ISSUE 2, 2019 WATER LINES Resilience and Adaptation PlanningThe complexity of the challenges presented to us as a community in the face of climate change impacts, superimposed on our already variable climate, is now the subject of constant debate and discussion. At Water Technology, our core business has always been providing the tools and knowledge to, amongst the considerable uncertainty, provide clarity around what future climate scenarios might mean for our built environment and natural systems. We welcome, and in many areas are championing, the move to a more resilience- based approach to addressing these future challenges. Fragile systems will withstand stress to a point and break once that point is exceeded. Resilient (or robust) systems adapt in response to pressure to survive and grow. Across the country and internationally, we are increasingly using a resilience focus to enhance the adaptive capacities of our clients, our communities or systems within the coastal zone, our flood exposed rural and urban areas, implications for industry, waterway health and ecological impacts. STEVE CLARK Managing Director Welcome to our latest issue of Waterlines In this edition of Waterlines, we showcase several relevant resilience and adaptation planning projects that we have recently completed, including: • An erosion management plan for the Woodgate Beach shoreline; • The mapping and assessment of flora and fauna on the foreshore of Western Port Bay; and • Wetland management in a changing climate. Thank you for taking the time to read Waterlines. Please do not hesitate to contact me or any of the Water Technology team at any stage if we can be of assistance. 2 WATER LINES : ISSUE 2, 2019Building resilience and adapting to climate change requires a detailed understanding of a coastal community’s level of risk and the likelihood of impact. Coastal inundation assessments build an understanding of the likely impact of storm tide events. With much of the Port Phillip Bay coastline occupied by growing coastal communities, understanding the potential impacts of storm tide events and corresponding inundation is vital. Melbourne Water commissioned Water Technology to undertake a coastal inundation assessment of Port Phillip Bay. A comprehensive coastal inundation risk assessment was performed for Port Phillip Bay which combined a range of techniques, including the development of Port Phillip Bay storm risks. The assessment involved detailed historical extreme seawater levels (i.e. storm tide levels) and co-incident wind analysis across Port Phillip Bay. Additionally, hydrodynamic and wave modelling for present- day conditions and future climatic condition was undertaken particularly giving consideration to rising sea levels, providing a suite of realistic storm tide events. The mapping of maximum inundation extents for both present day and future climatic conditions enables Melbourne Water to plan for future sea-level rise and to provide information to local government and other decision-makers across the entire Port Phillip Bay region. The results demonstrated limited coastal inundation under existing water level conditions. However, the inundation extents increase significantly under a future sea-level rise condition. Key areas that were identified as being at risk of coastal inundation included Altona, Central Melbourne, Elwood and Kingston. Coastal erosion assessment and advice PORT PHILLIP BAY STORM TIDE MODELLING For more information, contact +61 3 8526 0800, Parvin Zavarei ( parvin.zavarei@watertech.com.au ) WATER LINES : ISSUE 2, 2019 3In 2015, the Australian Government released a National Climate Resilience and Adaptation Strategy which outlines the principles to realise the vision of a climate-resilient future: “We act together to support prosperity and wellbeing in Australia and beyond by building the resilience of communities, the economy and the environment to a variable and changing climate.” According to the strategy, resilience- building can encapsulate a wide range of actions, such as limiting or removing human pressures on natural systems (such as land clearing or pollution) or ensuring that vulnerable communities have reliable access to information and essential services. Resilience planning and natural hazard adaptation community-focused planning 4 WATER LINES : ISSUE 2, 2019Water Technology is involved in the preparation of a range of projects that help to develop strategies, action plans and solutions that enhance the resilience and adaptive capacity of communities and regions across Australia. When we talk about resilience, we include responses to long terms stresses as well as the disasters associated with extreme weather events such as floods, storms and bushfires. In Central Queensland, an investigation is already underway to understand the likely impacts of continually rising average temperatures in relation to the rural economy and community. In urban areas in Queensland, Victoria and Western Australia, Water Technology is undertaking multi-hazard resilience planning and developing best-practice flood warning systems as well as coastal hazard adaptation strategies. As we see global trends shift towards the adoption of resilience and adaptation measures, Water Technology provides the expertise to build capacity and capability to develop pathways to a more resilient future. There are a range of adaptation options that can be relevant for a community, and some may be more suited to specific areas relative to risk, expectation and feasibility. To gain community and stakeholder ownership, these options need to be discussed with stakeholders to help them understand future response options. While the options may be straightforward to describe, how this discussion is conducted is important given that options, such as retreat or do nothing in the case of coastal management, need to be