The Kambruk Wetlands An ecosystem-based solution to the impending pressures of a changing climate Edward Howe Monash University Project no. 18 Urban Planning and Design The Krambruk Wetlands The Krambruk Wetlands offer an settled areas from the impacts of Wetlands are incredibly beneficial The present condition of Apollo Bay opportunity for Apollo Bay and storm surges, as the energy that is and ever-increasingly precious and Marengo is not static - it is a Marengo to mitigate the impacts of released down the Barham River in environments for the world that are moment produced from a larger a number of the mounting pressures the Otway Ranges is dissipated in facing loss as the worlds oceans collection of interwoven histories that that threaten the physical and cultural the wetlands. An expanded wetland rise. They are powerhouses in will ripple out and continue into the fabric of the connected coastal towns. network with an educational nature carbon dioxide storage and can act future. These histories - geological, By expanding the existing marsh walk showcase and promotes will as filtration devices, cleaning water climatic, ecological and social, both inland into the low-lying Barham provide an additional attraction for as they collect sediments when Indigenous and European - have River floodplain through careful day-tripping tourists along the Great watercourses slow and emerge to the shaped the land and those that wetland creation, a freshwater marsh Ocean Road, marking Apollo Bay as ocean.1 The opportunity that Apollo interact with it, and any plan for the environment can be nurtured that a destination itself rather than just a Bay’s topographical nature presents area must consider and anticipate will anticipate a rising sea level and lunch stop on the way to the Twelve for an expansion of its current these larger-scale processes and a greater expanse of the floodplain Apostles. Residents of Apollo Bay and wetlands can not only attend to the regard their current environments in a becoming tidal. These impending Marengo will enjoy access to this quiet community’s most pressing issues, state of flux. processes are a certain future, and retreat all year round, as the dynamic but also serve a grander narrative by pre-empting them the Wetlands nature of the wetland seasonally in global wetland conservation and can bring a multitude of benefits to and as it changes with the tide will propogation. the area and ensure a harmonious serve to connect residents with these and well prepared for transition. The sensitive and essential environmental increased capacity can buffer the processes. The Great Ocean Road surround a few of the settlements dotted along the Road. Apollo Bay and Marengo notably distinguish themselves from the rest of the other settlements through their elevation. While Lorne, Anglesea and the other smaller coastal hamlets that front the Otway Ranges share the steep topography of the mountainous area, Apollo Bay and Marengo are comparatively flat, with the land slowly rising in terraces to an elevation of The Great Ocean Road winds down sometimes forgotten genesis of the 30 metres after a kilometre from the the coast, passing through a handful eroding Apostles2 encapsulates the shore at the settled areas widest point. of quiet coastal hamlets and larger geological and climatic cycles that In contrast, at Lorne’s widest point, tourist hubs, before cutting inland the region and the world face as the settled area begins a kilometre across Cape Otway and meeting the the oceans again rise, escalated by from the shore at an elevation of 140 coast again along its most iconic point, human activity. As the Great Ocean metres before steeply descending. as the sheer drop of the sedimentary Road runs along a coastline that is in This low-lying characteristic of the limestone cliff faces make way for parts eroding and in others subject dual-towns has resulted in a geological the Twelve Apostles. Formed under to submersion, a question mark is heritage of unconsolidated sediment, the pressure of the ocean when raised above its future in the wake of of a high susceptibility to erosion by a submerged in recent millennia, the it’s centenary.3 The same questions wild Southern Ocean. The Barham River and Project Area The Barham River rises in the Ranges that struggle to meet demand in peak and deposits into the ocean just south season.4 In these low-flow times, the of Apollo Bay in Mounts Bay, after estuary mouth is often closed and meandering through a large floodplain environmental flow levels are required between Apollo Bay and Marengo. The to be met as the limited capacity of the river is the sole fresh water source for existing wetlands dries up. The Great the two towns, as well as servicing Ocean Road crosses the Barham Skenes Creek, to the north of Apollo River and runs between the eroding Bay. The flow of the Barham River, coastline and the existing wetland, and therefore the availability of fresh while the Barham River Road runs water, is highly seasonal, with huge parallel to the river. These two key rains collecting high in the Otways roads have been flooded in instances and feeding the Barham from the of high storm tides as a result of the streams and rivers that comprise its low elevation and limited slope, and tributaries. The two branches of the have cut off the access of the towns river feed into two water storages from each other. Barham River and streams Other major rivers Existing roads Current wetland extent 10m contours Coastline (current) Water storage Coastline vulnerable to erosion Pressures to Waters Rising Opportunities and Falling sq Expanding the existing wetland area lity ue Victoria’s projections for sea level rise ibi ez into the Barham River flat seeks to pt ed adhere to a uniform 0.82 metres by e h c s a address the 5 identified issues that b 2100 across the state - a prediction u i s ta face Apollo Bay and Marengo now which is considered in the Victorian d t s o o and into the future. The created Coastal Strategy 2014 to be a f Krambruk Wetlands will not serve to reasonably conservative one, while still mitigate the negative effects of these indicating that the level is expected to 5 phenomenons wholly, but will act in rise beyond that. These generalised y part of a wider strategy of various t levels point to a need to prepare for i l i projects across the wider Apollo Bay b a more brackish flat of the Barham a area aimed at reducing the impacts a r River, as well as indicating that if left e p of these factors and preparing the n unattended to, a storm event would i l t - u residents for the future. s v threaten the southern settled sections t o t p h of Apollo Bay, flooding the caravan g The wetlands will act as a dissipator of to u park and oval, and the north-eastern o w r the wild storm energy that rushes the n d most properties of Marengo behind area in the wetter months, protecting 2100 - 82cm the foreshore. These predictions dont 2070 - 47cm rs the settled areas from flooding, e te 2040 - 20cm account for regional variability - it is ncroa ng wa 2009 - while also serving to increase the chi 00cm understood that sea level rise can environmental storage capacity for occur in different rates depending on the drier months, relieving the town latitude and temperature6 - and more from its most pressing summer crisis. importantly also don’t account for the As the sea rises, habitat space for erosion susceptibility of Mounts Bay. a few of the Great Ocean Roads The coastline will undoubtedly change vulnerable species will be squeezed, drastically in the near future, and the and by identifying and expanding into status of the Barham River Estuary accomodation space inland from the as an intermittently open river mouth wetland, the species that thrive in will likely change as the ocean and the current freshwater habitat of the wetlands find paths to meet over the wetlands will be preserved before current dunes. the water becomes too brackish. The resulting ecological refuge can act to This realignment of the coastline will attract tourists for a further stay in the doubtlessly result in a loss of the gross area. wetland area and the increasingly saline environment as the projections 2100 1 in 100 year flood indicate will overtake the existing 2070 freshwater area. Much speculation 2040 2009 surrounds the future of coastal Projected sea level rise (top) and storm tide with 1 in 100 year flooding (bottom) y t i n n i o In Belgium, the Hedwidge Prosper In the UK, the process of recreating coastal As the sea level rises, l i t depolderisation (above, left) removed wetland environments is called ‘managed sediment that travels a a previously constructed coastal defences in coastal realignment’, and existing defences downstream can collect s t order to mitigate the severity of flooding in are withdrawn to allow rising waters to enter and gather as the slow n the surrounding settled areas, opening these low-lying regions.11 flow of the river moves d e lands to the tides and reestablishing the further upstream and e 10 s natural estuarine environment. the total wetland area m a i increases. This can lead e d to vertical accretion of r e c the sediment, neccessary s to propogate vegetation n wetlands as the sea level rises, but An eco-system based approach i there is a general consensus that to the issue of sea level rise is above the water line.