Lonsdale Bight: consultation, options and actions summary. December 2017

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1 Lonsdale Bight: consultation, options and actions summary

2 Contents 1. Lonsdale Bight Coastal Processes Project Conceptual frameworks applied to the project Review of investigations and studies Consultation activities Community open house and online survey Technical and agency response to community management suggestions Community workshop Workshop outcomes Moving forward Implementation of groyne/s Final comments from the land managers and asset owners Department of Environment, Land, Water and Planning Borough of Queenscliffe Parks Victoria... 8 Appendix I - Responses to technical feedback... 9 Appendix II - Open house summary flyer... 11

3 1. Lonsdale Bight Coastal Processes Project In July 2016, community members created the Save Pt Lonsdale Front Beach Facebook page to highlight concerns about low sand levels on Point Lonsdale front beach. To help inform community conversation about the issue, the Department of Environment, Land, Water and Planning (DELWP) commissioned an independent review of reports and investigations from the last 20 years which consider local coastal processes and sand management strategies. Agencies responsible for management of the foreshore of Point Lonsdale (Borough of Queenscliff - BoQ), Port Phillip Heads Marine National Park (Parks Victoria PV) and coastal protection structures (DELWP), came together to participate in sand management conversations with the community. The project enabled broad public conversation in sand management of the Point Lonsdale Bight. It included developing a shared understanding of the complexities of engineered and natural shorelines in a high wave energy environment, with competing environmental, economic and social values. This document summarises the project to date including reporting on community and agency discussions about sand management, and outlines options and actions going forward. 1.1 Conceptual frameworks applied to the project The project used Action Research principles to support the conversation between management agencies and community members. Action Research allows for new information to be brought into a research and decision making process during the research itself. This new information and understanding either emerges from within the process itself or because new information becomes available from other sources during the process. It is especially suited to situations that involve large numbers of people looking at complex problems. The process is based on cycles of Plan- Act Reflect - Refine, diagrammatically shown in Figure 1. Another conceptual model has also been employed to the project, commonly known as the Diverge - Converge model, shown in Figure 2. The project and this summary have been formed by an interplay of these two conceptual models. Plan Refine Act Reflect Figure 1. Conceptual framework for the cycle applied to this project. Figure 2. Diverge Converge conceptual model which applies to this project. 2 Lonsdale Bight:

4 1.2 Review of investigations and studies DELWP commissioned technical experts BMT WBM Pty Ltd (BMT WBM) to complete an independent review of reports and investigations of coastal processes and management strategies for Lonsdale Bight. The review considered 29 reports produced since 1997, with a focus on confirming coastal processes knowledge and identifying information gaps. The review included an overview of possible options for short and long-term sand management. Key points of the review are provided below. The full report and a summary fact sheet is available at What we know i. The Point Lonsdale front beach and marine environs is highly used with a wide range of environmental, economic and social values. ii. Protection structures are within the Port Phillip Heads Marine National Park; a state-wide significance for natural, cultural and tourism values. iii. A broad understanding of coastal processes in the Lonsdale Bight. This includes that: What we don t know sand supply around the Point Lonsdale headland and along the Bight is intermittent and variable depending on prevailing swell and wind conditions. It may also be subject to long-term decline associated with an evolving sand supply over geological time scales. beach lowering and erosion will occur under high wave conditions, particularly with elevated water levels and when sand is transported out of an area more quickly than it is supplied. there will be times when sand is transported offshore during storm events, lowering the beach until it returns. Even with new infrastructure, sand will still be transported offshore during storms. iv. What influences sand availability. For example: information on sand level fluctuations, including the extent and likely duration, and links to variations in coastal processes which cause this change. sand supply rates around Point Lonsdale and the associated variations in sand availability. v. What drives sand level change. For example: short to mid-term - near shore currents and the associated longshore sand transport, including variation throughout the year and over longer time periods. long-term the effect on sand levels under climate influences, including sea level increases and higher wave energy impacting on the engineered and natural shoreline. 2. Consultation activities 2.1 Community open house and online survey A community open house event was held at the Point Lonsdale Bowls Club on 18 January Approximately 400 people attended the two sessions to learn to about the review s outcomes. An online survey was held from January 12 to February , where 20 submission were received in response to the same questions posed at the open house. A flyer summarising feedback from the open house and online survey was provided to the community in March It can be found on the project website Lonsdale Bight: 3

