The Kambruk Wetlands an Ecosystem-Based Solution to the Impending Pressures of a Changing Climate

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

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

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

and into the future. The created l 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

part of a wider strategy of various t levels point to a need to prepare for 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) tide. migration inpreparation oftherising have identifiedcorridors forwetland the DepartmentofNatural Resources wetland migration. based solutionsinanticipationofa into wetlandsthroughcarefulnature- determined accommodationspace consensus ontheadaptationof implemented, howeverthereis that havebeenconcievedofand little inthewayofreal-worldprojects space andwetlandmigrationhave to sealevelrise,accommodation understanding ofwetlandsinregards more marine. As arecentlynew a coastalenvironmentbecomes as thefuturesiteofwetland to thewetland-at-risk,soasserve by thepreservationoflandadjacent environments canbesupplemented on thecoastofpreciouswetland the wetlandtomigrateinto. sufficient ‘accommodationspace’ for is determinedbytheavailabilityof their currentecologiesintothefuture the resilienceofwetlandstomaintain there isageneralconsensusthat wetlands asthesealevelrises,but natural estuarineenvironment. lands tothetidesandreestablishing the surroundingsettledareas,openingthese order tomitigatetheseverityoffloodingin previously constructedcoastaldefencesin depolderisation (above,left)removed In Belgium,theHedwidgeProsper 9 8 InMaryland,USA, 10

7 Loss low-lying regions. are withdrawntoallowrisingwatersenter coastal realignment’,andexistingdefences wetland environmentsiscalled‘managed In theUK,processofrecreatingcoastal An eco-systembasedapproach from. approach fromwhichto moveforward utilising anecosystem-based of floodandsealevel risemitigation to thesea,theyoffer afoundation involve theopeningof theestuary defences norinitsinitialstages involve theremovalofhardstructural Krambruk site,whichdoesnot different environmentstotheproposed While theseprojectsareinmarkedly conditions beforehumanintervention. water inordertorecreatetheprevious allow thedrainedareastorefillwith been removedorretreatedinlandto These dykesandpoldershavesince solutions tokeepcoastalwatersout. of allwaterthroughhardstructural environments thatdrainedtheland human interventionsonwetland examples ofpreviouslyconstructed wetland migration,therearenumerous real-world precedentsofdeliberate and tomaintain.Whilethereareno defences canbecostlytoimplement literature, asstructuralcoastal widely appreciatedincontemporary to theissueofsealevelriseis 11

the BarhamRiver. sediment-rich flowsuchas a decade,butpossiblein process thatcantakehalf above thewaterline. A to propogatevegetation the sediment,neccessary to verticalaccretionof increases. This canlead the totalwetlandarea further upstreamand flow oftherivermoves and gatherastheslow downstream cancollect sediment thattravels As thesealevelrises, 12

Egret Great Eastern

propogation Mangrove increased Potential of sedimentation Greyling Australian increased salinity 1. The Archerfields 1 2 Wetland Discovery Trail will attract and Tourism and Ecology educate. 2. Modified wetlands at the Werribee Treatment Plant host a thriving display of fish and bird-life that attracts international eco-tourists.

