We can’t drought-proof Australia, and trying is a fool’s errand



The push to ‘drought-proof’ Australia is dangerous nonsense.
AAP Image/Mick Tsikas

Emma Kathryn White, University of Melbourne

There is a phrase in the novel East of Eden that springs to mind every time politicians speak of “drought-proofing” Australia:

And it never failed that during the dry years the people forgot about the rich years, and during the wet years they lost all memory of the dry years. It was always that way.

While author John Steinbeck was referring to California’s Salinas Valley, the phrase is particularly pertinent to Australia where the El Niño-Southern Oscillation exerts a profound influence. Water availability varies greatly across the country, both in space and time. El Niño conditions bring droughts and devastating bushfires, while La Niña is accompanied by violent rainfall, floods and cyclones.




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This variability is innate to the Australian environment. And now, climate change means that in some regions, the dry years are becoming drier and the wet years are becoming less frequent. Managing water resources under a changing climate and burgeoning population requires innovative and realistic solutions that are different to those that have worked in the past.

Drought-proofing is impossible

Planning for the dry years involves setting sustainable usage limits, using more than one source of water, efficiency improvements, managed aquifer recharge, water recycling and evaluation of the best usage of water resources. It does not involve misleading claims of drought-proofing that infer we can somehow tame the unruly nature of our arid environment instead of planning and preparing for reality.

Unlike managing for the wet and dry periods, drought-proofing seeks to negate dry periods through infrastructure schemes such as large dams (subject to huge evaporative losses) and dubious river diversions. It fails to acknowledge the intrinsic variability of water availability in Australia, and modify our behaviour accordingly.

The reality is that in many parts of the country, groundwater is the sole source of water and the climate is very dry. A cornerstone of the recently launched $100 million National Water Grid Authority is the construction of more dams. But dams need rain to fill them, because without rain, all we have is empty dams. And we have enough of those already.

A history of denial

Just because Dorothea Mackellar wrote of “droughts and flooding rains” over 100 years ago, it doesn’t mean water management should proceed in the same vein it always has.

Australia has always had a variable climate, which changes significantly from year to year and also decade to decade. This not the same as a long-term climatic trend, better known as climate change.




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Climate change is making parts of Australia even drier. Rainfall in the south-eastern part of Australia is projected to keep declining. We cannot rely on blind faith that rains will fill dams once more because they have in the past.

Yet inevitably, during the dry years, claims that Australia can be “drought-proofed” are renewed. Deputy Prime Minister Michael McCormack recently praised the Bradfield scheme, an 80 year old infrastructure project intending to divert northern river flows inland. It has been so thoroughly debunked on all scales, it is better described as a pipe-dream than piping scheme. It has no place in reasonable water management discourse.

The concept of drought-proofing harks back to the days of European settlement. Early water management techniques were more appropriate for verdant English fields than the arid plains of Australia.

In the early twentieth century, water resources were vigorously developed, with government-sponsored irrigation schemes and large dams constructed. During this time, little thought was given to sustainability. Instead, the goal was to stimulate inland settlement, agriculture and industry. Development was pursued despite the cost and ill-advised nature of irrigation in particular areas.

Shifting long entrenched perceptions of water management

All this said, irrigation certainly has its place: it supports a quarter of Australia’s agricultural output. And there are substantial efforts underway to rebalance water usage between irrigation and the environment.

However, acknowledgement of the relative scarcity of water in certain parts of Australia has only really occurred in the last 30 years or so.

Widespread droughts in the late 1970s and early 1980s highlighted the importance of effective water management and shifted long-entrenched perceptions of irrigation and development. Water reforms were passed, mandating future water development be environmentally sustainable development, which meant, for the first time, water resource management sought a balance between economic, social and environmental needs.

Antiquated ideas about drought-proofing, pushed by politicians, promise much yet deliver little. They distract attention and siphon funds from realistic solutions, or actually re-evaluating where and how we use our limited water resources.




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We need practical, effective and well-considered management such as water recycling, efficiency measures and source-divestment that accounts for both shorter term climatic variability and long term changes in temperature and rainfall due to climate change. A big part of this is managing expectations through education.

