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- Cyclone Alfred & Coastal Resilience: ICM Coastal Experts in the Media
Cyclone Alfred put the Gold Coast’s coastal resilience system to the test, sparking widespread media discussion on beach erosion, recovery timelines, and coastal resilience. Over the past week, ICM’s coastal engineers have been featured on major TV, radio, and digital media outlets, providing expert insights into how the coastline is responding. From Channel 7’s Sunrise to ABC News and national radio, ICM's Angus Jackson and Aaron Salyer explained why erosion is a natural process, how our engineered systems are protecting valuable infrastructure, and what’s next for beach recovery. Below, we’ve compiled key takeaways, expert quotes, and highlights from our media appearances. Channel 9 News TV Interview, 8 March 2025 | Angus Jackson joined Channel 9 News to discuss the impact of Cyclone Alfred on the Gold Coast's beaches and how the city’s coastal resilience strategies have performed under extreme conditions. Alison Ariotti, Channel 9 News: "What is the process for people at home to understand that the beaches need to go through to fix this erosion?" "What normally happens is an event like this is Council closes the access ways to the beach, which they've done to try and stop people getting onto the beach, and not being able to get off, because at high tide, there is no beach. There's vertical scarps with waves hitting them, and we've all seen that on TV over the last few days. Council generally then comes along and and knocks the scarps down to make them safe." - Angus Jackson, International Coastal Management 4BC with Gary Hardgrave Radio Interview, 11 March 2025 | Aaron Salyer joined Gary Hardgrave on 4BC Radio to discuss the Gold Coast Mayor’s plan to restore the beaches and how coastal infrastructure played a crucial role in limiting storm damage. Gary Hardgrave, 4BC: " I know they put rock walls and groins in certain spots, that's to stop some of the prevailing currents moving sand up and down the coast. Some beaches get fuller at the expense of others and so forth. Is there any other solution that we can do or this is just it, you get a big cyclone, it's going to suck the sand out, you got to pump it back or wait for it to come back over a period of time." "There is, but there's a couple of good points you made. So under the sand dunes along the Gold Coast, pretty much for the majority of the stretch, there's a buried rock wall ( terminal seawall ). So that was put in after those cyclonic events of the 60s and 70s where, houses were falling in, and roads were falling into the sea." "So it really creates that, that sort of last backstop, for worst case events like this one. Thankfully for the majority of the Gold Coast, dunes are built in front/on top of that rock wall, which are actually artificial dunes , or 'urban dunes', so they're put there by design to create this natural buffer between the sea and that submerged rock wall. Most of the Gold Coast hasn't even exposed that worst case scenario rock wall buried under the dunes. So, for the most part the dune system really is doing its job and actually acting as a natural buffer, because what we don't see all the way up and down the Gold Coast are properties and roads falling into the sea." - Aaron Salyer, International Coastal Management ABC Drive with Bern Young Radio Interview, 11 March 2025 | Angus Jackson sat down with Bern Young on ABC Gold Coast Drive to share a historical perspective on coastal engineering and how past cyclones shaped today’s Gold Coast resilience strategies. Bern Young, ABC Gold Coast: "My guest is Angus Jackson. Now he's an executive coastal engineer with International Coastal Management, his own company after being Council's coastal engineer for a very long time, and a very important time in Council's history. Some people call you the godfather of the coastal protection system that we have. And this includes things like bypassing, backpassing , dune restoration , what we've seen with the sand pumping to create the super bank at one end, world leader in artificial reefs . [...] And he reckons the beaches have well and truly passed a major stress test. with Alfred." "The beaches are in great condition and that's not by luck. That's by good engineering. We lost our beaches in the 67 event and it took a long time to get them back. In fact, in 1967, the Gold Coast nearly went bankrupt because our beaches disappeared. That left a legacy in our DNA - we were never going to let that happen again. Today, we have seawalls , artificial reefs , and an entire system designed for events like this." - Angus Jackson, International Coastal Management Channel 7's Sunrise TV Interview, 12 March 2025 | Aaron Salyer joined Matt Shirvington and Natalie Barr on Channel 7's Sunrise to explain the science behind beach erosion and how the Gold Coast is planning for a faster recovery. Matt Shirvington, Sunrise : " What about the sand? Because so much of it has been basically washed back into the ocean. How do we get it back on the beaches?" "The way these beach systems work is they're quite highly dynamic. Erosion is actually a natural process. So the dune systems up on the top of the beach get hit by high impact storms. Some of that sand goes out into the offshore zone, which create those offshore sandbars. Now those offshore sandbars over time will naturally start to wash back in and rebuild this naturally." "That could be over, the course of a matter of months. It could even be, up to a couple of years to fully recover. But here on the Gold Coast, we just can't wait that long. We're too dependent on this beach, not only as a soft infrastructure, but as an asset. To the community. So the Gold Coast Council is going to step in hurry that along by doing things like bringing in a big dredge to actually shift that sand from offshore onto the onshore zone." - Aaron Salyer, International Coastal Management Sydney 2SM with Chris Smith Radio Interview, 13 March 2025 | Angus Jackson joined Chris Smith on Sydney’s 2SM Radio to discuss where the sand has gone - and how Gold Coast’s innovative sand management policies ensure beach recovery. "We've got policies in place, so any dredging in the broadwater, that sand goes to the beach. The Gold Coast beaches are incredibly managed. So at the moment, we pump sand across from the Tweed River from New South Wales into Queensland." "And then that sand travels along the Gold Coast and at the northern end, at the seaway, the Nerang River, sands pump northwards to continue its route. Times like this they turn on the tap and they pump back south to surfers paradise. So once that pipeline has been restored, there'll be a recirculation of sand." - Angus Jackson, International Coastal Management Channel 7's Sunrise with Sam Mac TV Interview, 14 March 2025 | Aaron Salyer joined Sam Mac on Channel 7's Sunrise to check in on how the Gold Coast beaches were holding up post-cyclone. Sam Mac, Sunrise: "We wanted to check in on the Gold Coast. Of course there's been lots of discussion and lots of pictures floating around vision of the scarping that's been happening. As you can see, it's a, it's around a three metre drop. [...] This must be the busiest time in your life." "Yeah, absolutely. But to me, this isn't as bad as it looks. For most people when they see this, they go start freaking out. But for me, I look at this and I go It's not so much about what was lost, it's about what wasn't lost. Look behind us. All of the buildings are intact, all the roads are there. The beach is doing its job, it's taking the brunt of the force of that cyclone." - Aaron Salyer, International Coastal Management ABC News with Nate Byrne TV Interview, 14 March 2025 | Aaron Salyer joined Nate Byrne on ABC News Breakfast to explain how Gold Coast beaches are designed to recover after extreme weather events. Nate Byrne, ABC News Breakfast: " Okay, first of all, talk to me about what's happened here. Courtesy of Alfred. There must be just I can't even fathom the volume of sand that's missing." "Yes. Millions of cubic meters of sand have been eroded from the beach. But erosion is a natural process. Erosion happens at all kinds of times. But, in these kind of extreme events big wave energy hits the top of the dunes, takes out that sand and actually takes it offshore into the sort of offshore zone, which creates those offshore sandbars. What happens then is that naturally breaks the wave energy. And over time, those sandbars will actually start moving back in." "So this is a natural process. What's exciting for me as a coastal engineer is to see that, we had 12 metre waves out here just a few days ago and it's only eroded, slightly, not even all the way back to the worst case scenario here. The Gold Coast has been really prepping for this moment for decades." - Aaron Salyer, International Coastal Management ABC Gold Coast Mornings with Sarah Cumming TV Interview, 14 March 2025 | Angus Jackson joined Sarah Cumming on ABC Gold Coast Mornings to explain the science behind sand dredging and beach nourishment . Sarah Cumming, ABC: " Tell us about how these sand dredging barges actually work. They don't actually take the sand from the ocean and dump it on the shore. They just move it back into the surf zone. Is that right? Can you just explain how that works for us?" "Yes, so when we were doing this back in the 1980s, we had no beaches at the southern end of the Gold Coast - just boulder walls. We needed to nourish those beaches very quickly. We were researching storm bars, which naturally move back onshore after a storm event, and we quickly recognised that if we created artificial storm bars with a dredge, nature would do the rest within six to 12 months - at about half the cost of traditional methods." "In 2017, the Gold Coast’s last major nearshore nourishment project moved around 3 million cubic metres of sand offshore. The dredge goes out, finds a good sand source, brings it in, and if it’s a really big dredge, they ‘rainbow’ it - pumping the sand into the air so it lands in the surf zone, where waves naturally bring it up the beach." "This method, developed by the Gold Coast City Council in 1985 when I was in charge, is now used globally. The benefit is that we don’t need pipelines on the beach - everything happens in the surf zone. And in 2017, we even designed the placement to improve the surfing conditions, so it’s a really nifty method." - Angus Jackson, International Coastal Management The Gold Coast Stress Test Cyclone Alfred provided a real-world stress test of the Gold Coast’s coastal resilience framework. The engineered dune systems , seawalls , and sand bypassing measures all performed as designed, preventing major infrastructure loss and setting the coastline up for a faster recovery. At International Coastal Management (ICM), we remain at the forefront of coastal engineering solutions, working with cities and communities worldwide to develop sustainable, nature-based resilience strategies.