3+4. The Eastern Great Egret and the Australian Greyling a both vulnerable species whose 3 4 A wetland can serve as an attraction interaction with the environment while habitats can be greatly to tourists and a retreat for residents only covering a small footprint of the expanded upon in the alike - those human and those area as a whole.13 Krambruk Wetlands. more vulnerable. Conservation and 5. The swamp scrub protection of the species most at risk The Great Ocean Road will need to be ecological vegetation in the area is crucial, but the sensitive rerouted, or raised. The road cannot class is collected on development within the wetland can afford to erode, or become inundated, the partially inundated also be implemented to educate as it provides an economy of upwards portions of the wetland. and teach about these values of of $1 billion per annum. A realignment 6. The nearby Aire conservation, and the impermanence does not only serve the tourist pocket River offers bountiful of the environment. but will also relieve the stress of a tourist opportunities squeezed habitat, a phenomenon with conditions similar The huge amount of biodiversity caused by a lack of buffer space to that of the proposed wetlands. and ecological significance found in surrounding an area of significant 5 6 wetlands, as well as the associated biodiversity due to a presence of 7. A raising of the activities with aquatic activities such infrastructure and urbanity.14 Allowing Great Ocean Road as fishing, boating and birdwatching, room for a habitat to breathe in a akin to NSW’s Sea attract visitors seeking to reconnect whole patch rather than divided Cliff Bridge should be implemented in order with nature. This almost happened by a road or human infrastructure, to relieve the coastal by accident in the case of the promotes a healthy environment within wetland from ‘habitat Werribee Treatment Plant, with the which are the measures for resilience squeeze’. byproduct of the wetland environment and regeneration should a particularly maintained through waste treatment dry season result in a limited-flow 8. Mangroves are hugely beneficial in becoming a thriving habitat for local occurrence, and in the case of the trapping and stabilising and migrating bird life. A balance Barham River, significantly threaten sediments required for between conservation and public use the vulnerable freshwater Australian wetland migration. is necessary to maintain sustainable Greyling. Diverting the Road in such tourism, and wetlands often guide a way will create a tourist attraction in 7 8 the human impact in contained areas of itself, adding another feature in the while still retaining the qualities scenic Great Ocean Road drive. that make the visit worthwile. The proposed Archerfield Wetlands in Brisbane makes a case for a similarly squeezed wetland habitat in an urban environment, and has a particular focus on the delivery of a “nature- focused Adventure Park”, with a raised 1km boardwalk enabling inclusive The Proposed Wetlands

Barham River Existing roads Proposed roads Proposed Wetland vegetation extent Proposed wetland water extent 10m contours Coastline (current) Water storage

The proposed wetlands will be a The Barham River Road and the Great significant extension of the existing Ocean Road will need to be realigned: wetland system, known as ‘the the former, initially as the land is Backwater’. Depressions and prepared for wetland migration; and channels will be created upriver of the latter, as soon as possible, to allow the Backwater, where the 1 in 100 for the environment room to develop year flood prone area, also the land naturally and to anticipate an eroding affected by a Flooding Overlay, shoreline. Possible options for the marks the accommodation space for Great Ocean Road include remaining the freshwater wetland squeezed on its current trajectory but raised, or out by the rising sea levels. The diverting out to sea over Mounts Bay. Barham River will seasonally fill these depressions and channels with water, Community consultation should follow each time accreting sediment that will and be integral to the development allow the spread of vegetation. of the Krambruk Wetlands, informing decisions regarding the Swamp scrub vegetation should development of the wetlands from be encouraged to propogate in this the initial proposal through to the immediate hinterland, while as the physical development to the ongoing lower-lying areas become more tidal reassessments. and saline over time, mangroves can be planted and nurtured in those areas Key stakeholders include: more completely submerged with • The Great Ocean Road Parks and saline water, with the soil level gaining Coast Authority height over time through continued • The Eastern Maar Corporation sediment collection. • Barwon Water • Colac Otway Shire A boardwalk can be constructed in • Parks Victoria the Backwater initially, and perhaps • The Department of Land, Water following establishment of the inland and Planning wetland after time can be extended, • VicRoads following the route of the Barham • Current landowners River Road and connecting to Apollo Bay to Marengo. Policy and Planning