Attempting to drought-proof Australia is not “managing for the dry periods”, as advocates claim. It is sticking our heads in the dry, salty sand and pretending the land is cool and green and wet.The Conversation

Emma Kathryn White, PhD Candidate, Infrastructure Engineering, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Our land abounds in nature strips – surely we can do more than mow a third of urban green space



Even the standard grassed nature strip has value for local wildlife.
Michelle/Flickr, CC BY-NC-ND

Adrian Marshall, University of Melbourne

You may mock the national anthem by singing “Our land abounds in nature strips” but what you might not know is how true that is. In Melbourne, for example, more than a third of all public green space is nature strips. (That figure includes roundabouts, medians and other green bits of the street.)

That’s a remarkable amount. The nature strip is everywhere. A million small patches combine into a giant park spanning the city, making it a significant player in our urban ecosystems.




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A second remarkable thing is that the nature strip is public land that private citizens are required by law to maintain. Councils manage the trees, but we residents mow the lawn.

What are the rules on nature strips?

Succulents, Agapanthus and Gazanias are the most common plantings on nature strips.
Adrian Marshall CC BY 4.0, Author provided

Many residents go further and plant a street tree or some garden plants – succulents, Agapanthus and Gazanias are the most common. But the chances are that, whatever the garden on the nature strip, it’s against the rules.

The rules on nature strips vary from council to council. Some councils don’t allow any plantings. Others restrict plantings by height or allow only plants indigenous to the local area. In some areas, nature strips can only be planted to prevent erosion on steep slopes.

Some councils disallow food plants, for fear of historic lead contamination from leaded petrol. Others insist on no plants within a metre of the kerb and two metres of the footpath.




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These bylaws are inconsistent and illogical. For instance, councils that insist on indigenous species nevertheless plant exotic street trees. Councils that say plants must be less than 30cm high to ensure they don’t block drivers’ sight lines still allow vehicles to park on the street, blocking sight lines.

Bylaws deny us many benefits

To have council bylaws restrict or disallow gardening in the nature strip flies in the face of common sense. Street greenery, whether its trees, shrubs or lawn, provides many benefits. The science is in on this.

Urban wildlife uses street greenery for habitat and food and as green corridors for movement.

Even for those who mow, the lawns of nature strips are not just turf grass. They are home to over 150 species of plants, based on my yet-to-be-published survey data for nearly 50 neighbourhoods, confirming earlier studies. Many of these, like the clovers, provide important resources for pollinators.

One US study showed that changing from a weekly mow to every three weeks increased the number of flowers in a lawn by 250%. Less mowing is good news for bees and butterflies.

An unpublished recent survey by the author and colleagues found gardening in the nature strip adds native plants to the streetscape, increases biodiversity and add structural complexity (more layers of plants, more types of stuff), which is important for many species.

The greater the diversity of plantings, the greater the benefits a nature strip can provide.
TEDxMelbourne/Flickr, CC BY-NC-ND

Street greenery helps water soak into the ground, filtering out pollutants, recharging aquifers and making rivers healthier. It cools streets and helps counter the urban heat island effect. It also promotes a sense of community, encourages walking and lowers the incidence of heart disease, diabetes, asthma and depression.




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But councils tend to be risk-averse. They worry they will be sued if someone trips on groundcover or stubs their toe on an out-of-place garden gnome.

Fortunately, this risk aversion isn’t universal. For instance, the City of Vincent in Western Australia is so keen for residents to convert lawn to waterwise plantings that it will remove turf and provide native plants.

But, as climate change looms, stubbed toes are not the main risk we should be worrying about. Rather, we must urgently remake our cities and our culture for sustainability and resilience.




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Gardening becomes a neighbourly act

One of the great things about gardening in the nature strip is that people are more likely to do it if their neighbours do it. It’s contagious, a positive-feedback loop creating a greener street.

Our recent survey found residents who garden in the nature strip have a greater sense of community than those who don’t.

A well-designed street garden, fully covering the nature strip, allowing pedestrian access to cars and using indigenous plants.
Adrian Marshall CC BY 4.0, Author provided

Interestingly, the benefits nature strips provide are not equally distributed across the city. For instance, newer neighbourhoods have more nature strip than older neighbourhoods (though their trees are younger). People garden the nature strip more on minor roads than major roads, and in more socially advantaged neighbourhoods.

Almost a quarter of residential properties in Melbourne have some sort of nature strip gardening. If councils were to encourage this activity we might achieve more street greening with little cost to our cash-strapped councils. Such encouragement would also free many residents of their sense of frustration at being required to maintain the nature strip but forbidden to do anything more than mow.

Given that more than a third of our public green space is nature strip, the many small actions of residents can add up to substantial positive change.The Conversation

Adrian Marshall, Lecturer, Landscape Architecture and Urban Ecology, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.