Sea Level Rise- The case of Byron Shire

SEA LEVEL RISE

The Case of Byron Shire

ARCH9092 Urban Report

13th November 2022

SID: 500629091

Abbreviations

SLR: Sea Level Rise

NSW: New South Wales

IPCC: The Intergovernmental Panel on Climate Change

ECPW: Emergency Coastal Protection Works

1.

3.

1. Introduction

This paper starts by explaining sea level rise (SLR) and its effects on the surrounding environment, as well as the risks it poses to the shoreline. In the Literature Review, the report will cover adaptation measures to mitigate sea level rise. Following this, a few principles will be found in the theoretical framework for the best practise to manage SLR on the coastline through a Literature Rreview, that  includes a discussion of the measures that can be employed to mitigate the effects of SLR. The study will analyse how these solutions compare to the existing strategies utilised by the Byron Shire Council to deal with the implications of SLR through the Results and Discussion chapters. The report’s conclusion will describe the study’s limitations as well as a possible future direction, and a proposal that will satisfy the report’s aim.

1. Introduction

1.1 What is Sea level rise?

Sea level rise (SLR) is the rise in water levels in the world’s oceans caused by global warming. As the oceans warm due to global warming, the water expands, causing sea levels to increase. Global warming and rising average temperatures are also forcing glaciers and ice sheets to melt at a faster rate than usual, resulting in an increase in ocean water levels. SLR is a global hazard to coastal life (National Geographic 2022).

The Intergovernmental Panel on Climate Change (IPCC) has predicted a 79 centimeter rise in sea level by 2100, putting coastal development at danger. Coastal areas are crucial ecological spaces because they serve to minimise erosion and pollution while also providing food, shelter, breeding areas, and nursing grounds for a diverse range of organisms. Coastal locations are important for enterprises because they give water space for shipping and ports, as well as recreational activities like fishing and diving plus raw resources like salt and sand. Many communities have residential sections along the coast. As water levels rise, it is critical to understand what will happen to all of these crucial sites along the coast. (Creel 2003).

SLR causes increasing storm surge intensity and floods that damage coastal regions. There are multiple metropolitan centres and huge populations located near coastlines, as well as a variety of coastal species that is vulnerable and threatened by SLR. It will have an impact further inland, polluting groundwater as saltwater seepage increases. This is an issue that requires close monitoring and coastal area preparation for the implications (National Geographic 2022).

1.2 Impacts of Sea Level Rise

SLR is a serious threat to the world since the bulk of the population lives near the shore and the infrastructure to support that population is also located near the coast. 60% of the world’s 39 metropolises with populations greater than 5 million are located within 100 kilometres of the coast (Fig. 1), including 12 of the world’s 16 cities with populations greater than 10 million (IPCC 2007). Living by the seaside increases the risk to life and property. Furthermore, in the last 20 years, there has been a growing trend of individuals flocking to the seaside. “According to Nicholls and Mimura (1998), 600 million people will live in coastal floodplain area below the flood level by 2100.” (Boateng 2008)

In addition to this coast being the most productive source, SLR will have an influence on the global economy and population. The following are the effects of SLR on the coastal zone (Boateng 2008):

• Inundation increasing (flooding) into the coastal land, can cause loss property and life.

• Frequent storm surges can cause destruction of the beaches and severe destruction and erosion of shoreline along with destruction of life and property close to the shore.

• Increased coastal erosion can lead to destruction of coastal properties and loss of life.

• SLR can cause reduction in water supply to towns, this will be caused by seawater intruding into the groundwater and fresh water sources.

• SLR will cause a change in estuaries and tidal river systems, destroying ecosystems and patterns of sedimentation

1.3 Australia’s Coastline

Australia is a coastal society, 85% of the population lives in coastal regions (Fig. 2), and the shore is extremely important - socially, economically, and environmentally. All of Australia’s state capital cities are located along the coast and are connected to networks for the nation’s exports and imports, as well as other commercial activity. Australians love the leisure afforded by the seashore, which is also a treasure trove of environmental assets that contribute to the importance of ecosystems (Department of Climate Change 2009).

Beaches, coral reefs, wetlands, estuaries, and low-lying places in Australia will all experience changes as a result of climate change. There is insufficient knowledge about the extent to which wetlands can aid in the flooding of low-lying areas for regional decision making (Department of Climate Change 2009).

If sea levels rise by 1.1 metres, about 40,800 to 62,400 residential properties in New South Wales will be inundated. The eastern coast of New South Wales experiences significant erosion and storm surges, as well as flooding into estuaries. Tropical cyclones have similar effects and flood low-lying agricultural regions and towns along NSW’s north-eastern coast (Department of Climate Change 2009).

Byron Shire is one such region on the north eastern coast of New South Wales. .

Fig. 1: Map showing populations living within 100km of the coast. (Source: Adapted from UNEP 2002, based on Burke et.al. 2001, Harrison and Pearce 2001)

1.4 The Case of Byron Shire

Byron Shire is also on the north-east coast of NSW and is prone to floods as a result of SLR. Rising sea levels are expected to have a huge impact on the Byron Shire, with hundreds of millions of dollars in property, industry, and assets at risk of submersion. Coastal and Biodiversity Coordinator Chloe Dowsett. (Byron Shire Council’s coastal and biodiversity coordinator) said the damage due to coastal erosion in the Byron Shire has been an issue since a long time (Hartley, 2022).