- Seawalls in Australia: What you need to know
Australia's diverse coastlines are subject to constant change due to natural processes and human activity. From erosion to rising sea levels, protecting coastal properties has become a critical concern for homeowners, developers, and businesses. Building seawalls in Australia can be part of the solution, however they are just one piece of the puzzle in coastal resilience puzzle. At International Coastal Management (ICM) , we specialise in guiding property owners, councils and developers through the complexities of coastal protection. From navigating local regulations to designing and implementing tailored solutions, we ensure your coastline is protected while balancing environmental sustainability. Understanding Coastal Protection in Australia Coastal protection projects in Australia often require rigorous approvals and compliance with strict regulations. If your property or development falls within a coastal protection (erosion-prone) overlay, councils may request an engineering report certified by a Registered Professional Engineer with coastal engineering experience - even if erosion risk is deemed minimal. How ICM Helps You Navigate Coastal Protection At ICM, we understand the complexities of coastal approvals and work closely with property owners, developers, and councils to ensure compliance. Our services include: Regulatory Guidance: Interpreting and addressing council requirements under coastal protection overlays, planning schemes, and erosion risk assessments. Permit Applications & Compliance Reports: Preparing engineering reports, RPEQ-certified assessments, and design justifications that satisfy council and regulatory requirements. Seawall & Coastal Structure Design: Providing tailored solutions for seawalls, revetments, dunes, and nature-based coastal defences that enhance resilience. Construction and Monitoring: Overseeing project implementation and ensuring long-term success. With decades of experience in seawall design, approvals, and compliance across Australia’s coastline, ICM , an experienced coastal engineering company , ensures your project meets all necessary regulations efficiently and cost-effectively. Need an RPEQ Certified Coastal Engineering Report? If your council has requested an RPEQ certified report for your seawall or coastal development project, we can help. Our team includes RPEQ-certified and Chartered Engineers with extensive experience in coastal hazard assessments, seawall design, and erosion risk mitigation. We provide comprehensive reports that meet council requirements, ensuring your project gains the necessary approvals while delivering long-term resilience. Contact us today for expert guidance and tailored engineering solutions. Are Seawalls the Right Solution? Seawalls are one method for protecting properties from erosion and wave action. Typically constructed from boulders, concrete, or other durable materials, they serve as a barrier to safeguard beachfront infrastructure. However, seawalls alone may not address the root causes of coastal erosion, and they come with their own set of advantages and disadvantages . At ICM, we approach coastal protection holistically, considering all three elements of the Coastal Resilience Framework : Top of Beach : Managing dunes and vegetation to stabilise the shoreline. Bottom of Beach : Enhancing nearshore zones to dissipate wave energy. Sediment Supply : Ensuring a balanced flow of sand to sustain beach health. By evaluating these factors, we ensure that a seawall in Australia is part of an integrated solution tailored to the specific needs of your site. Types of Seawalls Seawalls come in a variety of forms, with their design tailored to the specific needs of the coastline they protect. Materials can range from rock and boulders , which provide a natural and cost-effective barrier, to concrete and modular designs , often used for their durability and adaptability. Living seawalls are an innovative option, incorporating features that can support marine life habitat while offering coastal protection. Geotextile container seawalls , made from durable fabric filled with sand or other materials, are a flexible alternative suitable for temporary or less-impacted areas. Seawalls also differ in shape, influencing their effectiveness and interaction with wave energy. Sloped seawalls dissipate wave energy gradually, reducing impact forces, while vertical walls reflect wave energy but may increase turbulence. Curved or stepped seawalls are designed to deflect waves upward or break their energy in stages, offering additional protection while potentially enhancing aesthetics. The choice of seawall type depends on site-specific conditions, including wave dynamics, environmental considerations, and budgetary constraints. Enhancing Seawalls with Dunes and Living Elements In many cases, seawalls work best when combined with other coastal resilience measures. For example, Gold Coast seawalls incorporate vegetated dunes on top of them, to provide an additional layer of protection by helping to trap sand, reduce wind erosion, and absorb wave energy. Similarly, living elements like oyster reefs or seagrass beds can enhance biodiversity while contributing to coastal stability. Our team at ICM designs solutions that work with natural processes, creating sustainable outcomes that benefit both communities and the environment. When to Consider Coastal Protection If you're noticing signs of erosion or instability on your property, it’s crucial to act quickly. Warning signs include: Retreating shorelines. Visible cracks or damage to existing seawalls. Increased exposure of dunes or vegetation to wave action. Accelerated loss of beach sand. Early intervention can save significant costs and prevent further damage. Contact ICM for a site-specific analysis and recommendations for your project. Building Coastal Resilience for the Future Protecting Australia's coastlines requires more than just hard structures like seawalls. By integrating solutions that address the top of the beach, bottom of the beach, and sediment supply, we create systems that are adaptive, sustainable, and resilient. At ICM, we believe in working with natural processes to protect your property while preserving the beauty and biodiversity of Australia's iconic coastlines. Ready to Protect Your Coastal Property? Whether you're a private homeowner or a developer, coastal protection can feel overwhelming. ICM is here to simplify the process and deliver results you can trust. Contact us today to discuss your coastal challenges and explore tailored solutions for your property.
- Building Artificial Surf Reefs: Worldwide Lessons & Applications
The rising global interest in surfing and artificial surf reefs reflects a desire to merge coastal protection with recreational value, yet the complexity and mixed success make them a challenging innovation to implement effectively. At International Coastal Management (ICM) , we’ve been involved with artificial surf reef developments for the last 40 years, refining the art of balancing coastal protection with surfing functionality. As coastal communities face increasing challenges from erosion, sea-level rise, and the need for tourism-driven economic growth, the lessons learned from global artificial surfing reef projects can serve as a roadmap for future projects. Table of Contents What are Artificial Surf Reefs? Artificial Surf Reef Design Challenges and Variables Designing for Surfing vs. Coastal Protection Global Artificial Surf Reefs Upcoming Artificial Reef Projects Key Considerations for Successful Artificial Surf Reefs FAQ: Understanding Artificial Surf Reefs Get in Touch Narrowneck Artificial Reef, Australia What are Artificial Surf Reefs? Artificial surf reefs are man-made underwater structures engineered to replicate the benefits of natural reefs. These structures, designed by specialised coastal engienering companies , aim to enhance wave quality by shaping surfable waves, improving wave face cleanliness, and extending ride length. While they are often thought to offer coastal protection by reducing wave energy and minimising beach erosion , in practice, surf reefs rarely achieve both objectives effectively. "Artificial reefs can improve surf conditions, but expectations must be managed. Surfable waves depend on highly variable factors like wave height, period, and wind direction. Designing the ‘perfect wave’ for everyone is not realistic." - Angus Jackson, Founder, International Coastal Management Constructed with materials like geotextile sand containers , rocks, or concrete modules on the ocean floor, artificial surf reefs are typically optimised for either surfing performance or coastal protection, but achieving both simultaneously requires careful trade-offs and compromises. Artificial Surf Reef Design Challenges and Variables Designing an artificial surf reef requires precision and consideration of many variables. The type of breaker, peel angle, and wave height are all critical to achieving a rideable wave. A reef that produces consistent, progressive waves for surfers must account for local seabed contours, wave energy, and target users. Key artificial surf reef design parameters include: Wave Height and Period: Determines the energy and surfability of the wave Breaker Type: Spilling waves suit beginners; plunging waves appeal to advanced surfers Peel Angle: Influences how progressively the wave breaks along its crest, critical for rideable conditions For example, a 1-meter wave will break in water approximately 1 to 1.4 meters deep. The reef’s shape must encourage waves to break progressively along the crest, creating the "peeling" effect desired by surfers. The perfect reef for one group of surfers may not suit another. Beginners benefit from safer, spilling waves, while advanced surfers usually prefer the challenge of steep, plunging breaks. Designing for Surfing vs. Coastal Protection The experience on the Gold Coast highlights a key reality: designing a surf reef is much more complex than it seems. While natural reefs around the world can (in the right conditions) create ideal surfing conditions, replicating this in an engineered structure is not as simple as it sounds. Typical Reef Shapes - ICM The challenge lies in achieving the precise conditions needed to produce a progressive, rideable wave that offers a long, consistent surfing experience. A surf reef requires careful attention to the placement and geometry of the reef’s crest, which must be carefully angled toward the beach to ensure waves break in a way that’s optimal for surfing. In contrast, coastal protection reefs can be more straightforward, often taking the form of submerged breakwaters designed to reduce wave energy and prevent beach erosion. The Gold Coast Artificial Reefs: An Initial Hybrid Approach The Gold Coast provides two distinct case studies for artificial reefs. The Narrowneck Artificial Reef , a hybrid design, was created primarily for coastal protection with surfing as a secondary benefit. In contrast, Palm Beach Artificial Reef was designed as a surf reef, focused on generating a right-hand surf break. Narrowneck Artificial Reef: A Multipurpose Artificial Reef Designed as a multipurpose structure, The Narrowneck Artificial Reef, developed by ICM , was built primarily for coastal protection with a secondary objective to enhance surf conditions. Originally designed in a V-shape to allow for both left- and right-hand rides, this early prototype required adjustments when strong currents were observed in the model, leading to a split in the ‘V’. Due to safety considerations, a proactive decision was made to lower the reef's crest by 1 meter before construction, ensuring a depth of 1.5 meters below the low tide waterline. While Narrowneck ultimately succeeded in its primary role as a coastal stabilisation reef, its surf functionality is limited to specific conditions. It should be noted that the Narrowneck Reef was part of an integrated coastal management approach for The Gold Coast’s northern beaches ( The Northern Gold Coast Beach Protecting Strategy ). The beach at the Narrowneck location should not exist due the large, artificial headland jutting out into the sea compared to the rest of the shoreline. The reef’s focus was to produce a coastal protection structure at low-cost and high-volume, therefore an innovative approach using large, sand filled geotextile containers was developed, producing a significant reef volume (approx. 70,000m³) for AUD$2.3M (approx. AUD$30/m³). The Narrowneck Artificial Headland jutting out into the sea beyond the rest of the coastline, with no accessible beach at high tides (before the artificial reef and NGBPS). Narrowneck ”beach” before the artificial reef (NGBPS) vs 25 years on, with stabilised beach and manmade dune system in lee of the reef. Surfers congregating on the large, built-up sand bank in the lee of the reef (on small swell days) Angus Jackson, our founder, reflects on the surfing element of the reef, saying: "Narrowneck works very well for coastal protection without causing harmful erosion behind the reef. However, as a surf reef, it’s more restricted, performing best when the tide is low and the swell is clean and large." It should be noted that as an underwater structure that helps to retain sand in the nearshore zone, the reef creates greater percentage of use for surf amenity in its vicinity (bulging sand banks around the reef). The excess sand evident in the nearshore zone is typically where surfers can be found. So, can you surf on the reef itself? Sure, if the conditions are right (low tide, 1.5m+ swell and offshore wind) as per the video below. Palm Beach Artificial Surf Reef: Designed for Surfing In contrast to Narrowneck, the Palm Beach Reef was designed to create a high-quality surf break (noting that surfing as a sport has changed dramatically since Narrowneck’s inception in the late 1990’s with significantly higher demand and general performance levels). A significant focus was put on highly complex computer models to achieve the ideal surf outcomes. Built using rock, Palm Beach Reef was significantly more expensive (AUD$18.3M total or approx. AUD$700/m ³) than Narrowneck and focused on producing a higher performance, right-hand surf wave. This surf reef design offers important lessons for those seeking to create artificial surf reefs in other parts of the world. As Angus Jackson explains: "Palm Beach shows that when the objective is surfing, the design can be more focused and effective. But with that comes higher costs, as the materials and precision required for a successful surf reef are significantly greater than those for a coastal protection reef." An artificial reef feasibility study was conducted by ICM and Griffith University in 2004 (presented at the International Surf Reef Conference at Manhattan Beach, California 2005) showcasing that (based on the initial success of Narrowneck Reef as a prototype for artificial reefs) another artificial reef in Palm Beach would be a feasible addition to a beach protection strategy. From there the reef design went through several reports and design stages (by BMT WBM in 2013, DHI in 2017 and a Final Report in 2018 by Royal Huskoning). The Palm Beach Reef demonstrates that surf reefs can achieve their recreational goals, with good waves breaking on the reef in the right conditions (low tide, 1.5m+ swell and offshore wind) and have positive impacts on local sand bars with surf amenity in the lee the reef in smaller/average swell. Palm Beach Reef in relation to other coastal