General Residential Neighbourhood residential Low-density residential Commercial 1 Industrial 1 Public conservation and resource Public park and The majority of the site area is works relating to watercourse recreation agricultural land within the Rural management and those serving to Road Rural activity Conservation Zone, which limits improve environmental conditions, 20 Rural conservation the land use to rural activities that performed by a public authority. The Special use prevent soil erosion, increased schedule to the overlay states the Public use (various) salinity and vegetation removal.17 significance of the low-lying Barham A permit is required for earthworks River area as one of high ecological that affect surface water runoff and importance. The hills surrounding those that potentially discharge Apollo Bay are of landscape saline groundwater. The Barham significance, and the Significant River extends from the Otway Landscape Overlay aims to preserve Ranges National Park and carries and highlight the open terraces that The complex web that is the current area of Apollo Bay, Marengo and the same Public Conservation frame the Bay before the Ranges rise situation of public land management Skenes Creek.16 The 250mL Apollo and Resource Zone with it for the up.21 along the Great Ocean Road has Bay basin that was opened in 2014 extent of its run, the highest level resulted in the formation of a Great to complement the 125mL Marengo of environmental conservation A few legislative changes are required Ocean Road Taskforce, aiming basin has since proven to be not zoning, restricting development to to be made in order to expand upon to consolidate and streamline the as future proof as expected, with low impact developments by or on the existing wetland area inland to management of the land while being severe drought conditions across behalf of Parks Victoria or other create the Krambruk Wetlands. The able to formulate policy to focus on the 2015/16 summer “worse than public land authority, and usually entire site area should be within a the area as a holistic system.15 The anything experienced in the Millennial those supplementary to education on Public Conservation and Resource alignment of values of the Great Drought”. Under a high-impact climate the natural environment.18 Overlays Zone, to ensure the protection of the Ocean Road Action Plan with those change scenario, the current 375mL further limit development on the site land for the benefit of the environment. of the Krambruk Wetlands project - of water storage will meet demand in area, significantly the Land Subject Flood mitigation and works of namely surrounding holistic thinking 2024, and is particularly susceptible to Inundation Overlay, which controls environmental improvement endorsed and conservation - serve the project to short-term shocks as the seasonal the size of development and the by a public authority are allowed in the to be opportunely situated within the extremes of wet and dry result in effect on surface water runoff on existing wetland area, but not in the Action Plan. The consolidation of the full stocks in winter when the river the floodplain, as well as limiting the proposed wetland area. To overcome public park and coastal land under flows and a reliance on storage in the residential use of the land.19 Flood this a protection of land projected a new authority - the Great Ocean summer when the river is dry. The mitigation works such as those that to transition to wetland can be Road Coast and Parks Authority - will strategy highlights a renegotiation would encompass the creation of the legislated in a Coastal Retention Zone, manage the wetland as it transitions of bulk entitlements as a considered Krambruk Wetlands are exempt from implemented first through a Wetland from freshwater to more saline as the measure to ensure water security. The the building and works restrictions. An Migration Strategy by the Great Ocean tide rises. increased capacity of the wetlands Environmental Significance Overlay Road Parks and Coast Authority. This presents an opportunity for water to covers the flat of the Barham River land use mechanism can be used to Barwon Water’s Urban Water be held in the winter for environmental and its estuary, protecting the ecology retain land that is adjacent to coastal Strategy 2017 highlights the ongoing flows, allowing the service region to of the area through further restrictions environmental assets to prepare it for capacity issues with servicing the increase the level of bulk entitlements. to development, but again exempting future migration and adaptation. Implementation Timeline I II III

2026 Development of acquired properties Ongoing seasonal 2023 upstream to create fill and sedimentary The development of the Krambruk Wetlands will occur across three major Amend planning freshwater wetland. Rains deposit for wetland phases. The first phase involves the neccessary preparations needed to create scheme to create new to fill dug channels and vegetation propogation the wetlands. The second phase deals with the physical development of the 2022 Coastal Retention depressions seasonally wetlands and supplementary projects. The third phase is ongoing and involves Zone to reserve with heavy winter rains. Acquisition of the continuing management of the created ecology into the future. accommodation space properties in the project for future wetland 2029 area and compensating 2025 enviroments along Extending of land owners according to natural corridors. Beginning of wetland walk to the Land Acquisition and community consultation newly developed Compensation Act 1986. for the scope and wetland areas deisgn of the wetlands

2019 2070+

Ongoing Assess the Creation of the Great Development Establish a ‘wetland Rerouting of implementation potential of opening Ocean Road Parks and of Coastal Wetland walk’ in existing wetland, Great Ocean Road reviews to assess the estuary out to Coast Authority as outlined Migration Strategy. along with additional potentially out to sea future wetland sea further as the in the Great Ocean Road tourist infrastructure. depending on sea decisions berm is expected to Action Plan (2019). level rise coastal 2023 2026 reconfigure erosion impacts. 2030+

Understake 2060 2020 2028 detailed flood, Realignment of sea level rise, and Barham River Road sedimentation assessments. 2028 2025 Increased salinity of existing and created wetland areas as the project area becomes more brackish.

2019 2040 2070 0.0m 0.2m 0.47m

Projected Sea Level Rise References 1 Jeffrey Kelleway, Kerrylee Rogers, and Neil Saintilan, ‘Rising Seas Allow Coastal Wet- lands to Store More Carbon’, The Conversation, http://theconversation.com/rising-seas-allow- coastal-wetlands-to-store-more-carbon-113020. 2 Andrew Trounson, ‘Discovered: The Drowned Apostles’, Pursuit, 9 March 2016, https:// pursuit.unimelb.edu.au/articles/discovered-the-drowned-apostles. 3 Lisa Cox, ‘Great Ocean Road at Risk from Erosion and Rising Sea Levels, Report Finds’, The Guardian, 11 January 2019, https://www.theguardian.com/australia-news/2019/ jan/11/great-ocean-road-at-risk-from-erosion-and-rising-sea-levels-report-finds. 4 Barwon Water, ‘Barwon Urban Water Strategy 2017’ (Barwon Water, March 2017), https://www.barwonwater.vic.gov.au/water-and-waste/urban-water-strategy. 5 Victorian Coastal Council, Victorian Coastal Strategy 2014., 2014. 6 Stijn Temmerman et al., ‘Ecosystem-Based Coastal Defence in the Face of Global Change’, Nature 504, no. 7478 (December 2013): 79–83, https://doi.org/10.1038/nature12859. 7 Mark Schuerch et al., ‘Future Response of Global Coastal Wetlands to Sea-Level Rise’, Nature 561, no. 7722 (September 2018): 231–34, https://doi.org/10.1038/s41586-018-0476-5. 8 Ibid. 9 National Oceanic and Atmospheric Administration, ‘Shifting Shorelines, Shifting Con- servation Strategies: Assessing Wetland Conservation Priorities in Maryland’ (September 2011) https://coast.noaa.gov/data/digitalcoast/pdf/shifting-shorelines-maryland.pdf 10 ‘Hedwige-Prosperproject’, Sigmaplan,, https://www.sigmaplan.be/nl/projecten/hedwige-prosperproject-en-doelpolder/deelprojecten/hedwige-prosperproject%20/. 11 CoastAdapt, ‘Managed coastal realignment projects in the UK: ‘Working with nature’ (2018), https://coastadapt.com.au/sites/default/files/case_studies/SS46_UK_Coastal_Realign- ment.pdf 12 Riccardo Brunetta, João Salvador de Paiva, and Paolo Ciavola, ‘Morphological Evolu- tion of an Intertidal Area Following a Set-Back Scheme: A Case Study From the Perkpolder Ba- sin (Netherlands)’, Frontiers in Earth Science 7 (2019), https://doi.org/10.3389/feart.2019.00228. 13 Oxley Creek Transformation, ‘Archerfield Wetlands – Precinct Plan’, 2018. 14 Sinéad M. Borchert et al., ‘Coastal Wetland Adaptation to Sea Level Rise: Quantifying Potential for Landward Migration and Coastal Squeeze’, ed. Jason Rohr, Journal of Applied Ecology 55, no. 6 (November 2018): 2876–87, https://doi.org/10.1111/1365-2664.13169. 15 Victorian State Government, ‘Great Ocean Road Action Plan’ (Victorian State Govern- ment, October 2018), https://www.planning.vic.gov.au/policy-and-strategy/great-ocean-road-action-plan. 16 Barwon Water, ‘Barwon Urban Water Strategy 2017’ (Barwon Water, March 2017), https://www.barwonwater.vic.gov.au/water-and-waste/urban-water-strategy. 17 Colac Otway Shire, ‘Colac Otway Planning Scheme’, cl. 35.06. 18 Colac Otway Shire, cl. 36.03. 19 Colac Otway Shire, cl. 44.04. 20 Colac Otway Shire, cl. 42.01. 21 Colac Otway Shire, cl. 42.03.