“Coastal hazards such as coastal erosion and shoreline recession, being the landward movement of the shoreline over time, appear to be occurring at a faster rate in Byron due to the complex nature of these processes and their interaction” said Ms Dowsett (Hartley, 2022).

In Byron Bay, coastal erosion is a common occurrence. The jetty was damaged and rebuilt in 1928 after being damaged by storm surge in the area. This jetty was rebuilt only to be destroyed by high seas in 1954 due to a tropical hurricane. The town has always strived to establish a balance between growth and natural land preservation. The management of the coastal zone has been the subject of ongoing controversy. Coastal preservation was predicated on long-term preventive measures for seal level rise under the previous government’s control (2005-2011) and invoked the policy of ‘planned retreat’ (Roche, et al. 2013).

In the 1970s, private owners built ad hoc sea walls with the cooperation of the council, using land fill and automobile wrecks. After tropical cyclone Pam caused beach erosion, resulting in the loss of numerous properties in Belongil, thus ‘planned retreat’ as a policy was adopted in 2004. In 2008, a revised act specified that private owners might deploy Emergency Coastal Protection Works (ECPW). This enabled landowners to secure their coastal properties using temporary shortterm ‘protection methods’. However, no attention was made to protecting the coast through more permanent engineering measures (Roche, et al. 2013).

Later built in 2015, the ‘coastal protection’ comprises of a major Groyne in the main beach and two smaller ones to the north and south. The structure was built of rocks of various sizes to defend the houses on the coast, but it also failed. As a result, Byron Shire requires improved protection techniques to manage the coastline while also considering the adjacent properties and community.

Fig. 3: The coast of a beach in Byron Bay has been significantly eroded. (Source: CNN 2020)

Fig. 2: The most densely populated area in Australia around the coast. (Source: Commonwealth of Australia 2019)

1.5 Research Problem

As Cooke et al. (2012) argue, “rising sea levels and increased coastal populations will place continuing pressure on beaches, and an integrated approach to managing the coastal zone is called for” (Roche, et al., 2013).

Research Aim

With the rise in Sea levels posing a threat, how can Byron Shires Coastal Management adapt to build resilience to impacts of increasing Sea Levels?

Objectives:

1. Adaptation policy options and strategies to address SLR

2. Planning for SLR on the coastline

(Source: 7News 2022)

Fig. 4: Famous Aussie tourist spots could ‘washed away’ by rising waters from climate change.

1.6 Methodology

This section describes the methodology used in this report in order to make it easier to understand. The case study will be introduced first, and then, based on the structure of the report, the methodology utilised in the report will be described in separate sections.

Byron Shire

Byron Shire is made up of national parks, residential and agricultural areas, as well as some industrial and commercial land usage. The majority of the urban areas are concentrated near the coast, particularly in Byron Bay. Rural area is primarily utilised for agriculture and farming. Tourism, like agriculture, is a major industry (id. Community, 2021).

Byron Shire is well-known for its gorgeous beaches and hinterlands, as well as its active community. It is one of the most frequently visited Local Government Areas. This topography provides residents and visitors with a distinct way of life. Byron shire’s population is expected to reach 37,950 by 2036 (Byron Shire Council, 2019). SLR is threatening the Byron Shire, causing coastal inundation and erosion, along with storm surges and sea level rise. The main beach and Belongil beach have already been subjected to coastal erosion. Since 1988, Belongil Beach has had annual coastal loss of 1.1+/- 0.3 meters (Byron Shire Council, 2019).

Adaptation strategies to SLR

The literature review includes three possible coastal adaptation strategies to sea-level rise, as endorsed by the IPCC (2001): protection, accommodation, and retreat. Secondary sources of information, such as reports, journal articles, and websites, were used to conduct this research. The literature study goes into greater detail about the various types of protective strategies for sea level rise. This is particularly thorough given that Byron Shire Council has a history of adopting protection techniques and is now assessing the best adaptation method to sea level rise via protection as a reaction to SLR.

Through this literature review three principles were established-

1. Reduces environmental damage

2. Can withstand external forces

3. Allows for community activities

Coastal Management Policies for SLR

The outcomes chapter describes the previous planning policies and techniques employed in Byron Shire, as well as future adaptation plans being developed to mitigate the effects of SLR. This chapter also investigates the effects of the tactics in use on the surrounding environment and community. This chapter’s information was taken from news articles, Byron shire policy documents, and reports.

Climate Change Adaptation Plan, Main Beach Shoreline Project Scope of Work, Climate Change

Strategic Planning Policy, Belongil Creek entrance opening strategy, Byron Shire Development Control Plan.

Assessment of Current Adaptation Strategy

The report’s discussion section covers the three principles and relates them to the current and planned planning strategy for mitigating the effects of SLR. The evaluation is based on qualitative research and how effectively the plan operates in relation to the three principles. It is difficult to evaluate adaption strategies using quantitative methods. Because quantitative approaches require a high level of scientific data and differ in terms of physical and climatic parameters from location to location. As a result, this report will employ the case study method with qualitative data.

2. Literature Review

People have traditionally been drawn to the shore because of its amenity values and access to resources along the water. Coasts include costs in addition to benefits, such as exposing properties and people to risks like storm surges. Climate change will enhance the dangers by increasing flooding, erosion, and permanently inundating low-lying coastal areas. SLR will have economic and human implications, but without adaptation, the damage caused by SLR will reduce global GDP by about 4%. (50 trillion USD annually) (OECD, 2019).

2. Literature Review

2.1 Climate Adaptation

SLR is different from current coastal change because there is no certainty around the pace of change and magnitude (OECD, 2019), and the time scale of change being long term, it creates low awareness regarding the coastal zone. There will be a long-time gap between when costs are made to reduce risks, and benefits are understood. Good investments for adaptation can prevent SLR (OECD, 2019).

McCulloch, et al (2002) has categorised a few climate adaptation strategies (Boateng, 2008):

1. Prevent the loss- Reduce vulnerability to climate change by adaptation strategies

2. Tolerate the loss- Do nothing to reduce the risks and danger, absorb the losses as they take place

3. Spread and share the loss- spread the costs over different populations.

4. Change the activity getting affected- substitute ongoing activities that can’t cope with climate change with other activities.

5. Considerations of land use- move the land use or activity to a safer location (Boateng, 2008).

Adaptation is a risk management strategy according to Easterling, et al (2004). They aren’t free of cost or fool proof, it is therefore suggested that the benefits of the actions must outweigh the value of costs in reference to adaptation strategies.

Adaptive strategies thus need to be compared and assessed and the best effective strategy can be identified to be implemented. The selection must also be based on the surrounding developments and ecology.

Biljsma et al. (1996) identified three possible coastal response options to sea-level rise, which were adopted by IPCC (2001) comprising: Protection; Accommodation; and Retreat.

2.2 The Protection Strategy

This policy aims to protect the land from the sea so that existing land uses can continue by constructing hard structures and implementing soft technical solutions. The main disadvantage is that they are frequently expensive and have limited or finite long-term performance, requiring regular maintenance to withstand extreme weather conditions. Despite the inadequacies of the protection strategy, it may still be the most appropriate adaptation for sea level rise, and it is dependent on the properties along the coast line, cultural heritage, nature, and society as contributing aspects of the shore line (Boateng 2008).

Protection of developed coasts is required if the cost of protection is less than the value of the properties and land threatened by SLR. If a coastline is undeveloped, it is more cost effective to allow natural SLR processes take over, but protection is required if SLR can lead to significant contamination of the area (Boateng 2008).

2.3 The Accommodation Strategy

This technique assumes that people will continue to live on the site but will alter their properties and activities. The policy includes: structural redesign (e.g., elevating buildings and strengthening foundations) to reduce the impact of flooding; zoning and proper land use policy to encourage only low capital investments on vulnerable lands; soft approaches such as dyke opening, wetland renewal, dune rehabilitation, and beach re-feeding to improve natural resilience; drainage modifications for built-up areas that may become inundated; and growing flood or salt-tolerant crops (Boateng 2008).

Accommodation for developed regions should be agreed upon if soft defences are capable of managing threats and providing the necessary level of protection to life and property. Accommodation as a technique could be excellent for impacted regions including agricultural land or eco-tourism land (Boateng 2008).

2.4 The Retreat Strategy

Retreat implies only a partial, or potentially no, effort to save the land from the sea. In the worstcase scenario, the coastal area is abandoned, allowing coastal landforms and ecosystems to migrate inland. This policy option is recommended for very vulnerable coastlines when the market cost and/ or technical complexity of securing the coast outweigh the benefits. To be effective, vulnerable people and infrastructure must be transferred away from high-risk areas (Boateng 2008).

This should be considered for developed lands only if the expense of protection exceeds the worth of the properties on that property. Retreat may be the best option for undeveloped land unless it is designated as agricultural land or is relatively limited, such as small islands that require conservation or have considerable ecological or commercial significance (Boateng 2008).

Fig. 5: Different adaptation strategies for communities in coastal areas prone to sea level rise (Source: Lotus Project 2021)

2.5 Different Kinds of Protection Strategies

Private landowners built rock walls to safeguard their property in the 1960s. They took only transitory and improvised measures. Byron Shire Council then implemented a policy of ’managed retreat’ to counteract sea level rise, which was a long-term approach that did not address the immediate effects or damage to property. The new government indicated that they will abandon the former policy of ‘managed retreat’ and the state-wide, to make it easier for landowners to defend their private property from minor storm occurrences using temporary ‘short-term protection’ methods such as sandbags (Roche, et al. 2013).

They subsequently opted to focus on present SLR hazards such as erosion and storm surges, as well as support local authorities and provide SLR guidance and information. These reforms resulted in a shift in policy from long-term to short-term strategies. Engineering solutions for the medium term were overlooked. Byron shire neglected to address further mediumterm protection options, despite the fact that the sandbags were just short-term solutions.

“The majority of solution’s considered above have overlooked well-established engineering choices, ‘hard’ and’soft’ solutions that can be employed alone or in combination.”

(Roche, et al. 2013)

Later in 2015, some rock walls and groynes were built as hard ‘protective measures’, although this wall failed during a year of high tides in Byron Bay (Roche, et al. 2013). The following are some various ‘protective techniques’ to consider while planning adaption strategies to be robust to the impact of sea level rise.

1. Temporary Protection

Sandbags of various lengths and widths can be used to offer temporary protection on sand beaches. Strong geotextile bags are quite inexpensive as they can be locally filled with beach sand (Scottish Natural Heritage 2019).

Buried sandbags can be an efficient and inexpensive last line of defence in areas prone to mild, seasonal erosion. They are useful for short-term (less than five years) headland protection while other options are designed and implemented, but they should be replaced by a longer-term solution. They have no positive long-term effects on the physical or ecological environment, other from the fact that they are transitory structures that can be simply removed (Scottish Natural Heritage 2019).

Sandbags that are exposed are unsightly and perhaps dangerous. They are ineffective at absorbing wave energy and may hasten local beach erosion. The fill material will leak from damaged bags and return to the beach, but the bags will linger as unsightly waste along the shoreline. Losses will be minimal if the fill material is locally sourced or equivalent to that found on the beach. Sandbags will impede the natural dynamic interchange of material between the beach and dune. They may also interfere with the natural landform and hinder longshore sand transmission. Overall, they cannot be employed as permanent solutions to deal with the effects of SLR and adequately safeguard the shoreline (Scottish Natural Heritage 2019).

2. Soft Protection

The majority of “soft” shore-protection approaches and technologies use natural materials. Beach nourishment, Reprofiling, and dune nourishment are examples of soft methods (Bennington-Castro 2017). The majority of a living shoreline’s footprint is made up of local components. Natural vegetation or other live, “soft” shoreline components such as oyster reefs, rock sills, or massive pieces of wood that are anchored for improved stability, either alone or in combination with stronger shoreline structure, are included.

Living shorelines provide ecological services, such as essential habitat, that promote coastal resilience by stabilising and minimising erosion (NOAA, 2020). Soft shore protection measures can lessen wave impact, slow down chronic erosion, and help reduce wave impact during a storm to some extent. Though soft protection alone will not defend you from a really high storm surge (12 feet) and must be combined with strong protection for the best results (Spiegel 2016).

Living shorelines provide good erosion protection and habitat for coastal species, which encourages its use as a stabilising aid along protected coastlines. Strong storms cause less damage to natural coastal habitats (such as marshes, dunes, mangroves, and coral reefs) than to reinforced shorelines. The abundance of fish and other living creatures important to shorebirds, as well as recreational and commercial uses, is greater in regions with natural coastal environment (NOAA, 2020). An important co-benefit of soft protection like beach nourishment and dune management, is that it retains beach and associated environments, as well as tourism (Everard et al., 2010; Hinkel et al., 2013; Stive et al., 2013; IPCC, n.d.).

3. Hard Protection

Hard engineering solutions involve the construction of artificial structures in an attempt to mitigate the effects of sea level rise on a coastline. Sea walls, rock armour, gabions, and groynes are some examples of this (Bennington-Castro 2017).

When waves collide with hard structures, the energy is reflected to nearby properties rather than dampened. Wave activity erodes the soil at the base, causing it to weaken and disintegrate. Hard protection also degrades the ecosystem and has a negative impact on sensitive coastal life. The wall reduces biodiversity by not providing any habitat. Hard tactics can be costly and require ongoing upkeep (Bennington-Castro 2017). Hard protection provides a high level of protection against violent storms. Hard protection can also provide public spaces such as promenades where people can enjoy the water (Bennington-Castro 2017). When the space is restricted, hard protection is an excellent solution. They can also be multifunctional, combining flood protection with roadways, parking lots, or seaside recreation areas (Stalenberg, 2013 ; van Loon-Steensma and Vellinga, 2014; IPCC, n.d.)

4. Hybrid Protection

Hybrid Protection use both structural and natural stabilisation solutions to make your shorelines more resilient. Bulkheads, geotextile fabrics, poly-mesh, filter socks, coconut fibre logs, and biologs are examples of hybrid approaches (Wiggins, 2018). If you wish to construct a firm coastline, protect the base of the shoreline (which is more prone to erosion), and shield the bank’s slope, hybrid solutions are recommended. A hybrid stabilisation strategy includes more artificial structural features than soft stabilisation solutions. Although hybrid constructions have a greater environmental impact on shorelines than soft shorelines and natural, undisturbed shorelines, they may provide some ecological benefits over hard structures. In coastline reaches with extensive hard shoreline armouring, hybrid structures are preferred over hard structures (Gianou, 2014).

Fig. 6: Gray and green infrastructure on the coastline (Source: NOAA 2016)

2.6 Theoretical Framework

Coastal management should be based on future projected occurrences and problems (climate change, sea-level rise, and their expected impacts on the coastal zone). The recommended solution for Byron Shire can be established by examining the existing methods in Byron Bay and the Protection Strategies. This is vital to know since understanding what strategy is best used at Byron Shire requires an understanding of what is already in place. The planning strategies studies are only for the coast to fight SLR. How do best practices for protection compare to existing strategies, as well as an assessment of adaptation policy alternatives and strategies to address the concerns (evaluating different adaptation and mitigation options), and the most effective and sustainable options for implementation in Byron Bay? This judgement is based on Byron Shire’s existing development conditions and natural coastline characteristics (Boateng 2008). Through the strategies written above 3 principles are identified that need to be met for a successful protection strategy for the coastline.

3 Key principles were identified

1. Reduces Environmental Damage

2. Can Withstand External Forces

3. Allows for Community Activities

1. Reduces Environmental Damage

One of the concepts is to reduce environmental harm since coasts have natural ecosystems and ecology that are vital to the environment and must be conserved in their natural state. Coastal processes are constantly dynamic and in flux; hence, working with natural processes rather than against them, and respecting them, will make our activities more environmentally sustainable and economically rewarding for a longer period of time (Mckenna & Cooper 2008).

2. Can Withstand External Forces

The rising sea level is causing coastal retreat, as well as water invading and eroding land features. When combined with storm surges, it can cause significant damage to life and property. As a result, the type of protection must be able to endure external forces for a longer period of time (Labuz 2015).

3. Allows for Community Activities

Many Australians love to spend their leisure time at the beach. Given its care for the coast, Australia may be expected to be at the forefront of coastal tourism development and coastal protection. SLR may have a substantial influence on tourism and recreation by affecting landscapes (e.g., beaches), cultural aspects (e.g., Marzeion and Levermann, 2014; Fang et al., 2016; IPCC, n.d.), and important transportation infrastructures such as ports and airports (Monioudi et al., 2018; IPCC, n.d.). As a result, it is critical to ensure that the coast is protected in a way that does not interfere with the region’s recreational activities.

3. Results

Byron Bay, located on the northern coast of New South Wales, is a notable erosion hotspot as a result of SLR. The modifications made and planned to the Coastal Protection Act in NSW are shown below. These reforms had a variety of effects on residents and local governments, resulting in disagreements in Byron Bay. Protection is one of the key adaptation policies now in use in Byron Shire for SLR.

3. Results

3.1 Coastal Management NSW

NSW coastal management adheres to the requirements established by the NSW Coastal Protection Act 1979, State Environment Planning Policy No. 71 - coastal protection (SEPP), and NSW Coastal policy (1997). Coastal design guidelines for NSW are another type of guidance that is employed (DP, 3003). Byron Shire voted in 2012 to commit to SLR planning and to modify the Climate Change Strategic Planning Policy 2009. The SLR included SLR standards of 0.4m and 0.9m rise in levels by 2050 and 2100(Fig. 7 and Fig. 8), respectively. A important strategy revised in the Coastal Zone Management Plan is the adoption of a risk-based approach to coastal management, which incorporates the uncertainties surrounding SLR and natural hazards and prioritises the adaptation of high-risk coastal zones (BMT WBM Pty Ltd 2013).

Fig. 8: Predicted inundation scenario in 2100 during high tide (Source: Coastal Risk 2022)

Fig. 7: Inundation scenario currently during high tide (Source: Coastal Risk 2022)

3.2 Past Policies for Byron Shire

Unstructured sea barriers were built by private owners with the support of the council in the 1970s, using ground fill and automobile wrecks, when tropical cyclone Pam caused coastal erosion, resulting in the loss of several dwellings Belongil. Following the cyclone, the Byron Shire Erosion Trust built coastal walls in 1975. The Byron Bay coast had been experiencing long-term sand erosion, with coastal protection activities being one of the principal reasons. Byron Shire council amended planning instruments in 1988, which indicated that coastal areas required to be either relocatable (planned retreat) or protected. This culminated in the adoption of planned retreat as a policy in 2004, which specified that any new developments or additions to existing ones in the coastal zone were subject to removal or relocation based on erosion and the distance approached from the coastal zone (Roche, et al. 2013).

The Byron Coastline Management Council discovered that the planned retreat framework was ineffective for urgent erosion risks or abrupt storm surges. The NSW government recognised the failure of long-term measures such as planned retreat in 2008, but was unable to deal with the immediate effects of SLR. As a result, a novel strategy was required (Gordon, Lord and Nielsen 2011 ; Roche, et al., 2013).

In 2008, a revised act specified that private owners might deploy Emergency Coastal Protection Works (ECPW). ECPW was made up of sand or cloth bags, but no rock or other debris. The issue was that the protection could only be put in place if directed by the Bureau of Meteorology and required approval from the local municipality. Furthermore, the building may only be put for a period of 12 months and extended only with approval. In 2011, the new liberal government suggested a variety of reforms to short-term policy, including making it easier for private owners to instal temporary works without further approval. Inform and educate the council about the effects of SLR and other factors. These strategies shifted from long-term planned retreat to short-term policies, but medium-term answers were disregarded (Roche, et al. 2013).

The labour government encouraged private owners to adopt ad hoc measures, but because private owners’ water fronts are shared with public amenities, it was only reasonable that the local government contribute to these protection works as well (Roche, et al. 2013).

3.3 Protection Strategies in Byron Shire

Following the planned retreat strategy and the ad hoc short-term protection policy, the council had the option of repairing and filling gaps in the existing structures established in the 1960s. This strategy will necessitate the replenishment of sand in areas where erosion has already occurred (Aparks 2015). Byron Bay is located in the centre of the coastal scenery. There is an existing coastal protection structure near the Byron Bay Surf Club that was built in the 1960s and 1970s, however it is dilapidated and in need of repair (Byron Shire Council 2022). A major Groyne guards the main beach, with two smaller ones in the north and south. The structure is composed of various sized rocks to defend the residences near the coast (Aparks 2015).

3.4 Effect of Proposed Protection Policies on the Surroundings

The rock wall that was constructed in 2015 (Fig. 9) failed in its first year due to high tides. And caused large amounts of sand erosion.

Cate Coorey from Byron Residents’ group stated that the:

“huge seas quickly stripped the sand that was covering the structure.”

“The rocks are exposed, the fabric that was holding it all together is in tatters and some of the rocks have been dislodged and are right down at the water’s edge,”

“We will lose the beach because sand in front of rock walls always, everywhere around the world, there are examples of it having disappeared.”

The rock wall is presently 100 metres long and will become part of the one-kilometer defensive construction envisaged by the council’s Cosatal zone management plan in the future (ABC North Coast 2016).

Wendy Tuckerman, Minister for Local Government, announced on June 6, 2022, that Byron Shire Council would receive $74,331 to finish its Coastal Management Plan (CMP). The CMP is a strategy designed to help the municipality manage Byron Bay, which is “one of the most popular and visited coastal locations.” (Wendy Tuckerman 2022).

This programme is the first step in assisting local governments in understanding the complicated coastal concerns and SLR. The program’s goals are to minimise the dangers of SLR, such as coastal erosion, and to restore wetlands and habitats (NSW Government 2022).

The council has the following objectives (December 2019) for the project that will be managed by Bluecoast consulting engineers (Bluecoast Consulting Engineers Pty Ltd., 2019).

1. To protect Byron Bay in an adequate manner against current and future coastal changes.

2. To reduce risks and take climate change into account (SLR)

3. To reduce the impact of the protection works on natural coastal processes.

4. Increase public safety

5. Improve the access to the coast and public amenities and recreational activities at Byron Bay.

Fig. 9: Byron Bay Coastline Hazards (Source: BMT WBM Pty Ltd 2013)

4. Discussion

Coastal management should be based on anticipated future and immediate occurrences and difficulties (climate change, sea-level rise, and their expected impacts on the coastal zone). Understanding the aforementioned existing strategies reveals that Byron Shire Council did not anticipate the immediate threats that the impacts of SLR can pose, instead focusing on the longterm effects of SLR (Byron Shire Council 2021).

4. Discussion

4.1 Sea Level Rise in Byron Shire

Throughout Australia, particularly the east coast, sea levels will continue to rise into the twentyfirst century. Byron Bay is at great risk of coastal erosion and floods as a result of SLR. Some sections of Byron have already experienced significant coastal erosion, such as Mainbeach and Belongil Beaches. Since 1988, the shoreline at Belongil Beach in Byron Shire has receded by 1.1-0.3 meters. These frequent occurrences will destroy the coast and make replenishment difficult. These consequences are exacerbated by rising sea levels (Byron Shire Council 2021). Some of these effects are as follows:

• Coastal erosion, shoreline retreat, and inundation

• Public safety at risk

• Infrastructure and utilities will be damaged

• Impact on tourism and recreational activities

• Damage to property

Byron Shire Council’s earlier approach of planned retreat did not account for the immediate effects of SLR. The latter strategies of protection through groynes, rock walls, and sandbags did not work as well as expected, as evidenced by the results, particularly when compared to the principles in the theoretical framework or the similar objectives set by the council for adaptative measures in the Coastal Management plan.

4.2 Reduces Environmental Damage

The existing approaches of rock walls and sand bags have not safeguarded the coastal ecosystem; in fact, storm surges have washed away sand and ruined the cover that was placed over the rocks to allow habitats to live and growas seen in Figure 10. Further it has caused an increased amount of sand erosion, not able to stabalise the sand. It is also vital to consider working with natural changes rather than working against nature in order to protect the coastal habitat (ABC North Coast, 2016). Soft shoreline protection measures provide ecological benefits, such as essential habitat, that promote coastal resilience by stabilising and minimising erosion (NOAA, 2020). Instead of destroying or opposing nature, this promotes it to grow stronger.

4.3 Can Withstand External Forces

The shoreline that will be affected by SLR includes more than 60 buildings and a railway line, thus protection that can endure external natural risks and forces is required to protect these structures (Carley, et al., 2016). To survive external factors such as hurricanes, the defensive approach must be adequately maintained. The rock wall built in Byron Bay in 2015 was completely destroyed in 2016 owing to high tides. Within a year, the rock had failed. It had no effect on sand erosion. The rock wall was damaged by this high tide, as the stones became loosened and washed up on the shore. This creates a dangerous environment. This demonstrates that the rock wall will be unable to endure abrupt extreme events on the coast line, such as storms (ABC North Coast, 2016).

4.4 Allows for Community Activities

Byron Bay is a well-known seaside town in Australia and a popular tourist destination. Tourism is an important aspect of the economy in Byron Bay, which is known for its beautiful beaches, suba diving, snorkelling, and surfing. The beach is also an essential part of the locals’ lives (The Editors of Encyclopaedia Britannica, 2018). As the beach is a part of everyday life in Byron, the preservation strategy should allow residents and visitors to access it on a daily basis. The current rock wall protection approach is haphazard and dangerous. Making the beach inaccessible.

“Everyone wants to have their beaches and if we allow sea walls to be built along all of these areas, we’ll end up with a whole series of sea walls and no beach.”

As stated by Professor Andrew Short, from the University of Sydney’s School of Geosciences. (ABC North Coast, 2016)

As a result, if any protective building does appear on the beach, it must be an useable space with services and recreational activities integrated into it (ABC North Coast, 2016). As a result, the suggested protective plan must satisfy all three objectives while protecting the citizens and properties of Byron Shire, keeping the beach accessible, and encouraging recreational activities when it is safe to do so.

Fig. 10: ‘Interim’ Beach wall built in 2015. (Source: Byron Residents’ Group)

5. Conclusion

To summarise, this report has primarily questioned  the prospect of rising sea levels, how can Byron Shires Coastal Management adapt to increase resilience to the effects of rising sea levels?

5. Conclusion

The report’s introduction addressed sea level rise and its effects, as well as the significance and effects it has had on Australian coasts including Byron Bay. In the Literature review, the report outlined the best methods that techniques might be applied for Byron Bay. Protective measures were examined in greater depth because Byron Shire has tried various protective strategies to manage the coastline and deal with the effects of sea level rise.