elements. Source: Gold Coast City Council The Palm Beach Reef was located in the lee of a large, natural reef. This can help focus wave energy on the artificial reef. There is also has rock groyne structure inshore of the reef which helps to stabilises the top of the beach. Can you surf on the reef itself? Yes, in the right conditions the reef breaks well. Environmental and Economic Benefits of Artificial Reefs Both reefs on the Gold Coast offer environmental and economic benefits. Artificial reefs, like their natural counterparts, provide habitats for marine life and contribute to improving beach nourishment practices. Additionally, the surf amenities provided by these reefs have attracted tourism, which has been a boom to the local economy. "Both Narrowneck and Palm Beach have enhanced the local surf scene and brought significant environmental benefits. The sandbars formed around Narrowneck, for example, have contributed to the stability of the shoreline while also offering recreational value." - Angus Jackson For other coastal communities, this dual role of artificial reefs, both as coastal protectors and economic drivers through tourism, can be a powerful incentive to explore similar projects. Global Artificial Surf Reefs Artificial reefs have been developed worldwide with varying degrees of success, showcasing the complexities and challenges of combining coastal erosion protection with surfing enhancement. Below is an overview of notable projects, highlighting their objectives, construction methods, and outcomes: Bukitts Reef, Bargara, Queensland (1997) Objective: Surf-only improvement. Materials: Basalt boulders. Construction Method: Existing rocks on the headland were repositioned using an excavator at low tide. Approximate volume: 300m³. Outcome: A cost-effective and community-driven effort that transformed hazardous conditions into a peeling right-hand wave, Angus Jackson of ICM was able to provide valuable input into this pioneering concept. Cables Reef (Cable Station), Western Australia (1998-1999) Objective: Surf-only enhancement. Materials: Limestone rock. Construction Method: Rocks placed from a barge. Approximate volume: 5,000m³. Outcome: Although it created high-quality waves, inconsistent swell conditions limited the Perth artificial surfing reefs effectiveness, with surfable days occurring sporadically. Narrowneck Reef, Gold Coast, Queensland (1999-2000 with a top up in 2017) Objective: Coastal protection with a secondary goal to improve surf quality. Materials: Geotextile sand-filled containers (Terrafix non-woven SFGC). Construction Method: 150-450t mega sandbags placed via hopper dredge. Approximate volume: 70,000m³. Outcome: Narrowneck Reef , designed by ICM, successfully retained sand in the localised area, creating a consistent beach where there had not been before. It created marine biodiversity and surf quality was enhanced but remains limited to specific swell and tide conditions. Pratte’s Reef, California (2000-2001) Objective: Surf enhancement to mitigate the negative impacts of a jetty on local surf conditions. Materials: Geotextile sand-filled containers (Nicolon woven). Construction Method: 14t geotextile containers placed by crane on a barge. Approximate volume: 1,350m³. Outcome: The reef failed to consistently produce quality waves and was dismantled in 2010 due to structural issues and environmental concerns Mount Maunganui Reef, Tauranga, New Zealand (2008) Objective: Improve surfing conditions while enhancing beach width and biodiversity. Materials: Sand-filled geotextile containers (terrafix/elco non-woven) Construction Method: Containers filled in situ, deployed to create a delta-wing-shaped reef. Approximate volume: 6,000m³. Outcome: Produced breaking waves when ideal conditions aligned, but there were construction complications, resulting in hazardous rip currents and eventual removal in 2014. Boscombe Surf Reef, Dorset, England (2009) Objective: Enhance surfing conditions Materials: Geotextile sand-filled containers. Construction Method: Containers filled with local sand. Approximate volume: 13,000m³. Outcome: Initially produced occasional bodyboarding waves but faced structural failures. It was rebranded as a "multi-purpose reef" in 2017 but didn’t meet its original surfing objectives. Kovalam Reef, Kerala, India (2010) Objective: Coastal protection with secondary surf enhancement. Materials: Geotextile sandbags (30m long). Construction Method: Bags placed to create a 100m surfable left-hand wave. Approximate volume: 4,800m³. Outcome: Initially stabilised the beach and improved surf, but structural failure within weeks led to its rapid deterioration. Palm Beach, Australia (2018) Objective: Surfing and coastal protection Materials: Quarried rock approx 25,000m ³ Construction Method: Barge placed quarried rock Outcome: Great surf in ideal conditions with surf amenity in the reef vicinity on sand bars for majority of the time Banbury's Beach, Australia (2018) Objective: Surfing Materials: Floating air pocket Construction Method: Barge placed rubber Outcome: Damaged during installation, not able to function While these reefs showcase the potential of artificial surf reefs, they also highlight the importance of site-specific design and clear project goals. Upcoming Artificial Reef Projects Albany Reef, Australia (TBD) Objective: Surfing Materials: Quarried rock Construction Method: Barge. Outcome: In process. This reef has also been 30 years in the making with initial feasibility study and designs by ICM and Griffith University for the locally lead Surf Group S.O.S and City of Albany. The project was then kicked off again in 2015 and has moved through further design development stages by various other consultants, it’s an exciting one to watch as a purely, surf focused reef. Oceanside, California (TBD) Objective: Coastal protection with secondary surf enhancement. Materials: Quarried rock Construction Method: Barge. Outcome: In process. This reef is part of a coastal revitalising project with the main purpose to retain a sandy beach. ICM is working on the detailed design with GHD. Other Artificial Surf Reefs ICM has developed surf reef designs for locations such as Dubai and Colombia, with these innovative projects awaiting future construction. Modern surf parks/wave pools have also been built globally, specially designed for making waves perfect for surfing at different levels. Key Considerations for Successful Artificial Surf Reefs The success of an artificial surf reef depends on aligning its design with local conditions, user needs, and environmental considerations. As Angus Jackson explains: "The final design of any reef is as much social science as physical science. It must suit the culture, economy, and surf community it serves." The global artificial surf reef projects highlight key takeaways for future reefs: Define Objectives Clearly: Is the reef for surfing, coastal protection, or both? Wave Climate: Evaluate local wave conditions for consistency and quality User Safety: Safety cannot be compromised for public users Materials and Design: Cost and constructability are heavily influenced by material choices Leverage Natural Sediment Processes: Sandbars around reefs can amplify surf conditions. Community Engagement: Align with local needs and priorities to ensure acceptance and long-term support. Account for Maintenance: Ongoing monitoring and maintenance to ensure long-term success. FAQ: Understanding Artificial Surf Reefs Do artificial reefs actually work? Artificial reefs are complex structures that require a balance of science, engineering, and site-specific knowledge to succeed. When done right, they not only protect coastlines but also enhance marine habitats and recreational value. The success of reefs like Narrowneck proves the potential when these factors align. What is the most famous artificial reef? The Narrowneck Artificial Reef on the Gold Coast, Australia, is widely regarded as one of the most renowned. It successfully integrates coastal protection with environmental enhancement and improved surfing during ideal conditions, showcasing the multifaceted benefits of artificial surf reefs. What are the advantages and disadvantages of artificial reefs? Artificial reefs are a long-term investment. Their benefits, like coastal protection, biodiversity enhancement, and recreation, are significant, but they require ongoing management to deliver sustainable results. Get in Touch Whether your goal is coastal erosion protection, surfing enhancement, or both, ICM has the expertise to guide your project. With decades of experience designing innovative, sustainable solutions, we’re ready to help you transform your coastline. Contact us today to learn more.
- Gold Coast Seawalls: A Guide to Protecting Beachfront Property
Living by the ocean offers great views and a unique lifestyle, but it also comes with challenges like coastal erosion and storm surges. For beachfront homeowners, Gold Coast seawalls aren't just a smart investment - it’s a requirement under the City of Gold Coast’s City Plan to protect your property and the surrounding coastline. At International Coastal Management (ICM) , we make the seawalls construction process seamless. From design and certification to final construction sign-off and dune restoration, we handle every step with expertise. Why Do You Need a Seawall? Coastal erosion is a natural process, but it can become a significant risk during storms or high tides. Without adequate protection, your property could lose valuable land or face structural damage. Seawalls in Australia are one line of defence for coastal erosion. On the Gold Coast, it is the responsibility of private property owners and developers to construct and maintain a seawall (to council standards). These are designed to: Prevent property loss and reduce damage from storms. Comply with regulations by meeting City Plan requirements for beachfront properties. Enhance longevity The Gold Coast A-Line The A-Line is the approved alignment for seawall construction along the Gold Coast beaches, established after severe erosion in the 1960s and 1970s. It ensures a consistent and connected seawall system along the coastline, protecting both public and private properties. At ICM, we design seawalls that perfectly align with the A-Line, ensuring they meet Council requirements and integrate seamlessly into the coastal landscape. Steps to Building a Private Seawall on the Gold Coast Building a seawall on the Gold Coast can seem complex, but with ICM, it doesn’t have to be. We’ve simplified the Gold Coast City Council’s 11-step process into manageable actions, ensuring compliance at every stage: 1. Understand the City Plan Requirements Before beginning, review the City Plan Coastal Erosion Hazard Overlay Code and related guidelines and requirements . These documents outline the technical and regulatory standards for seawall construction. ICM Support: Our team breaks down the technical jargon, ensuring you know exactly what’s required. 2. Get the Necessary Approvals You’ll need development applications approved by both the City of Gold Coast and relevant Queensland Government departments for tidal or prescribed tidal works. ICM Advantage: We handle the paperwork for you, from State Government approvals for tidal works to Council permits. 3. Submit the Security Deposit The City of Gold Coast requires a minimum bond before work begins, ensuring satisfactory restoration of dunes and infrastructure, certification and approvals. Why ICM: We'll guide you through the deposit requirements, and ensure your seawall and dune system is built to council standards so your bond can be returned promptly after project completion. 4. Design and Certification Your seawall must be designed by a Registered Professional Engineer of Queensland (RPEQ) to meet Council standards. Why ICM: Our RPEQ-certified engineers bring decades of experience to create designs that are durable, compliant, and environmentally integrated. 5. Pre-Construction Activities Prepare for construction by managing temporary road/pathway closures and ensuring minimal disruption to public access. ICM’s Full-Service Approach: We manage all pre-construction logistics, including obtaining necessary permits. 6. Construction of Seawall Work with a qualified contractor to construct your seawall to Council standards. ICM Expertise: We oversee construction to ensure quality and compliance every step of the way. 7. Restore the Dune and Vegetation After construction, dunes must be reformed with clean sand, native vegetation planted, and dune fencing installed. Our Complete Solution: We integrate dune restoration to ensure your seawall functions as part of a resilient coastal system to council standards. 8. Final Certification and Inspections Submit certifications and inspections to the City of Gold Coast for final approval. ICM’s Commitment: We ensure your seawall and dune system meet the highest standards. Gold Coast Coastal Management To counteract Gold Coast erosion, there are a range of innovative and multifaceted coastal protection measures implemented. Combining coastal protection structures, artificial reefs (like the Narrowneck Artificial Reef ), beach nourishment , and stable dune systems, the region addresses erosion and ensures resilient coastlines. Additionally, sand bypassing and backpassing maintain natural sediment flows, while native vegetation stabilises dunes, providing critical storm buffers and wildlife habitats. This holistic approach balances environmental, community, and surf amenity benefits, safeguarding the coastline for future generations. FAQ: Your Seawall Questions Answered 1. How long does seawall construction take? The timeline varies depending on the complexity of the site but typically ranges from 4 to 5 months. The design and construction of a seawall can be relatively quick (2-4 weeks), however the approval process can take up to 4 months. 2. What’s the typical cost of a seawall? Costs vary based on site conditions, materials, and regulatory requirements. We provide a tailored quote after an initial site assessment. 3. Do I need a seawall if I already have dunes? Dunes are an essential part of coastal resilience but may not be sufficient on their own. Terminal seawalls provide a critical defence against wave action and erosion, especially during storms. 4. Can ICM handle the entire process? Yes! From design and approvals to construction management and dune restoration, ICM is an expert coastal engineering company that offers an end-to-end solution tailored to your property’s needs. 5. Why is dune restoration necessary after building a seawall? Dunes stabilise the area, reduce wind erosion, and enhance the natural resilience of your property. Dune restoration helps your seawall works in harmony with the environment, and is a requirement from the Gold Coast City Council. ICM’s Expertise in Seawall Construction ICM provides end-to-end seawall solutions, including: Design: Engineering seawalls to meet Gold Coast standards. Construction: Managing the building process (working with local contractors) from start to finish. Regulatory Compliance: Navigating the approval process for you. Dune Restoration: Stabilising the site with sand, vegetation, and fencing plans. Our team ensures your seawall not only protects your property but also integrates seamlessly with natural coastal processes , enhancing long-term resilience. Ready to protect your beachfront property? Contact ICM for tailored seawall solutions designed to safeguard your home and investment while meeting Gold Coast regulations.