canvassed and could fundamentally affect how the community and region functions in the future. Discussing these options with the community presents an opportunity to consider whether the options are required now, or in the future, which is a fundamental consideration for an adaptation pathways assessment. For more information, contact +61 7 3105 1460 Richard Sharp ( richard.sharp@watertech.com.au ) WATER LINES : ISSUE 2, 2019 5Shoreline Erosion Management WOODGATE BEACH The Bundaberg region has experienced several extreme weather events in recent years, and its coastal communities are vulnerable to impacts from coastal hazards such as coastal erosion and storm tide inundation. It is anticipated that the impacts of a changing climate will exacerbate these problems; local economies may be affected through disruption to business and social and cultural values and recreational opportunities may be affected. The 16 km Woodgate coast fronts onto the waters of Hervey Bay. This coastal reach is relatively stable over most of its length. However, significant changes are occurring at either end of the coastline due to changes in the extensive tidal deltas of Theodolite Creek and the Burrum River. The area around the existing boat ramp was identified to be the most at risk from erosion over the next 20 years. Community engagement highlighted the considerable lifestyle, recreational and environmental values afforded by the beach. Water Technology has prepared a Shoreline Erosion Management Plan to provide Bundaberg Regional Council with the necessary information to manage erosion of Woodgate Beach. Details of the natural processes that are shaping the foreshores of the Woodgate Coastal Reach were documented to enhance system understanding and thereby inform appropriate intervention decision making. Longshore and cross-shore sand transport and beach response modelling were conducted to quantify and determine the mechanisms of erosion at the site. A range of soft and hard management strategies were provided, along with the advantages, disadvantages and consequences of each. A combination of several strategies formed the recommended plan, and these were discussed with stakeholders in greater detail. This plan has provided a framework for the sustainable use, development and management of foreshores at risk of erosion along Woodgate Beach. It enables Bundaberg Regional Council and the local community to proactively plan for erosion management in these vulnerable areas in a way that is consistent with community aspirations and the policies of Queensland’s State Coastal Management Plan. For more information, contact +61 7 3105 1460 Richard Sharp (richard.sharp@watertech.com.au) Astrid Stuer (astrid.stuer@watertech.com.au) 6 WATER LINES : ISSUE 2, 2019Urban development has the potential to impact the environment through changed hydrological regimes and discharge pollution. Sensitive coastal zones, such as Ramsar listed wetlands, require additional environmental impact considerations to ensure protection. A flora and fauna assessment was undertaken along the Grantville foreshore on Western Port Bay, a Ramsar listed environment. This Melbourne Water project is part of a broader investigation to inform the choice of a drainage options for a proposed coatal development. Supporting studies and a high-level risk assessment were completed, supported by a detailed coastal hazard vulnerability assessment for the preferred option. The results of this project provided spatial identification of ecological values across the project area to assist in the selection of an option that avoids or at least minimises the impacts to the foreshore reserve. For more information, contact +61 3 5721 2650, Jamie Kaye ( jamie.kaye@watertech.com.au ) Johanna Slijkerman ( johanna.slijkerman@watertech.com.au ) Flora & Fauna Impact Assessment WESTERN PORT WATER LINES : ISSUE 2, 2019 7Wetland management in a changing climate Wimmera Wetlands and Lakes are highly valued for their recreation use and ecological significance. The influence of climate change and land use practice has the potential to impact receiving waters. Large wetlands and lakes within the Wimmera region have been impacted by infrequent inflows resulting in them not filling to historic levels. The Wimmera Catchment Management Authority sought to understand the changes and future impacts to the use of these systems as they are valued as recreational and tourism locations as well as being important ecological environments. A review of historic rainfall and water balance modelling was undertaken by Water Technology to produce water level predictions for historic conditions (assuming set stocking agricultural land use and pre- European catchment conditions), current conditions 8 WATER LINES : ISSUE 2, 2019climate and future climatic conditions (with decreased rainfall and increased evaporation). The assessment demonstrated to the community and government agencies the need to adjust their expectations of inflows to each wetland and to prepare their response to generally lower water levels. The continuing reduction in water levels and inflow frequencies in Lake Natimuk, St Marys Lake and Lake Wallace has the potential to change some of their values, with a reduction in recreational use and tourism potential. This reduction is already being felt in Natimuk with reductions in tourists visiting Lake Natimuk. Modelling showed a reasonable amount of water will still enter the wetlands, so they will still have modest volumes and water levels, but lower than in the past on average. Options to increase inflows to the wetlands could be considered such as modifying catchment areas or supplementing supply using pipeline water, sourced from an appropriate water entitlement. For more information, contact +61 3 8526 0800 Ben Hughes ( ben.hughes@watertech.com.au ) WATER LINES : ISSUE 2, 2019 9Next >