5 2.2 Technical and agency response to community management suggestions Several management suggestions and technical statements were raised by the community during the open house and online survey. To consider these, the project s independent consultant, BMT WBM, reviewed and provided advice on the technical aspects of community feedback. This review was provided to participants at the workshops and is available in Appendix I. 2.3 Community workshop Two World Café style workshops were held on 17 May 2017 for community participants to further discuss key themes raised through the BMT WBM report and community open house on 18 January The themes discussed were: Monitoring Amenity and environment Structures (modifying and new) Sand nourishment and sand carting Safety A summary of consultation prior to the May workshops is available in Appendix II Workshop outcomes Thoughts, ideas and opinions were sought from workshop participants on each theme. This feedback was used to refine community preference for management options. The feedback is presented below, with advice and considerations from the BMT WBM report Monitoring Related workshop discussion theme: Monitoring Participants identified a need for more detailed monitoring at Point Lonsdale front beach. This supports the BMT WBM report recommendation for more data on sand transport within the Bight and along the foreshore, as well as detailed information on wave climate. More details on these knowledge gaps is provided in section 4 of the BMT WBM report. Participants expressed a desire to be involved in monitoring, regardless of future actions. A group could be set up to conduct monitoring. Any data collected could help inform any potential future projects. A separate issue was the need for the professional monitoring and research to fill knowledge gaps identified in the BMT WBM report Maintaining status quo Related workshop discussion theme: Amenity and environment, safety and monitoring During the workshop, participants confirmed they observe seasonal movement of sand at Point Lonsdale and that it does come and go. A variety of opinions were expressed, these include: questioning if there is a problem that requires any level of intervention/new infrastructure. monitoring seasonal variation in sand levels before any further works are considered. an acceptance of low sand levels during winter if sand was to come back over summer. a need for high sand levels to protect the wall and improve public safety. Overall, ongoing maintenance of the seawall, groynes and foreshore was highlighted as being the minimum level of management required at the site. It was acknowledged that the site s environmental values need to be maintained. 4 Lonsdale Bight:

6 The BMT WBM report (Section ) notes existing groynes provide some sand retention during low sand supply and that continued maintenance and do nothing /status quo is a valid short and long-term option Groyne field modification Related workshop discussion theme: Structures, amenity and environment, and safety A range of opinions were heard regarding introduction of new groynes at Point Lonsdale front beach. Feedback included whether new structures would impact on coastal processes, and how new infrastructure could create sandy beaches to attract visitors and support events such as the annual ocean swim and surfing competitions. While there was support for structures to be installed as soon as possible to increase sand levels, it was also acknowledged that more information was required to confirm economic benefits of sandy beaches and how this compared to the tourism appeal of a mix of reef and sandy beaches. Factoring low sand levels into event planning was also raised as an option. Some participants had safety concerns for the seawall with low sand levels, and for recreational beach users with more groynes. It was suggested new groynes would lead to a more even spread of the beach as well as protection to the wall. Among those that support groynes, there was an overall preference for wooden structures as they cost less, look better, take up less room on the beach and are effective. It was suggested a cost benefit analysis would be needed to accurately compare them to rock. There was support for a single trial groyne to test assumptions. There were also suggestions that current groynes should be modified/strengthened by replacing the existing rock with larger heavier rocks. Participants noted further monitoring is required to better understand seasonal variation and long-term trends before any new structures are installed. Section of the BMT WBM report discusses the historical presence of timber groynes and their functionality. Section of the BMT WBM reports outlines additional groynes as an option to retain sand at the front beach. It suggests two sites for consideration: south end of beach opposite shops and playground opposite Elizabeth Street The report highlights that the success of a groyne field is dependent on suitable sand supply, and that by their very nature of trapping sand, groynes transfer a sand loss further downdrift along the shoreline. These risks need to be assessed before any work is conducted Beach nourishment / localised redistribution of sand Related workshop discussion theme: Sand nourishment and carting, amenity and environment Participants at the workshop agreed sand nourishment would not be a suitable long-term solution. Those wanting sandy beaches indicated a preference for money and effort to be spent on longer-term solutions. Several participants indicated more information on costs and the process would increase understanding of the option of topping up beaches over summer. The BMT WBM report considers localised redistribution of sand (sand carting) and beach nourishment as short-term options in sections and respectively. The review highlights that if this option is used Lonsdale Bight: 5