- Coastal Engineering Companies: How to Choose the Right Firm for Your Project
Coastal environments are constantly changing. Strong tides and storms naturally change the shape of a coastline over time. But with rising sea levels and extreme weather events becoming more frequent, expert coastal engineering companies can play a vital role in protecting shorelines, infrastructure, and communities. But how do you know which coastal engineering company to trust? With so many firms offering erosion control and shoreline protection, it’s crucial to choose a specialist that understands the complexities of coastal processes, regulatory requirements, and nature-based solutions. Table of Contents What Do Coastal Engineering Companies Do? How to Choose the Right Coastal Engineering Company The Gold Coast Coastal Resilience Evolution The Future of Coastal Engineering How to Get Started with ICM What Do Coastal Engineering Companies Do? Coastal engineering is a specialised field of engineering that focuses on managing and protecting coastal zones from natural forces and human impacts . Unlike large civil engineering firms, coastal engineering companies have specialist expertise in designing and implementing coastal solutions that work with natural processes rather than against them. International Coastal Management (ICM) is a globally recognised leader in providing practical, cost-effective, and sustainable coastal solutions. While our head office is located on the Gold Coast, Australia, our expertise extends worldwide, delivering innovative and tailored solutions to coastal challenges. Coastal engineer services include: Seawalls & Erosion Control Structures Beach Nourishment & Sediment Management Artificial Reefs & Nature-Based Solutions Marina & Waterfront Development Coastal Resilience Planning At ICM, we’ve been delivering these solutions for over 40 years, combining engineering expertise with a deep understanding of coastal dynamics to ensure long-term success. How to Choose the Right Coastal Engineering Company Not all coastal engineering companies are created equal. When selecting a partner for your project, consider the following key factors: 1. Experience & Proven Track Record Coastal engineering is complex - real-world experience matters. Look for a company with: Decades of experience handling diverse coastal challenges A strong portfolio of successful projects in various environments International expertise to bring global best practices to local solutions ICM’s Advantage: ICM has safeguarded thousands of miles of coastline across 23+ countries, delivering 1,200+ successful projects. From erosion-prone shorelines to million-dollar waterfront developments, our expertise transforms coastal challenges into lasting, sustainable solutions that protect communities, businesses, and ecosystems. 2. Regulatory Knowledge & Compliance Coastal projects must adhere to strict environmental and regulatory guidelines. The right engineering firm will: Navigate complex approval processes for you Ensure compliance with local, state, and national regulations Provide certified designs that meet marine engineering and environmental standards (location dependant) ICM’s Advantage: We work closely with councils, governments, and private developers to streamline approvals and compliance - so your project stays on track. 3. Specialist vs. Generalist Approach Many civil engineering firms offer coastal engineering as part of a broader service, but coastal resilience requires specialised expertise. Choose a company that: Focuses exclusively on coastal engineering Understands the unique challenges of coastal processes Can design solutions tailored to site-specific conditions ICM’s Advantage: Unlike many firms, ICM is a coastal engineering specialist. We don’t just build structures - we design solutions that work in harmony with nature. 4. Innovative & Sustainable Solutions Today’s coastal projects require innovative solutions that balance protection with sustainability. The best companies will: Incorporate nature-based solutions alongside traditional engineering Use advanced digital modelling to predict long-term effectiveness Focus on ecological benefits, not just hard infrastructure ICM’s Advantage: We’ve developed coastal resilience frameworks and strategies such as the Living Speed Bumps approach, used in Australia, the UAE and soon to be in the United States. 5. Multi-Benefit Project Outcomes The most effective coastal solutions go beyond erosion control - they create economic, environmental, and community benefits. Look for a firm that: Enhances beach amenity and recreational value Supports marine biodiversity and coastal ecosystems Maximises cost-effectiveness without compromising resilience ICM’s Advantage: Our multi-functional coastal solutions have helped cities, developers, and homeowners protect their investments while improving coastal ecosystems. The Gold Coast Coastal Resilience Evolution The Gold Coast, Australia, is a prime example of how integrated coastal engineering strategies can protect shorelines while maintaining beach health. Challenge : Severe beach erosion threatened homes, infrastructure, and tourism. ICM’s Solution : A hybrid approach combining: Terminal seawalls buried under sand dunes to provide hidden protection Beach nourishment & sediment bypassing and backpassing to improve sand processes. Construction of artificial reefs to reduce erosion Dune vegetation planting to strengthen the shoreline Result: A resilient, adaptable system that protects against storms while preserving beach access and ecological value. The Gold Coast: Before & After The Future of Coastal Engineering As climate change accelerates, coastal engineering must evolve. Future directions of the field may include Adaptive engineering designs: Coastal structures designed for adaptability e.g. ability to increase height or width in response to sea level rise Machine learning advancements: Incorporating AI into designs Proactive planning: Integrating nature-based elements with engineered structures, like multifunctional artificial reefs and living shorelines ICM is at the forefront of this evolution, leading pioneering pilot projects worldwide and contributing to global research initiatives. Our expertise extends to serving on high-profile panels, including the United Nations Ocean Decade Expert Panel and the Engineers Australia National Committee on Coastal and Ocean Engineering , shaping the next generation of sustainable coastal solutions. How to Get Started with ICM For private developments, councils/governments, or other design firms looking for coastal expertise, if you’re planning a project, get in touch with us . Our team can provide you with: Expert consultation to assess your site’s needs Customised engineering designs that balance protection & sustainability Implementation and project management from start to finish
- Seawall Requirements for Gold Coast Developments
The Gold Coast is one of Australia’s most dynamic and sought-after coastal regions. For developers, this presents incredible opportunities but also unique challenges. Coastal erosion and strict regulatory requirements mean that any beachfront development must review, construct and maintain a seawall to Gold Coast City Council standards. At International Coastal Management (ICM) , we partner with developers to design and implement seawalls that meet these standards while supporting sustainable and profitable developments. Why Developers Need Certified Seawalls As a developer, you’re responsible for ensuring that new beachfront projects comply with the City Plan Coastal Erosion Hazard Overlay Code . This includes constructing certified terminal seawalls along the A-Line before any development begins. Understanding the advantages of seawalls is crucial, as they not only provide long-term shoreline stability but also ensure compliance with regulatory requirements. These seawalls are designed to: Prevent property loss and reduce damage from storms. Comply with regulations by meeting City Plan requirements for beachfront properties. Enhance longevity Gold Coast Regulations Seawalls on the Gold Coast must align with the A-Line, established after major storms in the 1960s and 1970s. This ensures a continuous, and connected terminal seawall system along the coast, protecting both public and private property. Alongside this, key regulations include: Standard Seawall Design Drawings for consistent construction Coastal dune restoration and fencing requirements Environmental impact assessments for tidal and prescribed tidal works Steps to Build a Seawall for Your Gold Coast Development At ICM, we have been reviewing, designing and constructing terminal seawalls on the Gold Coast for over 40 years. Our RPEQ certified engineers will guide you through the process, ensuring your seawall is durable and compliant with all council standards. Below is a summary of the Gold Coast Requirements. 1. Review the City Plan and Guidelines Review the City Plan Coastal Erosion Hazard Overlay Code and related guidelines and requirements . These documents outline the standards for seawall construction. 2. Obtain Approvals Secure development permits from: City of Gold Coast Relevant Queensland Government departments for tidal works The Gold Coast City also requires a bond before work begins, to ensure satisfactory restoration of dunes, infrastructure, certification and approvals. 3. Engage Coastal Engineering Experts Your seawall must be designed by a Registered Professional Engineer of Queensland (RPEQ) and built to meet strict standards. At ICM , Our RPEQ-certified engineers bring decades of experience to create designs that are durable, compliant, and environmentally integrated. 4. Construct and Certify the Seawall Use an experienced team like ICM to ensure compliance with pre-construction requirements, construction regulations and quality standards. 5. Dune Restoration After seawall development, dunes must be reformed with clean sand, native vegetation, and have dune protection fencing installed as required. ICM’s Expertise for Developers ICM is your trusted partner in seawall construction, offering: Turnkey Solutions: From design to final certification Compliance Expertise: Navigating local and state regulatory requirements Sustainable Practices: Incorporating dune restoration and nature-based solutions Track Record: Over 1,200 successful coastal projects completed worldwide Our solutions not only meet the Gold Coast’s standards but also enhance the sustainability and market appeal of your development. Contact us for a free quote today.
