Topos 81 Murray Darling article

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Water Landscapes

Singapore Blue- Green Infr a st ruc t ures · Mekong Delta Water urBa nIsm · Japan dIsa ster pre ventIon By dy n a mIte · new ZealanD post Indust rI a l Wat erfron t In auc k l a nd · auStralia murr ay da rlInG rIver syst em · China We t l a nd pa rk In H a nG zHou · Spain restor atIon of a rIver l a ndsc a pe In Ba rcelon a · Slovenia renovatIon of t He rIver Ba nk s In l juBl ja n a · FranCe rIver l a ndsc a pe of t He seIne In pa rIs · new York Waterfront projec ts · FloriDa restorInG t He e verGl a des · liMa Water-sensItIve cIt y de velopment



Caitrin Daly, Ricky Ray Ricardo

Murray Darling On the driest inhabited continent on earth, water management

is serious business. The Murray Darling Basin, australia’s largest and most complex river system, exists on an environmentally fragile knife-edge. With debate intensifying in recent years, it is worth asking how landscape architects are contributing to it. 43


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Lake Mokoan, a former irrigation source in Victoria’s north east, was decommissioned in 2009 to re-establish the Winton Wetlands (landscape architecture: Taylor Cullity Lethlean). Subsequent years of healthy rainfall has seen a rapid improvement to the ecology of the area. The photo on page 43 shows the place where Lachlan River reaches Great Cumbung Swamp which once drained to Murrumbidgee River.

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he Murray Darling Basin comprises one-seventh of the continent’s total land area, stretching from southeast Queensland to southern Victoria, and taking in much of New South Wales as well as parts of the Australian Capital Territory and South Australia. It is a landscape that dramatically reflects changes in climate patterns. From extreme drought to years of rain and floods, the river has evolved to deal with these prolonged climatic events, and its associated ecosystems have relied on this cycle for millions of years. Despite this, the basin has the role of generating as much as 40 percent of Australia’s agricultural income through its burden as a staple irrigation source. Algal blooms, salinization, extreme climatic events, competing political agendas, and policy after policy regarding water management all feature regularly as news items for the river system. Seeing as we landscape architects often define our profession as one which is concerned with understanding the complexity of natural systems, we should be well placed to design concepts and solutions that transcend ongoing policy wrangling, providing perspectives that not only rely on pragmatism but work to engage both environmental and economic agendas. While some exist, it must be noted that there are surprisingly few architectural projects, built or speculative, that approach the particular challenges in the Murray Darling system. It seems that perhaps the profession must more actively assert itself as a credible resource in the process of combatting such diabolical landscape disasters, and put forward a greater contribution to this critical debate. European settlers did not understand the complexity and importance of the Murray Darling system’s dynamic nature when they first began to cultivate the area for agriculture. The agricultural practices of the time saw large-scale land-clearing along the riverbanks, the drainage of vital wetlands, and the construction of weirs and dams to feed irrigation and mitigate flooding – effectively transforming once wild, variable rivers into regulated irrigation channels. This was highly detrimental to the estuarine ecosystems that relied on regular flooding. The degradation of water quality through nutrient influx from farming practices and salinization from the rising water table has become a highly concerning issue, causing greater instances of algal blooms and spoiling vast tracks of viable land. With huge amounts of water lost to evaporation, efficiency in water management was and continues to be a key part of the problem. The sun is hot in this part of the world, and its rays are unforgiving. Inefficient practices such as open channelling and spray and surface irrigation are common, and are responsible for large amounts of water being wasted each year. All of these factors have contributed to an unbalance in this fragile system, culminating in widespread environmental destruction, ecosystems disappearing, and the spread of salinity and erosion. What has ensued is decades of tension



between irrigators, environmentalists, policymakers, and scientists over how best to curb the decline of the system. Projects are now emerging which are attempting to combine programs and confront competing agendas. This may be the key to achieving a new typology and balance between what appear to be diametrically opposed positions. Wetland recovery projects are beginning to take place throughout the basin; however, these generally do not involve the participation of landscape architects and designers. Such projects, while their ecological benefit is undeniably positive, often fail to win praise from the farming community. It is a commonly held view that redirecting water from agriculture to the environment will lead to the collapse of local communities. The Winton Wetland project in northeastern Victoria is fundamentally different. It also happens to be the largest project of this kind to be undertaken in the southern hemisphere – and perhaps one of the most significant globally.

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The Mildura Riverfront proposal by McGregor Coxall uses water-sensitive urban design initiatives to treat storm water from the city before it enters the Murray River. The design also allows for the natural processes of the site, such as the shifting of the river’s edge.

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andscape architects Taylor Cullity Lethlean (TCL) won the commission to develop a master plan for the Winton Wetlands – formerly Lake Mokoan – which is due for public release late 2012. Lake Mokoan was constructed solely as an irrigation source in 1971 over what was previously a network of ephemeral swamps. It is interesting to note that the catalyst for the retirement of the lake, announced in 2004, was not only environmental concerns but also cultural issues. A site of huge indigenous importance (covering three language groups), fertile agricultural land, and hundreds of thousands of River Red Gum trees were flooded in creating the lake – Victoria’s fifth largest water storage. However, with an area of 7,880 hectares and a deepest point of just seven metres, the lake was prone to high evaporation rates and regular outbreaks of toxic blue-green algae. Work began on the decommissioning in 2009, and thanks to consecutive years of above-average rainfall, the re-established wetland environment has flourished. The re-establishing of wetlands has allowed for the return of 44,000 megalitres of water per year to the Broken, Goulburn, Snowy, and Murray Rivers, with environmental and economic benefits to both upstream and downstream areas. In regard to the wetland itself, the master plan developed by TCL also involves a detailed business model, seeking to provide the project with an economic footing to assist the wetlands in becoming an “eco-tourism” attraction that should provide the region with a stimulus, offsetting any negative effects surrounding the decommissioning of Lake Mokoan. This project demonstrates the importance of assessing how particular land uses perform across a range of scales, and how working with, rather than against, ecological processes can benefit the economy as well as the environment.



Tidal Garden (Richard Black, Times Two Architects) would provide visitors with Landscape Walk

an immersive experience of the estuary landscape at the mouth of the Murray River in South Australia. Through a number of walks that traverse the constantly shifting threshold between land and water, the design seeks to highlight and work with the dynamic processes occurring in the landscape.

Landscape Walk

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he Mildura Riverfront proposal by McGregor Coxall uses waterUrban Walk sensitive urban design initiatives as a means of replicating pre17 development water cycles on the banks of the Murray River. Though minuscule in relation to the vastness of the basin, their design for a riverside park draws on a thorough understanding of the water-flow issues associated with the larger river system, allowing for the river’s edge to shift. Using design features that replicate an equivalent natural hydrological landscape, the park aims to provide a dynamic and interactive recreational and environmental precinct. It would enable living environmental systems to re-establish and have the capacity to filtrate stormwater harvested from urban catchment. Perhaps the most significant aspect of the proposed park’s contribution to the wider river system is that of generating public awareness. It has the potential to provide visitors with an insight into the history of the river and the effects of inert river-edge management techniques and reduced river flows. The Mildura Riverfront project has the added benefit of establishing significant tourism opportunities, generating new economic stimulus and local business opportunities. This project highlights the potential of landscape architecture as a tool which is able to re-establish relationships with environmental systems in a way that satisfies competing agendas. This ground is rich with opportunities where meaningful environmental remediation can be coupled with the structural transformation of townships – from singular

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rban Walk

irrigation-dependent economies to more resilient and sustainable economic models. The challenge is to enable an intimate understanding of the site’s dynamic and ephemeral processes through experience.

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recent speculative project, Tidal Garden by Richard Black (Times Two Architects), explores the potentials of uncertainty in the constantly shifting landscape around the mouth of the Murray River. This project is the culmination of Black’s PhD entitled Site Knowledge in Dynamic Contexts, which began with the question: “What are the consequences for a range of architectures of living with the River Murray, rather than living against the River Murray?” The work is positioned to provide discussion on the effect of a return to greater variability in water flows on river towns and the land uses that presently occupy floodplains. Importantly, it proposes a future where land use and ways of inhabiting a floodplain do not compete with its ecological processes. Tidal Garden is sited on a disused grazing property in an estuary landscape at the mouth of the Murray River. The speculative proposal consists of a series of landscape and infrastructural scale interventions that intend to work with the river’s rehabilitation. Amphibious architectures were developed along three walks, each conceived from the constantly shifting lines traversing the water’s edge. Each walk is described as “embodying a condensed understanding of the river system and its land-

scape, along with a political and ethical stance of how to intervene in such circumstances.” Drawing on an intimate understanding of the Murray River system, this project seeks to develop an architecture that poetically makes visible the dynamic processes occurring in this particular landscape. Through its embrace of site conditions, particularly the ephemerality of water in the estuary, the design is allowed to constantly evolve through the action of flooding, tidal movement, and rising sea levels. By providing an immersive, aesthetic experience, the Tidal Garden offers visitors a greater recognition and respect for the surrounding landscape and the wider river system. While operating at different scales, these three projects demonstrate the potential of design to reconcile ecological concerns and create economic opportunities. They successfully work with the dynamics of the river system, while also beginning to address the economic interests of townships facing a future with reduced entitlement to the resource they have built their prosperity on. These landscapes seek to immerse us in the narrative of natural process, creating a respect for place and allowing for remediation to occur within new typologies. From the local scale to the territorial, landscape architecture has an important voice that provides new perspectives on enduring problems, making our profession relevant to the ongoing discussion surrounding the Murray Darling Basin and other contentious landscapes around the world.


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