The report’s results section goes into detail on the existing policies and the effects they’ve had on people and the environment during and after major natural disasters on the coast. This demonstrates where and how the strategies failed. The discussions compared the existing strategies to the principles in the literature study and explained why the existing protective methods in Byron Bay failed and what principles must be met for a future solution to adapt to SLR and construct the Coastal Management plan for Sea level Rise. The adaptation policy alternatives given in this research are aimed at developing medium-term solutions that can successfully protect and be resilient to climate change-induced SLR in all aspects. In the Literature review, the protective solutions include hard protection, soft protection, temporary protection, and combined hard and soft protection.

In the past, Byron Shire tried hard protection using Groynes and interim protection through sandbags. Soft protection is a tough approach to implement because it is a beach with services and homes on site during high storm events. As a result, an integrated solution for the coastline is required.

Recommendation

Because soft shorelines cannot withstand harsher settings and very big storm surges, and hard protection can lead to more sand erosion and failure to sustain and grow natural ecosystems, additional methods of protection must be considered (Bennington-Castro, 2017). With regular maintenance, a novel option known as hybrid stabilisation can be considered a medium-term solution for 50 years.

When artificial structural elements are mixed with soft stabilisation approaches, hybrid stabilisation occurs. When compared to natural shoreline, hybrid buildings have a greater environmental impact. These hybrid buildings provide more ecological benefits than rigid protection and are useful in coastal areas with extensive development, such as Byron Bay. When soft shorelines are ineffective, these hybrid structures are prefered (Gianou, 2014).

Given the assets that exist around the coastal zone, it is vital to have a medium-term solution as well as a long-term solution of managed retreat when dealing with coastal zone management in Byron Bay. As a result, it is critical to develop a policy to deal with the immediate coastal hazards; however, it must be acknowledged that because SLR is a serious threat to the region, the coastline may have to be abandoned and may become impractical to protect over time; however, because the SLR benchmark is still 100 years away, the time is now to protect the coast and retreat from it when the threat becomes unmanageable.

Future Research and Limitations

A full study of Strategies for Byron Shire is required, notably through a cost benefit analysis for the region specific to the Byron Shire beaches. The protection strategies need to be detailed out and analysed for each section across Byron Shire and assess its impacts on the surrounds, the community and the environment.

Because some of the features are more scientific in nature, this report only covered the planning strategies with some design and infrastructure but did not handle it from an engineering standpoint.

Fig. 11: High tides and debris have inundated the main beach of Byron Bay, which has been closed to swimmers and surfers. (Source: Visontay 2020)

Fig. 12: Beach erosion Byron Bay. (Source: Hanson 2021)

6. References

ABC North Coast, 2016. Byron Bay divided by Belongil Beach rock wall plans. [Online]

Available at: https://www.abc.net.au/news/2016-06-07/beach-erosion-has-rock-walls-in-doubt-at-byron-bay/7486514#:~:text=The%20rock%20wall%2C%20which%20is,Government’s%20latest%20Coastal%20Management%20Bill.

[Accessed 2 November 2022].

Aparks, 2015. Byron coastal options include sand pumping, giant rock wall. [Online]

Available at: https://www.dailytelegraph.com.au/news/nsw/lismore/byron-coastal-options-include-sand-pumping-giantrock-wall/news-story/d554b2f372f85398e9a8a84c5f4d4cb7

[Accessed 18 august 2022].

Bennington-Castro, J., 2017. Walls Won’t Save Our Cities From Rising Seas. Here’s What Will. [Online]

Available at: https://www.nbcnews.com/mach/science/walls-won-t-save-our-cities-rising-seas-here-s-ncna786811 [Accessed 1 November 2022].

Bluecoast Consulting Engineers Pty Ltd., 2019. Design Investigation for the Modification of the Byron Bay Protection Works, Byron Shire: Byron Shire Council.

BMT WBM Pty Ltd , 2013. Byron Shire Coastline Hazrds Assesment Update 2013, Byron: Byron Shire Council.

Boateng, et. al., 2008. Integrating Sea-Level Rise Adaptation into Planning Policies in the Coastal Zone

Byron Shire Council, 2019. Byron Shire Draft Residential Strategy, Byron: Byron Shire Council.

Byron Shire Council, 2021. Byron Shire Council Climate Change Adaptation Plan, Byron Shire: Byron Shire Council.

Byron Shire Council, 2022. Main Beach Shoreline Project. [Online]

Available at: https://www.byron.nsw.gov.au/Services/Environment/Coast-and-waterways/Coastal-Projects/Main-BeachShoreline-Project

[Accessed 15 October 2022].

Carley, J. T. et al., 2016. Coastal Hazard Management Study - Byron Bay Embayment , Manly Vale: Water Research Laboratory (UNSW).

Creel, L., 2003. Ripple Effects: Population and Coastal Regions. [Online]

Available at: https://www.prb.org/resources/ripple-effects-population-and-coastal-regions/ [Accessed 10 August 2022].

Department of Climate Change, 2009. Department of Climate Change, Energy, the Environment and Water. [Online]

Available at: https://www.dcceew.gov.au/climate-change/policy/adaptation/publications/climate-change-risks-australias-coasts

[Accessed 10 August 2022].

Dupre, K. & Bosman, C., 2017. Development Versus Coastal Protection: The Gold Coast Case Study ( Australia ). Caribbean studies, p. 36.

Gianou, K., 2014. Soft Shoreline Stabilization , Washington: Washington State Department of Ecology.

Hartley, A., 2022. Coastal erosion damages Byron beaches. [Online]

Available at: https://junctionjournalism.com/2019/10/11/coastal-erosion-damages-byron-beaches/ [Accessed 15 September 2022].

id. Community, 2021. Byron Shire community profile. [Online]

Available at: https://profile.id.com.au/byron/about [Accessed 10 November 2022].

IPCC, n.d. Responding to Sea Level Rise, s.l.: IPCC.

Łabuz, T. A., 2015. Environmental Impacts—Coastal Erosion and Coastline Changes. Springer Open, pp. 381-396.

Mckenna, J. & Cooper, J. A. G., 2008. Working with natural processes: the challenge for coastal protection strategies. The Geogrophical Journal, 174(4), pp. 315-331.

National Geographic, 2022. Sea Level Rise. [Online]

Available at: https://education.nationalgeographic.org/resource/sea-level-rise [Accessed 04 September 2022].

NOAA, 2020. Living Shorelines. [Online]

Available at: https://www.habitatblueprint.noaa.gov/living-shorelines/ [Accessed 1 November 2022].

NSW Government, 2022. Next step for Byron Shire coastal management. [Online]

Available at: https://www.environment.nsw.gov.au/news/next-step-for-byron-shire-coastal-management [Accessed 15 October 2022].

OECD, 2019. Responding to Rising Seas- OECD Country Approaches to Tackling Coastal Risks, Paris: OECD.

Roche, K., Goodwin, I. & McAneney, J., 2013. Management of the Coastal Zone in Byron Bay: The Neglect of Medium-term Considerations. Agenda: A Journal of Policy Analysis and Reform, Vol 19(2), pp. 21-39.

Scottish Natural Heritage, 2019. Sand Bag Structures. [Online]

Available at: 2022 [Accessed 22 September 2022].

Spiegel, J. E., 2016. How to protect coasts from sea-level rise. [Online]

Available at: https://yaleclimateconnections.org/2016/07/as-sea-levels-rise-how-best-to-protect-our-coasts/ [Accessed 2 November 2022].

The Editors of Encyclopaedia Britannica, 2018. Byron Bay. [Online]

Available at: https://www.britannica.com/place/Byron-Bay [Accessed 05 November 2022].

Wiggins, J., 2018. 3 Ways to Stabilize Your Shoreline. [Online]

Available at: https://www.abbottsconstruction.com/3-ways-to-stabilize-your-shoreline/ [Accessed 25 October 2022].

6. Image References

Fig 1: UNEP 2002, based on Burke et.al. 2001, Harrison and Pearce 2001, Map showing populations living within 100km of the coast, Washington DC, viewed on 05 September 2022. https://www.grida.no/resources/5638

Fig. 2: Commonwealth of Australia 2019, The most densely populated area in Australia around the coast, viewed on 20 August 2022. https://www.9news.com.au/national/news-national-only-aussie-capital-city-with-a-declining-population-abs-update/6cab0be9-3def-45ee-9490-b9b7af7b9ead

Fig. 3: CNN 2020, The coast of a beach in Byron Bay has been significantly eroded, Byron Shire, viewed on 10 November 2022. https://edition.cnn.com/travel/article/byron-bay-weather-hnk-intl-scli/index.html

Fig. 4: 7News 2022, Famous Aussie tourist spots could ‘washed away’ by rising waters from climate change. Byron Shire, viewed on 20 September 2022 https://7news.com.au/news/wa/famous-wa-tourist-spots-could-washed-away-byrising-waters-from-climate-change-c-4027022

Fig. 5: Lotus Project 2021, Adaptive Measures for Increasing Sea Level Rise, Vietnam, viewed on 15 September 2022 https://www.lotus-project.org/blog/2021/8/26/adaptive-measures-for-increasing-sea-level-rise-in-vietnam

Fig. 6: NOAA 2016, Gray and green infrastructure on the coastline, viewed on 20 September 2022 https://yaleclimateconnections.org/2016/07/as-sea-levels-rise-how-best-to-protect-our-coasts/

Fig. 7: Coastal Risk 2022, Inundation scenario currently during high tide, Byron Shire, viewed on 10 August 2022 https://www.coastalrisk.com.au/viewer

Fig. 8: Coastal Risk 2022, Predicted inundation scenario in 2100 during high tide, viewed on 10 August 2022 https:// www.coastalrisk.com.au/viewer

Fig. 9: BMT WBM Pty Ltd 2013, Byron Bay Coastline Hazards, Byron shire, Byron Shire Coastline Hazards Assessment Update, viewed on 11 November 2022.

Fig 10: Byron Residents Group 2016, ‘Interim’ rock wall built in 2015, Byron Bay, viewed on October 1 2022. https:// byronresidentsgroup.org/rock-walls/

Fig. 11: Elias Visontay 2020, High tides and debris have inundated the main beach of Byron Bay, which has been closed to swimmers and surfers, Byron Bay, viewed on October 1 2022 https://www.theguardian.com/australia-news/2020/oct/20/a-lot-of-the-beach-is-gone-erosion-closes-byron-bays-main-beach

Fig. 12 : Steven Hanson, Beach erosion Byron Bay, Byron Bay, Viewed on 11 November 2022. https://www.echo.net. au/2021/10/byron-bay-main-beachs-future-tabled/