- Beree-Badalla Boardwalk Coastal Impact Assessment
The Beree-Badalla Boardwalk, a 40-year-old elevated timber structure along Currumbin Creek, is set to be upgraded by the City of Gold Coast. ICM conducted a comprehensive Coastal Processes Impact Assessment to ensure the proposed design is resilient to erosion and inundation risks in this sensitive tidal nature reserve. Existing Beree-Badalla Boardwalk to be upgrade Project Details Client : Planit Consulting (for the City of Gold Coast) Date : 2022 Location : Currumbin Creek, Gold Coast, QLD About This Project The Challenge The Beree-Badalla Boardwalk, spanning 1.2km over the tidal nature reserve along Currumbin Creek, provides pedestrian access. After 40 years of service, the City of Gold Coast is planning to replace it with an upgraded structure. Situated within the Coastal Management District and an Erosion Prone Area, the project required a Coastal Processes Impact Assessment. The Solution ICM, engaged as sub-consultants by Planit Consulting, provided critical coastal engineering input to support the Development Application. The team undertook a thorough Coastal Processes Impact Assessment, which included: Data Review and Analysis : ICM reviewed available site data, including historic aerial imagery, surveys, previous reports, state mapping, geotechnical data and conducted a site inspection. These insights informed a conceptual coastal processes model that was developed to understand site-specific dynamics. Impact Assessment : The proposed alignment’s vulnerability to inundation and erosion was rigorously assessed. The impact assessment found that the proposed alignment was suitable, with recommended scour depth provided for boardwalk piles. These analyses and recommendations ensure the upgraded Beree-Badalla Boardwalk is resilient, sustainable, and capable of serving the community needs. “This project reflects our commitment to sustainable, resilient design in sensitive coastal environments, ensuring infrastructure supports both the community and the natural ecosystem.” – Angus Jackson, Founder, International Coastal Management Services Provided Site inspection and review Coastal Processes Impact Assessment Responses to State Code 8 and Schedule 3 Get in Touch ICM specialises in coastal engineering solutions that integrate resilience, sustainability, and regulatory compliance. If you’re planning infrastructure upgrades or coastal developments, contact our team of experts to ensure your project is designed for long-term success.
- Artificial Reefs and Nearshore Nourishment on the Gold Coast: Real-World Results
The beaches and world-class surf breaks of the Gold Coast have long been regarded as the crown jewels of Australia's coastal landscape. The Gold Coast is one of the most popular tourist destinations in the country. However, preserving this coastal charm requires more than nature's hand; rather, it necessitates creative and environmentally responsible approaches to coastal management. Artificial reefs, nearshore nourishment and bypassing systems are at the forefront of these advancements. These initiatives were spearheaded by the efforts of Angus Jackson in the early 80's (as the Gold Coast City's Coastal Engineer) and subsequently by International Coastal Management (ICM), his post-council consultancy. Source: Gold Coast City The Need for Change Historically, the Gold Coast's coastline was shaped and reshaped by the forces of nature—storms, tides, and currents. However, as the 20th century progressed and urban development surged, the natural equilibrium of these beaches began to waver. The 1960s and 70's bore witness to this delicate balance tipping, as severe swell events became more frequent, causing significant erosion and threatening both the natural beauty and the burgeoning tourism industry of the region. Traditional coastal erosion solutions , such as dredging and beach nourishment, became the immediate recourse. While these methods provided temporary relief, they were just that—ephemeral. The recurring costs, both financial and environmental, of these interventions were becoming untenable. It was in this challenging backdrop that visionaries and coastal management experts began to explore alternative, sustainable solutions. The focus shifted from merely reactive measures to proactive, long-term strategies. The idea was not just to combat erosion but to enhance the coastline's recreational and ecological value looking at more nature based solutions . This forward-thinking approach set the stage for innovations like artificial reefs—structures designed to promote sand accumulation and dissipate wave energy, thereby reducing erosion. Piloting for Success Instead of just putting solutions into place, the Gold Coast used a process of piloting and monitoring. With this proactive plan, the area became what could be called a full-scale coastal laboratory. With each project, a lot of monitoring and feedback loops were set up so that real-world results could be used to guide future projects. Because of this commitment to solutions based on facts, the Gold Coast has become known around the world as a model for smart and flexible coastal management. Milestone Projects A series of landmark projects chart the path of the Gold Coast's transformation: Narrowneck Artificial Reef Serving as both a coastal protection measure and a surfing amenity, this reef became a benchmark in artificial reef design . Continuous monitoring has shown geomorphological changes to littoral sand drift. This has caused a buildup of sand around the reef, helping to reduce erosion and offering added surf benefits on sandbanks. Notably, the reef was constructed using geotextile sand containers , which were approximately 1/3 the cost of a rock reef construction. This cost-effective approach was consistent with the pilot nature of the project. Succesful Outcomes: Demonstrated successful use of geotextile sandbags, offering cost-effective reef construction. Induced geomorphological changes, leading to sand build-up around the reef. Reduced coastal erosion and enhanced surfing conditions due to formed sandbanks. Here are some extracts from the latests scientific review of Narrowneck Reef after 20 years and the way that it interacts with the sand morphology. From the paper "Sediment pathways and morphodynamic response to a multi-purpose artificial reef -New insights" . "Twenty years after Narrowneck construction, the MPAR has shown a localised effect on the nearshore morphology that helps to maintain the beach in a similar state compared to the adjacent areas whereas it was previously more vulnerable (i.e. a hotspot). Sediment transport pathways are shown to occur both inshore and offshore of the reef, under varying hydrodynamic and morphodynamic conditions. This study has identified scenarios whereby a previously unforeseen deposition of sand downdrift of the reef occurs in the sub-tidal region." "The deposition process, associated with the presence of the MPAR, aids in coastal protection by dissipating incoming wave energy, before it reaches the shoreline and provides a temporary sediment store to feed the downdrift areas (Figure 36-8) in a process that is akin to headland sand bypassing (Short and Masselink, 1999; Klein et al, 2020) and moreover, it is closely linked to the wave height and direction (Vieira da Silva et al., 2018b). This is likely the reason why the downdift erosion expected during design phase (Turner et al, 2001) has not been observed in the data." "Twenty years after construction, the Narrowneck reef site has more sand deposited updrift and the longshore transport seems to have re-established with minimal impacts on the upper beach. The location of the reef within the active surf zone worked as planned allowing sand to bypass inshore of the reef, particularly under modal wave conditions. Although not initially expected, the results presented in this work demonstrate that the sand bypassing can also occurs offshore of the structure under certain conditions (large oblique waves). Whilst a persistent salient at the shoreline was not observed in the dataset presented here, Narrowneck reef evidently does affect the sediment transport and morphological changes in the short-term, helping to sustain the overall medium to long-term increased volume of sand while allowing sand to also bypass the reef and continue downdrift without significant negative impacts." "The short-term morphological response to the MPAR after two decades is more closely related to the deflection of longshore currents as they encounter the reef than to the dissipation of wave energy, mainly because MPARs are designed to dissipate just enough wave energy so that the wave can still be surfed." Sand Bypassing Systems (Nerang and Tweed Rivers) Recognizing the importance of maintaining navigational access and natural sand flow, sand bypassing systems were established at both the Nerang and Tweed Rivers. They've led the way in coastal management, with additional benefits observed in surf conditions at places like the Superbank and South Stradbroke Island. These systems not only ensured uninterrupted sand delivery to nourish southern beaches but also played a pivotal role in mitigating erosion. Succesful Outcomes: Pioneered sustainable coastal management, ensuring uninterrupted sand delivery. Improved navigational access and natural sand flow. Enhanced surf conditions at iconic spots like the Superbank and South Stradbroke Island. Source: Gold Coast City Palm Beach Artificial Reef (PBAR) Informed by the monitoring results from Narrowneck, PBAR was completed in September 2019. Recent Wave Peel Tracking (WPT) has shown the development of sandbank surf breaks around the reef. Ongoing surveys also indicate that the nourished sand remains retained around the reef, enhancing the coastal landscape and supporting its recreational potential. Succesful Outcomes: Used monitoring results from Narrowneck for informed design and implementation. Wave Peel Tracking (WPT) indicated the development of desirable sandbank surf breaks around the reef. Ongoing surveys showed retained nourished sand around the reef, indicating long-term effectiveness. Aerial of sand build up and interruption around reef The 2017 Gold Coast Beach Nourishment Project (GCBNP) Spanning June to September 2017, this project added over 3 million cubic meters of sand to the Gold Coast's beaches. The project utilised the novel nearshore nourishment approach to achieve high volumes. Survey results five years post-implementation indicate that a commendable 75% of the nourished sand at Palm Beach still remains within the system. This retention is believed to be due to the combination of nearshore nourishment and the Palm Beach reef, which have jointly contributed to sand retention despite facing significant storms over the past half-decade. This project was built on decades of research and development in the field of mass nourishment, led by Angus Jackson and ICM. Succesful Outcomes: Successfully added over 3 million cubic meters of sand to vulnerable beach sections. Five-year post-implementation surveys revealed 75% of nourished sand at Palm Beach still within the system. Proved the combined efficacy of nearshore nourishment and the Palm Beach reef, retaining sand even after significant storm events. Some Key Successes The accomplishments stemming from these projects are manifold: Sustained Sand Retention : Post GCBNP, a remarkable 75% of the nourished sand remained active within the beach system, underscoring the project's efficacy. Revitalized Surf Conditions : The emergence of surf-conducive sandbanks adjacent to the artificial reefs, especially the right-hander near PBAR, bolstered the region's recreational appeal. The Road Ahead The tale of the Gold Coast's artificial reefs and nearshore nourishment is one of innovation, resilience, and sustainable progress. However, as any coastal engineer or environmentalist would attest, coastlines are inherently dynamic zones. Their ever-changing nature, shaped by tides, currents, and human activities, mandates a proactive and adaptive approach to management. As we stand at the cusp of a future marked by climate change challenges, the significance of ongoing monitoring cannot be understated. The lessons learned from each project on the Gold Coast serve as stepping stones, guiding the next phase of innovations. The insights gleaned from the past become particularly vital as we grapple with the looming threats of sea-level rise and increased storm events. Predicted changes, fueled by global warming, will undeniably reshape our coastal landscapes, making the field of coastal engineering in Australia and globally even more crucial. Building upon the foundation laid by trailblazers like Angus Jackson and the entire team at International Coastal Management (ICM), the future will see coastal management strategies that are not only reactive but also anticipatory. Harnessing the symbiotic alliance of science, engineering, and the nature based solutions , we can ensure the Gold Coast's legacy endures, not just as a testament to its past glories, but as a beacon of hope and resilience in the face of future challenges. Acknowledgements An acknowledgment is due to the Gold Coast city and their dedicated team, both past and present. Their unwavering support and openness to pilot projects have been instrumental in advancing coastal management strategies. Their emphasis on rigorous monitoring and development has set a benchmark for other coastal regions to emulate. Additionally, a special mention goes out to the consultants and contractors who have seamlessly integrated into the Gold Coast coastal management team. Their expertise, commitment, and collaborative spirit have been invaluable in shaping the Gold Coast's legacy as a pioneer in sustainable coastal management.
- 45+ Years of Coastal Resilience Design: Angus Jackson's Legacy on the Gold Coast
Discovering an article from the 1989 edition of Engineers Australia detailing Angus Jackson's innovative approach to combating beach erosion on the Gold Coast was like uncovering a time capsule filled with visionary predictions for coastal management. It's fascinating to reflect on the relevance of Angus Jackson's work today, as we witness the tangible outcomes of his strategies. His predictions, once hopes for a future at risk, have materialised into significant successes. The iconic nourishment techniques, dune management, multi-purpose artificial reefs, sand bypassing and comprehensive coastal preservation efforts he envisioned have not only safeguarded the Gold Coast's beaches but also served as a model for global coastal resilience. Engineers Australia Magazine 1989 As we look back, it's clear that Jackson's foresight and dedication have left an indelible mark on the field of coastal engineering in Australia and globally, offering lessons on the power of innovation and the critical importance of harmonizing human activity with nature's dynamics. This article serves as a testament to the enduring impact of visionary thinking in addressing environmental challenges, proving that proactive and innovative solutions can create a sustainable future for communities worldwide. Northern Gold Coast How it Started In the late 70's and early 80's, the Gold Coast's sparkling beaches faced a dire threat from erosion, endangering both its environmental treasure and booming tourism sector. Angus Jackson, a coastal engineer with foresight and innovation, embarked on a journey that would not only redefine coastal management on the Gold Coast but also set a global benchmark for shoreline preservation. His strategic interventions, well-documented over the decades, reveal a legacy of success, innovation, and environmental stewardship that continues to inspire. Gold Coast beaches in the late 70's [visulalightbox.com.au] Pioneering Nearshore Nourishment Facing the erosion crisis, Jackson, then supervising engineer for special projects at the Gold Coast City Council, pioneered a nearshore nourishment (sand placement) program in 1985. His approach was revolutionary: "to work with nature." This initiative aimed to replenish the beaches naturally, complementing an existing beach nourishment program that began in 1974 after a critical study by Holland’s Delft Hydraulics Laboratory. Jackson began his works with the Gold Coast City in 1976 and would lead to the confidence in this approach was palpable. He famously stated, “Either Christmas '89 is a good beach, or I'm looking for a new job,” underscoring his commitment and belief in the project's success. Nearshore Nourishment Success The foresight and effectiveness of Jackson's strategies were not merely speculative. Over the years, the success of these initiatives has been extensively documented, showcasing not just the revitalization of the Gold Coast's beaches but also marking significant progress in coastal management practices globally. Jackson's work extended beyond sand replenishment; he was instrumental in developing vegetated dunes on top of gold coast seawalls , sand management, and monitoring procedures that stand as a testament to sustainable coastal resilience. Coastal Innovations that Resonated Globally Angus' influence expanded internationally through his company International Coastal Management , where he championed the multi-purpose artificial reef approach at Narrowneck utilising geotextile sand containers . This innovative solution for coastal stabilization, over two decades later, is celebrated for its multifaceted success in environmental, recreational, and protective dimensions. "The creation of the large nearshore shoals has modified the wave climate and given immediate protection to the foreshore," Jackson observed, highlighting the project's immediate benefits. A recent study on the sediment transport around the Narrowneck Reef highlights that it is having a positive effect on stabilising the beach around the reef, improving marine habitat and providing surf amenity in the reef vicinity. Research and Education in Coastal Resilience Jackson's work through council and International Coastal Management laid the groundwork for ongoing research and education in coastal resilience. He played a pivotal role in establishing the Griffith University Centre for Coastal Management department (now called Coastal Marine and Research Centre ), aiming to preserve the accumulated knowledge and continue the advancement of coastal adaptation techniques and lessons. This initiative has made the Gold Coast a hub for cutting-edge research and a beacon for communities worldwide striving to enhance their coastal adaptability. A Future Built on Foundations of the Past Today, the Gold Coast shines as a prime example of how vision, innovation, and commitment can transform environmental challenges into success stories. Angus Jackson's legacy is not just in the sands of the Gold Coast but in the global community of coastal management, where his strategies and teachings continue to inspire action and innovation. In a world facing the urgent challenges of climate change and rising sea levels, the work initiated by Jackson and carried forward by entities like International Coastal Management and Griffith University have proven that coastal management strategies can have a multitude of benefits while providing ongoing resilience. It underscores the importance of embracing innovative solutions and fostering knowledge-sharing communities to protect our planet's precious coastal environments for future generations. The Gold Coast, once damaged by eroding coastlines, now exemplifies the power of sustainable intervention and working with nature. Marine habitat crated on Narrowneck Multi Purpose Artificial Reef The Future of Coastal Resilience With our recent win in the RE:BEACH design competition in Oceanside, California up against world leading design consultants and teams, International Coastal Management have been awarded the chance to design and implement a coastal resilience approach based on the success of the Gold Coast. The design approach includes a multi purpose artificial reef, nearshore nourishment, sand/dune management plan and sand bypassing . This could be the new blueprint for coastal adaption methods in southern California. Angus Jackson with new company director Aaron Salyer after RE:BEACH win on Gold Coast beach The full Engineers Australia 1989 Article You can read the Engineers Australia article below. Looking for Coastal Resilience and Adaptation Specialists? With decades at the leading edge of coastal resilience design and management approaches, International Coastal Management (ICM), have a dedicated and passionate team working in the coastal resilience space. From coastal management strategies to multi purpose artificial reefs, vegetated dune systems or sand nourishment programs, our team can assist with all levels from concept designs to budgeting, implementation and monitoring.
- Coastal Engineering Explained: What is it and why it matters for coastal protection
The coastline represents a dynamic and constantly evolving boundary between land and sea, shaped by natural forces such as tides, storms, and erosion. Coastal engineering plays an essential role in managing and protecting this delicate interface, where large sandy beaches can swiftly transform into vulnerable zones during adverse weather events. This specialised field applies scientific and engineering principles to stabilise shorelines, mitigate erosion, and enhance resilience against coastal hazards. If you are looking for an experienced coastal engineering company , understanding the history and importance of this discipline can provide valuable insights into the expertise required to manage our coastlines effectively. Let's dive deep into the world of coastal engineering. Table of Contents What is Coastal Engineering? What does a Coastal Engineer do? Why is Coastal Engineering Needed? A Brief History of Coastal Engineering Coastal Engineering in the Modern Era Coastal Engineering Pilot Projects Managing the Coastline: A Journey towards Coastal Resilience The Future of Coastal Engineering Coastal Engineering Solutions What is Coastal Engineering? Coastal engineering is a specialised field within civil engineering focused on managing and protecting coastal zones from natural forces and human impacts. This discipline combines scientific analysis and engineering practices to understand and address coastal dynamics, including wave behaviour, sediment transport, erosion, and sea-level changes. Coastal engineers develop solutions that enhance shoreline stability, safeguard against flooding, and support sustainable coastal use, utilising advanced modelling and design techniques to predict the effects of both natural events and engineered interventions. What does a Coastal Engineer do? At its core, coastal engineering combines principles from geology, oceanography, civil engineering, and environmental science to develop solutions for protecting and enhancing coastal environments. Coastal engineers undertake various tasks, such as: Designing and Constructing Protective Structures: Coastal engineers design and build seawalls, revetments, breakwaters, artificial reefs, and groynes to protect against erosion and rising sea levels. These structures are essential in managing coastal erosion, and exploring the advantages and disadvantages of seawalls can provide insights into their effectiveness and limitations. Developing Multi-Purpose Coastal Strategies and Structures: Coastal engineering involves creating structures that ensure safe navigation for vessels, manage sediment transport, and enhance recreational and environmental value. For instance, artificial reefs can offer both coastal protection and recreational benefits. Exploring multi-purpose artificial reefs illustrates how these structures contribute to coastal resilience. Restoring and Replenishing Beaches: Coastal engineers work to counteract erosion by replenishing beaches and restoring coastal dunes, which serve as natural barriers against waves and storm surges. Techniques like nearshore nourishment help maintain beach stability, while coastal dunes offer a sustainable, nature-based approach to coastal resilience. Managing Coastal Habitats and Biodiversity: Coastal zones support diverse ecosystems, and coastal engineers play a role in protecting these habitats. By implementing nature-based solutions, they can balance human activity with environmental preservation. For example, nature-based solutions can enhance both biodiversity and shoreline resilience. Coastal engineers also consider habitat creation when designing coastal structures, as discussed in the power of adaptation through nature-based solutions . Addressing Societal Challenges with Sustainable Solutions: Coastal engineers often address challenges related to climate change, urbanisation, and community resilience. Their work in adapting nature-based solutions to societal needs highlights how these strategies align with long-term sustainability goals while managing coastal infrastructure. Why is Coastal Engineering Needed? Coastal engineering is essential for shaping and protecting our coastal environments, tackling the complex challenges posed by erosion, rising sea levels, and expanding human development. By blending science, technology, and environmental sustainability, coastal engineers address the myriad of challenges and opportunities presented by the dynamic interface between land and sea, driving progress towards a resilient and sustainable coastal future. Climate Change and Sea-Level Rise: As climate change accelerates sea-level rise and intensifies storm events, coastal engineering plays a crucial role in protecting vulnerable coastal areas. Coastal engineers design adaptable, resilient strategies to mitigate flooding risks, manage erosion, and stabilise shorelines. Techniques like beach erosion prevention solutions and coastal sandbypassing systems are examples of proactive measures that enhance shoreline resilience. Economic Importance: Coastal engineering is integral to the functioning of ports and harbors, which serve as essential hubs for international trade. By managing sediment transport, navigational requirements, and structural stability, coastal engineers ensure the efficient operation of these facilities, supporting global commerce and regional economic growth. Marina Development Marinas are vital to the tourism and recreational economy, providing safe harbors for boats and enhancing the appeal of coastal areas. Coastal engineers design and develop marinas to withstand coastal dynamics, manage sedimentation, and ensure safe navigation. Tourism and Recreation: Coastal tourism is a major economic driver, drawing millions to beaches each year. Coastal engineers are responsible for keeping beach communities appealing while also ensuring their visitors safety. They manage beach nourishment projects, the design of recreational facilities, the implementation of measures to preserve the natural beauty of coastal landscapes, and beach erosion prevention solutions all of which contribute to the growth of the tourism industry. Environmental Conservation: Coastal areas are home to ecosystems that are both diverse and fragile, both of which are essential to the survival of marine life. Coastal engineers are essential to the preservation of the natural environment because of the crucial role they play in the design of environmentally friendly coastal structures, the restoration of degraded habitats, and the development of sustainable management practices. In order to protect marine life and keep our oceans in good health, it is essential to strike a balance between the demands of development and the need to preserve ecological integrity. Public Safety and Risk Management: Coastal engineers devise methods of hazard prevention and early warning systems in order to save lives and protect property from natural disasters that can occur along coastlines, such as hurricanes, tsunamis, and storm surges. They improve community preparedness and reduce the negative effects of disasters by conducting risk assessments and vulnerability analyses, which provides input for land-use planning and emergency response strategies . Research and Knowledge Generation: Understanding coastal processes, developing new technologies, and improving engineering practices all require ongoing research and the generation of new knowledge in the field of coastal engineering. Coastal engineers contribute to the advancement of science by carrying out field studies, developing models, and publishing research findings . This process enriches the existing body of collective knowledge and encourages innovation within the sector. A Brief History of Coastal Engineering Coastal engineering can be traced back to ancient civilizations, where its roots were first established. Harbors and fortifications against the sea were famously developed by the Egyptians, Greeks, and Romans, respectively. While Australia's early indigenous technologies included weirs and dams for manipulating the coastal zone for aquaculture. Coastal Engineering in the Modern Era The Dutch Influence The Dutch have been at the forefront of modern coastal engineering for centuries. This is due to the fact that a sizeable portion of the Netherlands is located at or below sea level. The development of novel coastal defences is absolutely essential to the survival of the country. Their ingenious systems of dikes, dams, and storm surge barriers, such as the world-famous Delta Works, have set global standards for the prevention of flooding and the management of water resources. In addition, the Dutch method of coastal engineering is not solely focused on preventing water from entering the land; rather, it emphasizes finding ways to coexist with water. This harmonious coexistence with water is demonstrated by ideas such as "Room for the River," which make it possible for certain areas to flood without risk, as well as by the construction of floating homes. This comprehensive and forward-thinking approach has not only helped to preserve the Dutch landscape, but it has also inspired coastal management strategies all over the world. These strategies place an emphasis on adaptability, sustainability, and a profound respect for the natural environment. The United States Army Corps of Engineers Influence As we move into to the modern era, the United States Army Corps of Engineers (USACE) becomes an increasingly important player. The USACE was established in 1802, and its initial focus was on military fortifications and navigational routes. On the other hand, as the United States grew and became more industrialised, the role of the Corps of Engineers in coastal engineering became more prominent. They were in charge of a number of projects, some of which included the construction of lighthouses, jetties, and extensive beach nourishment. Their research, innovations, and in-depth studies of coastal areas have shaped a significant portion of the best practices that are currently used in the field. The Gold Coast Influence Since the 1970's, the Gold Coast has become a living laboratory for modern coastal engineering, and a place where pioneering projects have been tested and monitored. The region's proactive approach to coastal management has led to the development and refinement of techniques that have had a significant impact on coastal engineering practices around the world. These techniques have also had an impact on the development of new techniques. The Gold Coast has established new standards for environmentally responsible beach nourishment, coastal protection structures, and habitat restoration thanks to a number of innovative projects. Lessons in resiliency, adaptability, and harmony with nature can be learned through continuous observation and study of this living coastal lab, which has yielded priceless insights into the dynamic interactions between various coastal elements. International Coastal Management is proud to be a pioneering player in the Gold Coast's history of modern coastal engineering. Initiating projects like the sand bypassing system , nearshore nourishment , artificial reefs , and developing seawalls with vegetated dunes, ICM continues to play a role in the Gold Coast's coastal management strategy. Dubai's Influence The word "innovative" has come to be synonymous with coastal engineering in Dubai, which pushes the limits of what is conceivable and achievable. The iconic projects that the emirate has undertaken in the past, such as the Palm Jumeirah and The World Islands, have brought about a revolution in coastal development and demonstrated the potential to form new landforms in marine environments. These man-made archipelagos, built with meticulously placed sand and rock, are not only marvels of engineering but also testaments to human ingenuity and ambition. The construction of these archipelagos required a great deal of planning and precision. The efforts that Dubai has put forth have prompted advancements in dredging and land reclamation technologies, which have made it possible for seascapes to be transformed into areas that are habitable, functional, and luxurious. However, these monumental projects have also sparked discussions and reflections on environmental sustainability, ecological impact, and long-term viability, prompting coastal engineers and environmentalists to seek balanced solutions that harmonize development desires with ecological prudence. International Coastal Management has been involved in a variety of Dubai's coastal projects over the last couple of decades. From the World Islands to multiple private island developments and coastal structures, with expansion of projects across the UAE and many of the Middle Eastern countries including Bahrain and Qatar. Coastal Engineering Pilot Projects Theories and designs alone can only get us so far in any field of science or engineering. Any coastal engineering project will really be put to the test when it is used in real life. Because of this, pilot projects become an essential strategy. Coastal engineers can keep an eye on results, collect data, and improve their methods by using smaller-scale experiments. The history of man-made reefs is a great example of this. In the past, man-made reefs were mostly made of concrete, old tires, or even ships that had been taken out of service. But in order to find better solutions that are better for the environment and work better, people tried using different materials. The Narrowneck Reef in Australia is a great example of this new way of doing things. The reef was made with geotextile sand containers instead of known building materials. The reef material and construction were specifically designed for the project, forcing development in the field. It was meant to protect the coast and provide a place for recreation. The Narrowneck Reef's success not only taught us a lot about how to use different kinds of materials, but it also showed how coastal protection and better recreation can go hand in hand. Furthermore, the realm of beach nourishment has seen significant advancements, thanks to pioneering work by experts like Angus Jackson . Traditional beach nourishment involved depositing sand from offshore sources directly onto eroding beaches. Jackson's innovative method, termed nearshore nourishment , shifted the deposition zone to the nearshore area. This method, developed on the Gold Coast, allows natural wave processes to distribute the sand, offering a more sustainable and effective approach to beach replenishment. Such pilot projects and their subsequent monitoring have enriched the field of coastal engineering. They've provided invaluable insights, refined methodologies, and underscored the importance of adaptability in the face of dynamic coastal challenges. Managing the Coastline: A Journey towards Coastal Resilience Taking care of the coastline is like taking care of a living thing. It takes constant work, the ability to adapt, and a deep understanding of how natural processes and human actions affect each other. When carefully planned and put into action, coastal management strategies can make coastal areas much more resilient, allowing them to thrive even as environmental problems get worse. The Gold Coast in Australia is a great example of how good coastal management can change things. Over the years, many different plans have been used to deal with problems like beach erosion, storm damage, and rising sea levels. Building groynes, coming up with new ways to nourish beaches, and creating man-made reefs like the Narrowneck Reef have all been very important in making the Gold Coast stronger and more resilient. By keeping a careful balance between environmental, recreational, and protective goals, the Gold Coast is a shining example for other coastal areas that want to make their coastlines more adaptive and long-lasting. The Future of Coastal Engineering As we venture into the heart of the 21st century, coastal engineering stands at the crossroads of innovation and adaptation. Here's a glimpse into the future: 1. Embracing Green Engineering: "Soft" solutions will be used more and more along with traditional "hard" solutions like sea walls and breakwaters. Using natural materials and ecosystems, like mangroves and oyster reefs, to make living shorelines that protect the coast and increase biodiversity is part of this. Encouraging Nature Based Solutions , like the Noosa River Oyster Reef Project is something that ICM integrate into our design approach. 2. Innovative Technology: Engineers will be able to more accurately predict how the coast will change thanks to improvements in technology, AI, and modeling tools. Drones and pictures taken by satellites will also help keep an eye on and manage coastal areas. At ICM we have been using drones (both aerial and hydrographic) over the years to improve our on-site data recording ablitites. While for desktop studies, the improvement in 'citizen science' technologies like the "Coast Snap" app are providing useful data that can feed into our designs. 3. Sustainable Urban Planning With a significant portion of the world's population living near coasts, there's an impending need for sustainable coastal urbanization. This involves creating resilient infrastructure that can withstand extreme events and sea-level rise. At ICM we always involved in adaptive and resilient coastal projects, though see the need for greater reliance as we head into the near future. 4. Collaborative Efforts As coastal challenges become increasingly global, international collaboration will be paramount. Sharing knowledge, technology, and best practices will drive global resilience. The development of "Knowledge Hubs" such as the Gold Coast's own developed by Griffith Coastal Management Department is critical. 5. Education and Advocacy: Coastal engineers will play a vital role in educating policymakers, stakeholders, and the general public about the importance of sustainable coastal management. This will ensure informed decision-making and greater community involvement. Coastal Engineering Solutions Coastal engineering, deeply rooted in its rich history, is evolving rapidly to meet the challenges of today and tomorrow. If you're in search of a coastal engineering firm that not only understands the legacy of the past but also has its eyes set on the future, International Coastal Management is your ideal partner. Join us as we shape the future of our coastlines, ensuring they remain vibrant, safe, and resilient for generations to come.
- Corinella Nature-Based Foreshore Design
ICM worked with the Department of Energy, Environment and Climate Action (DEECA) to develop a high-priority hybrid salt marsh restoration design for the Corinella foreshore, addressing erosion risks and enhancing coastal resilience. This innovative nature-based solution (NBS) balances ecological restoration with shoreline protection in response to climate change and sea-level rise. Project Details Client: Department of Energy, Environment, and Climate Action (DEECA) Date: 2024 Location: Corinella Foreshore, Western Port Bay, Victoria, Australia About This Project The Challenge The Corinella foreshore faced escalating erosion risks and habitat degradation due to rising sea levels and increased coastal pressures. A previous site evaluation ranked Corinella as a prime candidate for a nature-based restoration trial, but significant knowledge gaps remained regarding site suitability and specific design requirements. The Solution ICM conducted comprehensive site investigations to assess and validate the feasibility of a hybrid saltmarsh nature-based method. Key actions included: Site Analysis: Conducted foreshore and intertidal surveys, geotechnical sediment sampling, and flora/fauna studies. Hydrological and Stormwater Assessments: Analysed stormwater catchment, outfall quality, and tidal conditions to determine restoration viability. Design Recommendations: Proposed a hybrid supported saltmarsh restoration design, including fill material placement to adjust bed levels, rock sills to stabilise the shoreline, and saltmarsh planting with native species. Priority Zones: Identified high-priority restoration areas with the greatest ecological and coastal protection potential. The final design integrates stormwater systems and supports biodiversity while enhancing the site’s resilience to erosion and climate impacts. “The Corinella saltmarsh project demonstrates how nature-based solutions can address coastal challenges while fostering ecological renewal and community benefits.” – Sam King, Project Lead, International Coastal Management Services Provided Site Investigation and Suitability Analysis Geotechnical and Ecological Surveys Concept and Detailed Design of Hybrid Saltmarsh Restoration High-Level Hydrological and Coastal Processes Assessment Recommendations for Nature-Based Interventions Get in Touch ICM is at the forefront of designing and implementing nature-based solutions that balance ecological restoration with resilient coastal protection. Contact us to learn how we can help transform your coastline sustainably.