7 sand carting may need to be continually repeated as and when needed, if its temporary benefits are considered effective Offshore breakwater Related workshop discussion theme: Structures, amenity and environment An offshore breakwater received little support from participants, however was not completely rejected. Some participants raised concerns about effects a breakwater might have on surfing at Point Lonsdale, as well as its effectiveness. As this option was not a preference of those at the workshop or in broader consultation, is not discussed further in this summary as a possible option. An offshore breakwater is discussed as a long-term solution in section of the BMT WBM report. If properly designed, constructed and maintained, the review advises offshore breakwaters could provide longterm benefits for sand retention, however they would be costly and result in significant impacts on the Port Phillip Heads Marine National Park, surfing and visual amenity. 3. Moving forward Based on outcomes of the BMT WBM report and community consultation, the below table summarises community responses throughout the consultation to management options. BMT WBM report management option Monitoring Consultation outcomes General support for sand monitoring within the Lonsdale Bight. Citizen science monitoring: Actions There are various initiatives for citizen coastal monitoring and reporting programs. If a group or individual is interested in being a part of a monitoring group, they can contact the Borough of Queenscliffe Customer Service on: to express interest. Maintain status quo Ongoing maintenance of the seawall, groynes and foreshore is a minimum level of management required at the site. Coastal Monitoring Guidelines for Sandy Beaches workshop: A workshop about coastal monitoring (why, where and how) is being planned. An invitation to attend will be sent to those who provided their contact details with the project. The workshop will also be advertised through local community networks. Maintenance of seawall: DELWP is responsible for coastal protection assets, and is committed to maintaining the seawall at Point Lonsdale front beach and the existing groynes. This includes regular inspections and maintenance to ensure they remain safe. Maintenance is funded through DELWP s coastal protection infrastructure and upgrade program (CPIUP) where funds are allocated on a risk basis across the region and state. Technical advice confirms the integrity of the current seawall, including its foundations, with low sand levels. Maintenance of existing rock groynes: DELWP continues to maintain existing rock groynes to ensure they remain safe, including repairs after storm events. 6 Lonsdale Bight:

8 Maintain status quo continued Maintenance of foreshore: The Borough of Queenscliffe continues to maintain the foreshore and ensure that it is safe for public use. Groyne field modification Many in the community support the addition of more groynes at Point Lonsdale front beach, however, many also expressed safety concerns. DELWP investment into new structures is based on risk and co-investment along with relevant technical investigations, cost benefit analysis, community support and obtained approvals (as described in Section 4 below). Preserve and Protect Port Phillip Heads Marine National Park values: Parks Victoria continues to manage the Port Phillip Heads Marine National Park, consistent with the objectives of the National Parks Act 1975 and the park management plan. Under the National Parks Act 1975, Ministerial or delegate approval is required for any new structures in the Port Phillip Heads Marine National Park. Installation of additional groyne(s): south end of beach opposite shops and playground Additional groynes at this site require further research to inform design as outlined in the BMT WBM review (pg. 60) - The higher wave energy and different alignment of the shoreline means the behaviour of newly constructed groynes in this area is likely to be different to the existing groynes. Design of any works in this area would therefore require further investigation to inform the concept and detailed design. An investigation would inform the concept proposal and design of groynes, as well as assist Parks Victoria approval considerations. and / or opposite Elizabeth Street (BMT WBM review pg. 61) Further research is not required at this site to assess the environmental conditions. As stated in BMT WBM review (pg. 60), groynes at this location could be expected to behave in a similar fashion to the existing structures and therefore information gleaned from their historical behaviour could be used to inform design. Like maintenance, DELWP investment into new coastal protection infrastructure is achieved through DELWP s CPIUP program where funds are allocated on a risk basis and are competitive against other risks in the region and the state. 4. Implementation of groyne/s There must be community and government support for the construction of groynes, including any trial structures. This includes all relevant approvals, such as planning permits, consent under the Coastal Management Act 1995 and approval from the Minister under the National Parks Act 1975 for any works in the Port Phillip Heads Marine National Park. These approvals will require an assessment of the impact of any proposed structure on biodiversity, of the park, both inshore and offshore habitats. As mentioned in Section 3, DELWP investment into new coastal protection infrastructure is based on a standard risk-based approach and funded by the Coastal Protection Infrastructure and Upgrade Program (CPIUP). There are no current public safety issues or immediate risk to assets due to sand fluctuations at Point Lonsdale. While funds from the CPIUP will be directed to manage risks at other locations, maintenance of the Point Lonsdale seawall and groynes will continue as needed. Other government funding programs that may invest in infrastructure on coastal Crown land include the Public Access and Safety Along Victoria s Coast Program, which addresses risks to public safety on coastal land; and the Port Phillip Bay Fund, which supports community groups and organisations to protect and preserve the environmental health of the bay. The government is willing to consider alternate funding models where a group or organisation has achieved community and land manager support. Lonsdale Bight: 7

9 5. Final comments from the land managers and asset owners 5.1 Department of Environment, Land, Water and Planning Sand management is a complex issue, particularly within a high energy engineered environment such as Point Lonsdale and much of the Lonsdale Bight. With no public safety nor asset at immediate risk, the likelihood for priority funding from DELWP s Coastal Protection Infrastructure and Upgrade Program to fund new groynes is low. While social and economic values are important considerations to DELWP at this location, the hierarchy of principles for coastal management in Victoria, set out in the Victorian Coastal Strategy 2014 (VCS) 1, directs decision making and prioritises protecting significant environmental and cultural values. As the area is within a declared Marine National Park, these values must be weighted above others. Should the community and/or other agencies prioritise maintaining consistent sand on Point Lonsdale front beaches, and provides supporting rationale, DELWP would guide them through the statutory approvals process. 5.2 Borough of Queenscliffe Council is the appointed land manager of crown land at this location and as such plays a stewardship role on behalf of the community for most of the foreshore land in the area and the landside infrastructure and assets. The increasing visitor appeal of this location also means an increasing role for Council in terms of upgrade, maintenance and upkeep of foreshore infrastructure and facilities, particularly those that facilitate access to the beach. The level of beach sand is recognised as a feature of the community living and visitor experience however Council also recognises the very dynamic nature of this coastline. Council supports a more formal approach to beach sand monitoring arrangements to further understand this process and will work with the community on establishing a monitoring program. Council will also continue to work with the community and other agencies to look at opportunities to improve the level of beach sand into the future subject to funding availability. 5.3 Parks Victoria The Point Lonsdale front beach has a long history of constant change. With its inclusion in the Port Phillip Heads Marine National Park in November 2002, greater attention now needs to be given to balancing longterm visitor use and enjoyment of the foreshore within the park with the significant environmental values of the Lonsdale Bight, including the impacts of near shore developments on the offshore reefs. Critical assessment of any development or upgrade options will need to be undertaken to ensure that the benefits to both the community and the environment are clear and long-lasting. 1. The Victorian Coastal Strategy, 2014 (VCS), governments key coastal policy, documents the hierarchy of principles which guides decision making on the coast. The starting point is recognising and protecting significant environmental and cultural values; followed by undertaking integrated planning and providing clear direction for the future; ensuring the sustainable use of natural coastal resources; and when the above principles have been considered and addressed, ensuring development on the coast is located within existing and modified and resilient environments were the demand for development is evident and any impacts can be managed sustainably. 8 Lonsdale Bight:

10 Appendix I - Responses to technical feedback During the open house, several technical concerns and suggestions were made by community members. The following is a table of responses that address these. New structures Option Response Build groynes with gaps along its length. Having groynes with gaps in them allow water to flow through, but also allows sand to flow through. This limits the capacity for the groyne to trap sand. Return to using timber groynes The reports reviewed indicated timber groynes are more prone to damage and deterioration, resulting in higher ongoing repair and replacement costs. This makes them less effective at retaining sand on the beach. From a cost / benefit viewpoint coastal managers have generally moved away from timber groynes in dynamic coastal locations where rates of damage / deterioration are higher. Add more groynes to improve their effectiveness While the existing groynes are effective in retaining sand, their spacing in relation to their length and height is not optimal under low sand supply conditions with sections of low beach levels in between. However, it is complex. If natural supply is limited, artificial beach nourishment may need to be considered to provide the required sand. It should also be noted that risk of sand being transported offshore during storm events remains even with a larger number of groynes. This erosion can occur quickly with the return of sand likely to be gradual over a much longer time frame. A better understanding of the variability in sand supply will help determine appropriate spacing of the groynes. Based on current knowledge, groyne spacing less than that between the existing southern and central groynes would be more likely to retain sand. Channel deepening Option Channel deepening has contributed to the loss of sand Response No long-term monitoring is available on wave climate or sediment supply within the immediate Lonsdale Bight. The Office of the Environmental Monitor (OEM), established to oversee the impacts of the channel deepening project, gave the bay a clean bill of health in its final report. The reports of the OEM are publicly available. Lonsdale Bight: 9

11 Modify structures Option Response Make groynes wider Make groynes longer Make groynes higher Use bigger rocks when rebuilding groynes A groyne s width is usually informed by its height, the width at the top and side slopes. The higher the groyne, the wider its base. Reports indicate the width of the groyne does not have a major influence on the wave and sand build-up patterns, unless it is substantial (such as an artificial headland). A longer groyne will trap more sand and retain a wider/longer beach. However, the low height of the existing groynes allows sand and water to go over the top which negates the effect of the length. The original design and construction of the hybrid rock/timber groynes meant waves pushed and built up sand to ultimately spill over the top of the seawall behind. This added to maintenance issues for the path. Reports also indicated the original two groynes were cut down in height to reduce the sand build up over the seawall and maintenance issues on the promenade. Existing groynes have been built from various materials, including a hybrid rock/timber design for the northern and southern groynes. After the southern groyne was damaged, the hybrid design was abandoned in favour of rock for the construction of the middle groyne. Construction of any future groynes will need to take relevant design criteria into consideration. Create gaps between the wall and the groynes for pedestrian access Use sand to improve the integrity of the seawall and reduce impact of overtopping from waves. Groynes with a gap at the seawall end will allow water and some sand to flow through. However, the existing groynes have been modified to be low, and this allows waves and sand to spill over them, hindering the ability to retain sand. DELWP continues regular assessment and maintenance to ensure the seawall s stability and integrity and increase its functional life. Recent inspections with maritime engineers confirmed the foundations were in good condition. Coastal engineers indicate, and recommend, ongoing maintenance is typically required for seawalls in dynamic coastal locations. Sand in front of the see wall would see a reduction in the energy of wave interacting with the wall. However, its integrity is not solely dependent on the level of sand. Overtopping of the seawall occurs in high swell events and will occur more frequently in all climate change scenarios (higher sea levels; more frequent storms) 10 Lonsdale Bight:

12 Appendix II - Open house summary flyer The below flyer is also available on the project website - Lonsdale Bight: 11

13 12 Lonsdale Bight: