australia, such as implementing an extended producer responsibility.
And a project aimed to find ways to integrate supply chain systems in the construction and demolition waste and resource recovery industry is supporting our efforts.
The goal is to ensure well-established connections between all parts in the construction supply chain. A more seamless system will boost markets for these materials, making waste recovery more economically viable. And that in turn will benefit society, economy and the environment.
Salman Shooshtarian, Research Fellow, RMIT University; Malik Khalfan, Associate Professor, Property, Construction and Project Management, RMIT University; Peter S.P. Wong, Associate Professor and Associate Dean, School of Property, Construction and Project Management, RMIT University; Rebecca Yang, Senior Lecturer, Property, Construction and Project Management, RMIT University, and Tayyab Maqsood, Associate Professor in Project Management, RMIT University
Nations behave wisely, Israeli foreign minister Abba Eban observed five decades ago, “once they have exhausted all other alternatives”.
One can only hope that proves the case with water policy in Australia’s Murray-Darling Basin, the nation’s largest river system and agricultural heartland.
The ABC’s Four Corners program Cash Splash, aired last night, illustrates how thoroughly we are exhausting the options that don’t work to keep rivers being sucked dry by irrigators. Billions of dollars have been spent on infrastructure schemes that have failed to deliver any measurable improvement in water flows or the state of the environment.
This failure is no surprise to economists who have studied the problems of the Murray-Darling Basin for decades.
The central problem is well understood, as are the workable (and unworkable) possible responses.
The basin covers four states: Queensland, New South Wales, Victoria and South Australia. All state governments have allocated permits to extract water for human uses (irrigated agriculture and urban water). The allocations grew rapidly in the second half of the 20th century, exceeding the sustainable capacity of the natural environment.
One sign of the failure became dramatically obvious in 1991, with an outbreak of toxic blue-green algae over 1,200 km of the Darling River. Algal blooms are fed by nitrogen and other nutrients in fertiliser runoff and sewerage. They continue to occur.
This event underlined the need to leave enough water in rivers for “environmental flows” to keep the system healthy.
Acting with what now seems like impressive promptness, the Murray-Darling Basin Ministerial Council (made up of the water resources ministers from the basin states, the Australian Capital Territory and the federal government) imposed a cap on water extractions in 1995. It limited extractions to the volume of water capable of being taken out by the infrastructure (pumps, dams, channels, management rules) that existed in 1993-94.
The cap was supposed to be a temporary measure. It wasn’t intended to solve the problem, just stop it getting any worse in the short run.
The long-term solution was to be a system of trade in water rights, introduced by the Council of Australian Governments in 1994. Combined with the right price signals from environmental purchases, this system was meant to allocate water to its most productive uses while reducing extractions to sustainable levels.
A quarter-century on, the cap is only now being phased out, and a vast array of measures have come and gone, including the National Water Initiative, the Water Act of 2007, Water for the Future and the Murray-Darling Basin Plan.
The failure of these initiatives rests on one simple fact: the refusal of irrigation lobby groups to countenance the government buying water rights on the open market to increase environmental flows. Their opposition has been immovable, despite many individual irrigators being keen to sell their water rights and use the money to invest in alternative cropping activities or retire.
On the other hand, there are a lucky (often politically well-connected) few who have done very well from “strategic” purchases of water. Investigative journalist Michael West has noted the National Party’s Barnaby Joyce has been publicly hostile towards buybacks of water entitlements but authorised, as federal water resources minister, three major “strategic purchases”.
Instead of water purchases, politicians like Joyce have put their faith in subsidies to infrastructure, to improve the efficiency of water use.
The idea has a lot of intuitive appeal. If less water can be used, it should be possible to increase flows in the river system without reducing agricultural output. With rare exceptions, this appealing vision has dominated the thinking of politicians and much of the public.
The reality is sadly different. The failure of infrastructure-based water recovery was both predictable and predicted.
Is the Murray-Darling Basin Plan broken?
I pointed out the main difficulties in a piece for ABC Online in 2012. The article didn’t contain any remarkable insights. It simply stated views shared by every independent economist who has worked on the issue.
Among the many problems with infrastructure schemes, two have stood out.
First, the measured cost of saving water through infrastructure schemes is two to three times as much as that of buying water on the open market.
Second, and more importantly, much of the supposed water savings are illusory. Much of the water “wasted” in irrigation systems is not lost to the environment. Most of the water leakage and seepage from irrigation channels eventually returns to rivers through groundwater systems. So “saving” this water through infrastructure efficiency doesn’t actually add anything more to environmental flows.
My 2012 analysis assumed a scientifically based effort to secure water savings at the lowest possible cost to the public. As the Four Corners report has shown, that assumption was massively over-optimistic. In reality, the scheme has been characterised by lax monitoring, cronyism and rorting.
After the expenditure of billions in public money, the system may be worse off than before. As a result, environmental disasters keep on happening.
Along with recurring algal outbreaks, we are witnessing disasters such as the massive fish kills like that in western New South Wales in January. The massive fish kills have been attributed to little or no flow in the Darling River combined with plunges from high temperatures, starving the water of oxygen.
As the riverine environment keeps deteriorating, there’s no sign of any positive change in policy.
Eventually, though, we must hope Abba Eban will be proved right. Having exhausted all the options that don’t work, we will have to turn to those that do.
Indonesia has returned a container load of recyclables back to Australia, because the material did not meet stringent import requirements.
It is the latest Southeast Asian country to refuse Australia’s recycling waste. In January 2018, China stopped buying our recyclables until contamination was reduced significantly.
To achieve this, Australia needed to reduce contamination in commercial and household recycling, and improve our sorting facilities so they can identify and remove the types of materials causing concern.
This should have been a wake-up call that we need to improve our recycling industry and take urgent steps to reduce our reliance on overseas destinations for our recyclables. But did we? Clearly, the answer is no.
In July the Philippines turned away 69 containers (about 1,500 tonnes), of materials incorrectly labelled as plastic and containing unacceptable contaminants. Malaysia has also threatened to send recyclables back to the originating country if the loads contain contaminants.
Looking at photos of the material rejected by Indonesia, it is clearly a typical load of baled recyclables that could have come from any sorting facility in Australia. It contains recyclables, but also contamination like used nappies, clothing, food scraps, paper and cardboard in the plastic recycling, metals and plastic in the paper recycling and some containers that once had motor oil or detergents in them.
While I personally suspect it’s slightly over the top to call this “hazardous” material, as some news reports have – the same loads are shipped to some facilities in Australia – it is a moot point. Indonesia can set whatever rules they deem necessary to protect the health of their communities and environment.
This continues after strong warnings that unless we provide clean recyclables, we will not have access to these overseas markets.
Recycling is basically divided into “streams”. Mostly these streams contain one or two types of materials. For example, we have a cardboard stream, plastic stream or in some instances commingled stream which contains plastic, aluminium, steel and glass containers.
“Contamination” refers to materials that are not wanted in that stream because they interfere with the proper treatment of a given load. Plastic in a load of cardboard and paper is contamination; so are clothes in a plastic load. It does not necessarily need to be toxic chemicals or other things that come to mind when we think of “contamination”.
However, containers used for detergents, disinfectants, and the broad range of household chemicals do contain residues. While some of these fluids and powders do get removed (often while materials are being baled), some residues remain and this can also cause issues for those wishing to use the recyclables as their raw materials.
So it is no wonder Australian businesses are reluctant to use what we currently sort and send out as their raw materials. If the recyclables materials contain contaminants at a high level, then the business who could have used them would have to expend resources to clean up the loads. Apart from that cost, they then have to dispose of the unwanted materials to landfill.
Additionally, due to some uncertainty in the quality of the recyclables, manufacturers are concerned whether their products will be of the required standard and if not, will that affect the customer base. Remember, when recycled paper was first on the market there was some concern about inferior “whitness” and this affected sales. (Ironically, now most business use recycled paper this situation is somewhat reversed.)
Ultimately, the issue is not how we can get other countries to accept our waste. Australia needs to improve our capacity and willingness to use recycled materials ourselves.
We have seen progress recently with Australian companies using recycled materials in new and innovative ways. Plastics used in road construction or in building materials is just one example.
But unless our recycling is better sorted, it won’t be used by domestic companies. Even products made with recycled material need to be clean, safe and reliable.
So what can we do about it? Of course, the obvious first step is to invest more into recycling facilities so they can sort more efficiently. However, we all need to take responsibility for what we put into the recycling at home or work. Many contaminants can easily be avoided with a little more care, so familiarise yourself with what can be recycled by your home council.
Finally, recycling is not a panacea. We need to seriously reduce the amount of waste we create, as individuals and a society. Without this, the problem will only continue to grow.
We can’t recycle our way to ‘zero waste’
Greening our cities has become one of the great global imperatives of the 21st century including to tackle climate change. And Australia’s sprawling car-based cities are gradually changing to embrace green or living infrastructure.
Green cities bring together elements of architectural design and urban planning, often combining plants and built infrastructure to meet the needs of humans, such as our love of nature.
Trees, plants, waterways and wetlands can deliver climate conditioning, cooling cities by reducing the urban heat island effect. They also absorb carbon dioxide, filter wastewater and create habitats.
Living elements can be incorporated with built infrastructure at a range of scales, from individual buildings with green walls and roofs, through to citywide strategies. And there are a suite of strategies to guide more widespread integration of biological elements and ecological processes in cities.
In recent months, we profiled Australian examples of living infrastructure that show some of Australia’s approaches to developing green infrastructure, from greening Melbourne’s laneways to Canberra’s urban forest. These cities are already redesigning their water systems and implementing urban forest strategies to create green belts and protect and restore waterways.
Melbourne and Canberra provide some useful examples of the green cities movement, but to make it mainstream, these techniques need to be adopted widely through policies supporting more holistic and better integrated urban planning.
Percival Alfred Yeoman was one of the first Australian pioneers of urban forestry. In 1971, he articulated a clear vision for enhancing cities with trees.
Local governments in Adelaide, Brisbane, Melbourne and Sydney, are implementing his ideas, committing to ambitious increases in urban canopy cover. Their targets range from 25% to 40%.
This revived interest in urban forestry comes from its well documented potential for accelerating the transition to more climate adaptive cities.
The social, environmental and economic benefits of urban trees, or “ecosystem services”, are becoming better recognised, including for their recreational and cultural values.
Melbourne has a rich legacy of urban parks and green belts thanks to planning decisions made in the city’s early years.
These parks underpin a new wave of urban greening, with projects that aim to deliver action on climate change, biodiversity and the health and well-being of communities.
The Melbourne green infrastructure plan includes:
a “growing green guide” that provides practical advice to community and business groups on planning, design and maintenance of green infrastructure
the greening laneways strategy, which builds on the commercial revitalisation of Melbourne’s laneways over three decades. Laneways with greening potential were mapped and demonstration project developed to display techniques for making them more vibrant green spaces for business, tourists and locals to enjoy
an urban forest strategy, with an overall target of 40% canopy cover by 2040. And 5 to 8 million trees will be planted over coming decades for the greater Melbourne metropolis.
Canberra is often described as “a city within a landscape” and the “bush capital”. But its higher altitude, hot dry summers and cold winters bring a set of challenges for green infrastructure.
With more than 800,000 planted trees, Canberra is an urban forest. But these trees require special care and attention given they are ageing and suffering from a hotter, drier climate.
Wildfire also represents a significant risk where urban and rural areas connect. This means Canberra needs urban forests that will cool the city in warmer months without also escalating wildfire risks.
The ACT Government has committed to action on climate change, legislating targets for 100% renewable electricity by 2020 and carbon neutrality (no net carbon emissions) by 2045.
Greening cities requires a holistic approach – for instance, not leaving the health of waterways entirely to water engineers.
Greening cities is more than just a technical challenge. Transforming the form and functions of urban systems, through urban forests and other living infrastructure, requires greater leadership and political commitment, integrated planning and community participation, and long-term thinking.
An integrated approach to greening cities involves mapping diverse opportunities and mobilising support for change in the community. As an example, urban storm water can be a productive resource when used in constructed wetlands or to irrigate urban forests.
And often urban drainage lines and wastelands can be transformed into green spaces, but it’s worth recognising there is intense competition for space for housing.
But for more widespread adoption of integration, institutional support within local governments and metropolitan water and planning agencies is needed.
So to scale up living infrastructure in our urban landscapes, we must learn from local success stories, conduct more research, and better understand how to deal with climate adaptation and mitigation challenges.
Jason Alexandra would like to gratefully acknowledge the contributions of Barbara Norman to this article.