- Advantages and Disadvantages of Seawalls (by Seawall Designers)
To protect beach amenity value, the prevention of coastal erosion is critical. With factors like climate change and sea level rise there's never been more need for well designed measures against coastal erosion. Seawalls are a great example of one solution. But is a seawall suitable for your site/project? This article reviews the advantages and disadvantages of seawalls and how to determine suitability for you site. What is a seawall? A seawall is a manmade barrier constructed where the land meets the sea. Their main purposes are: To prevent land loss through the coastal erosion process To hold the land in position, creating a permanent/fixed border in the case of marine infrastructure, like marinas or harbours. There are many different types of seawall (both in design and material makeup), that perform differently under various exposed conditions. And there is not necessarily one ‘best’ kind of seawall, as each site has its own unique requirements and interacts with the dynamic coastal environment in their own way. In most cases, seawalls are exposed to the natural conditions and can therefore be seen. This can disrupt the aesthetic of a location. However, without the seawall, the natural conditions may be subject to serious erosional damage and land loss. This may be due to natural causes, such as high wave conditions, or man-made changes, such as disruption to the coastline/the natural sand and water flow which can create erosion ‘hotspots’ that need coastal erosion solutions . Types of Seawalls While the advantages and disadvantages of seawalls can vary depending on the design, several factors influence which type is best suited for your site. These factors include: Cost Visual aesthetic Sit location in the coastal zone Functionality and usability Impact on the site/environment These factors should be taken into consideration when choosing the right type of seawall for the site to deter from unwanted disadvantages of seawalls. The most common types of seawall include: Sloped Sewall Stepped Seawall Vertical Sewall Curved Sewall Stacked or Module Seawall There are also combinations of the above mentioned. And, each of these different types of seawalls can be made of different types of material (discussed in the following sections). Emergency or Temporary Seawalls In many coastal locations around the globe the beaches are considered government or state land. Typically, in these instances, government approvals are required before there can be any construction of seawall structures (especially if they are going to directly touch/impact the beach). In some cases, where there is a direct threat to property or infrastructure, an emergency or temporary seawall may be installed/constructed without going through the typical approval process. Note that regulations can very significantly between states and local governments, so it is always best to check on which approvals are required (as some locations implement what is called 'managed retreat' whereby you may not be able to build any kind of seawall, temporary or not). Emergency or temporary seawalls can be built quickly and are often made using material that is easy to remove if/when it is necessary. These include materials like geotextile sand containers and other emergency flood protection filling modules. Advantages and Disadvantages of Seawalls for Emergency Works Like all coastal erosion protection structures there are advantages and disadvantages, with the emergency or temporary works there are a few things to consider. Advantages: Typically, works can be performed quickly bypassing the lengthy approval process required for some other types of seawalls Generally, as the emergency or temporary works are not designed for longevity, they can be built cheaper (depending on the materials used/site conditions) that traditionally, long-term, exposed seawalls In many cases, the emergency works could be removed if necessary. Disadvantages: Quick installation of emergency works may not be the best long-term solution and therefore, the temp works may need to be removed at some point for better long term solutions Quick, cheap solutions may not have the best aesthetic to match the site Exposed Seawalls This is the most common type of seawall. These seawalls are designed to be permanently exposed to the ocean and wave environment. Seawalls interact with the coastal processes of a sandy beach in terms of onshore/offshore sand transport and local longshore sand transport when present in the active zone. Numerous papers evaluate the influence of seawalls based on their location in the active prism and the long-term beach stability – accreting, stable, nourished, or eroding [2]. Nevertheless, a popular and too simplistic idea prevails that seawalls cause coastal erosion and destroy beaches. Consequently, seawalls are often disregarded during option evaluations. An exposed seawall in the surf zone under wave attack would result in reflection and scour in front of the wall and/or accelerated erosion along the seawall, despite eroded volumes being 60 percent of what they would be without the seawall [1]. Refer to ICM’s Coastal Conference Paper on Terminal Seawalls for more info. Advantages and Disadvantages of Seawalls that are Exposed Advantages The biggest and most obvious advantage of exposed seawalls is that they mitigate wave energy from hitting the landmass Exposed seawalls can be used to reshape natural or man-made coastal areas by creating a solid edge/definitive line In most cases, seawalls are used to prevent land loss behind the wall, thereby preserving property or infrastructure Disadvantages Seawalls by design stop/reduce wave energy from passing through or over the wall. This wave energy therefore is either reflected or redistributed somewhere else. Often, part of the wave energy is reflected back to the sea which can create an erosion hotspot at the base of the seawall itself (referred to as scour). Through proper coastal engineering design, scour can be accounted for and therefore built into the seawall design to reduce the scour effect If seawalls are built out of the natural beach alignment the can act as a kind of groyne and disrupt the longshore sand transport to beaches/properties on the leeward side of the wall Exposed seawalls look man-made (as they are) and can therefore take away from the natural beauty of a site (atheistic interruption) It should be noted that proper designed seawalls by experienced coastal engineers can improve site protection and mitigate negative impacts. Get in touch today to speak with real coastal engineering experts in the field of rock wall design . Terminal Seawalls Seawalls that are situated as far inland as possible from "normal" beach changes are termed terminal seawalls. These structures are only active during severe erosion events and remain buried under normal circumstances. A terminal wall, which is often buried within the dune buffer zone, limits erosion during severe events and serves as a clear planning boundary between the active beach and permitted development. Due to the fact that these occurrences may only occur for brief periods a few times per hundred years, the potential for negative impacts on the beach is equally brief. Advantages and Disadvantages of Terminal Seawalls Advantages One of the greatest advantages of terminal seawalls over exposed seawalls is there low visual impact As the seawall only becomes exposed during an extreme event, the storm demand is sourced from almost the entire upper beach profile and not just scour at the base of the seawall. The waves are generally depth limited and of smaller magnitude, resulting in a smaller structure with lower design requirements, less toe scour, and less overtopping Disadvantages Terminal seawalls only come into effect during extreme events when the rest of the beach profile has become eroded and are therefore a ‘last line of defences’ approach Think a terminal seawall may be suitable for your site? Revetment walls Revetment walls are essentially 'small' seawalls that are designed to absorb wave energy and reduce erosion. They can be sloped, stepped, or vertical walls made from durable materials such as rock, concrete, or geotextile containers (for emergency works). By dispersing the force of water, revetments protect canals, riverbanks, and infrastructure from damage during high tides, storms and floods. How they work: Retain and protect land from erosion Absorb wave energy to prevent structural damage Serve as critical infrastructure for coastal and water-front properties Materials used for seawalls As mentioned previously, there are a wide range of materials used for seawalls. Each will have their own advantages and disadvantages depending on the site. Hard engineering design often refers to materials in seawalls such as: Rock Concrete Steel Gabions (rock baskets) Wood Composite Materials There are also ‘softer’ approaches using technologies such as: Sand filled geotextile containers Self-standing sand filled modules Green solutions are considered dune vegetation or landscaping. While this would not be considered a stand-alone seawall solution, it is often incorporated into the design process to reduce the visual impact and add a more ‘natural’ look to the site on completion. How Effective are Seawalls? Seawall effectiveness comes down to design and installation execution and can vary significantly (depending on how well the design is done). Seawalls can be very effective at protecting landmass from wave impact/erosion. In most cases it is not a question of the seawalls effectiveness of protecting the immediate site, however, how the seawall interacts with the surrounding coastal environment and adjacent sites is often the area of concern. When designing and installing seawalls, careful consideration should be taken into the long-term effects of the wall on the surrounding area. In conjunction with other coastal protection measures like beach nourishment, seawalls can be very effective in maintain both stable beaches and secure property lines. Do Seawalls Stop Tsunamis? Seawalls can be designed for a wide range of impact possibilities and wave conditions. From small waves (boat wake and wash), to large wave events such as Tsunamis and significant storm surge events. Experienced coastal engineers can determine which wave conditions need to be considered when designing seawalls at a site and can accommodate this into the design process. Designing and building seawalls to stop Tsunamis would require for instance, larger/heavier rock or modules with thicker overall width and higher design crests. Do Seawalls Erode Beaches? As discussed, there is a misconception that seawalls only erode beaches. One of the disadvantages of seawalls (if not designed properly) is that they can have negative effect on the immediate beach, through wave reflection and scour. They can also have negative effects on the surrounding beaches and adjacent properties. If designed properly inconjunction with a hollistic approach to coastal protection, they can be very effective. Therefore, it is critical to engage with experienced coastal engineers when considering seawalls as a solution for your site. Are Seawalls Sustainable? Sustainability in design can consider a few different elements: The materials used The impact on the site (and surrounding sites) Sustainability relative to the materials themselves will vary greatly depending on the material source relative the proposed site. For example, quarried rock is often used is seawall design and construction. In areas with accessibility to quarried rock (assuming the quarries themselves are operated in a sustainable way, which may relate to things like volume of rock available vs. time impact on the environment, etc.) the rock may be a viable choice with relatively low transport costs associated. In areas where no quarried rock is available, there may be options to ship in rock or use locally available material such as coral rock, or sand (into containers). In summary, there is no clear-cut answer to sustainability in seawalls as each site and design will vary significantly. It should be noted that sustainability in design is something that needs to be considered for a holistic approach. Are seawalls expensive? The cost of a seawall at different sites can vary significantly. Factor effecting cost include: The design itself Some sites will require larger seawalls to protect against high power wave/storm conditions Some sites will require smaller walls The material Depending on which material type is used it will determine the constructability and associated costs, transport to site costs, etc. In all coastal erosion protection design there are few different costs to consider: Capital cost The upfront cost to design and build the structure The maintenance cost Any ongoing maintenance that may be required In general, higher capital cost require lower ongoing maintenance. Whereas lower capital cost may require more ongoing/higher maintenance costs. Are seawalls affordable to maintain? As mentioned above, the maintenance cost of seawalls will depend heavily on the type of design and material used. For example, at a remote site where no quarried rock is available, coral rock may be used which would be a lower capital cost than importing quarried rock. However, over time, the coral rock will not likely hold up in storm conditions as long as quarry rock. Therefore, the coral rock seawall may need to be maintained with additional coral rock or completely replaced. These kinds of capital vs. long term costs will need to be considered when deciding on seawall material and design. What are the Advantages and Disadvantages of Seawalls? In summary, there are plenty of advantages and disadvantaged of seawalls. For the most part, seawalls are a very effective way of maintaining a structural line for land and property protection. The main disadvantages of seawalls are that they can create localised erosion. This can be at the base of the seawall itself or at adjacent properties. If designed properly in conjunction with a hollisitc approrach to site resilience building, seawalls can be very effective. Looking at implementing a seawall to your property? Be sure to consult with an industry professional (experienced coastal engineer). Or if you're looking for seawall alternatives, consider a variety of coastal resilient measures like Multi Purpose Artificial Reefs in conjunction with nearshore nourishment . Contact us today for consultation to determine which seawall is right for you. Read more about artificial reefs or sand bypassing systems as a coastal erosion solution. References: [1] Barnett, M.R., "Laboratory Study of the Effects of a Vertical Seawall on Beach Profile Response," UFL/COEL-87/005, University of Florida, Coastal & Oceanographic Engineering Department, Gainesville, FL, May, 1987. [2] Dean, R. G. and Dalrymple, R. A. (2004). Coastal Processes and Engineering Applications. Cambridge University Press. pp. 404-406