Wamberal Beach Terminal Protection and Sand Nourishment - Investigation and Concept Design

Introduction

The Gosford Beaches Coastal Zone Management Plan (CZMP) contains an action to progress a long-term solution for Wamberal Beach erosion. The CZMP outlines a preferred protection solution (terminal protection structure) and the technical studies needed to inform further decision making, but it does not provide for the delivery of a seawall and sand nourishment. 

On 29 January 2019, Central Coast Council resolved to work with the NSW Government to progress designs for a terminal protection structure (seawall) at Wamberal. Manly Hydraulics Laboratory (MHL) were engaged to complete coastal assessments and develop concept plans for a long-term solution for Wamberal Beach in May 2020.

Following the July 2020 storm event which saw the emergency response place 2,400 tonnes of large rocks, over 2,000 tonnes of rock bags and 4,000 tonnes of sand along Wamberal Beach, the NSW Government Wamberal Seawall Advisory Taskforce was set up to provide technical advice and assistance to Council in progressing a long-term solution for Wamberal.

There are many technical, financial, social and environmental complexities that need to be worked through to develop the long-term solution. Council understands that the best coastal erosion management solutions are developed when state and local governments, residents and the broader community work together.

Council has engaged the Wamberal and broader Central Coast community throughout this project.

View the consultation information here! 

View the technical studies here! 
 

Frequently asked questions

Why is Council investigating options for a terminal protection structure (seawall) and sand nourishment Wamberal Beach?

Wamberal Beach has a long history of coastal erosion, with beachside infrastructure exposed to impacts from coastal storms.

The Gosford Beaches Coastal Zone Management Plan (CZMP) outlines a terminal protection structure (seawall) and sand nourishment as the preferred course of action for managing identified coastal hazard threats at Wamberal Beach. 

A technical study was progressed to provide options to more sustainably manage the erosion threat over the longer-term. Council looked at options to improve the community access and beach amenity condition, as part of the long term solution.

Who recommended a terminal protection structure (seawall) and sand nourishment for Wamberal Beach?

The terminal protection structure (seawall) and sand nourishment have been recommended by experts as a preferred erosion strategy at Wamberal Beach for several decades. 

In the mid-1990s a Coastal Processes Study (PWD, 1994) and Coastline Management Plan (WBM, 1995) detailed the nature of the erosion issue and recommended either ongoing sand nourishment or a terminal protection in the form of a seawall. “a terminal protection structure in the nature of a buried rock revetment is to be designed and constructed to the satisfaction of Council and NSW Public Works, such construction to occur as soon as practicable and in an orderly, co-ordinated manner”

In the late 1990’s a range of coastal protection options were proposed by WRL (1998) for Council. A ‘Seabee’ seawall, spanning lagoon to lagoon, was designed and modelled in detail.

An Environmental Impact Statement (EIS) for the coastal protection solution was finalised in 2003 by MHL, which found that a seawall with periodic small-scale sand nourishment was acceptable. Council adopted the EIS for the seawall and sand nourishment solution in 2004. Funding however could not be secured and the approved protection works did not progress further.

Most recently, Council investigated the erosion issue and what to do about it, through a Coastal Hazard Definition Study (CHDS, 2015), a Coastal Zone Management Study (CZMS, 2017) and the preparation of a Coastal Zone Management Plan (CZMP, 2017). The Gosford Beaches CZMP outlines actions to address the erosion risks at Wamberal Beach. Sand nourishment and a terminal protection structure (seawall) was again determined to be the best solution to the long standing issue.

What is the Gosford Beaches Coastal Zone Management Plan?

The NSW Government has laws in place that guide how the NSW coastline is managed.

Coastal Zone Management Plans (CZMPs) identify coastal management issues and the actions required to address these issues.

The Gosford Beaches CZMP was prepared in line the state government legislation, and in consultation with the Central Coast community. The plan was certified by the Minister for the Environment in May 2017 and identifies several key management actions for Wamberal Beach, including:

  • TW11:  Terminal protection- Council to action review, design and funding of terminal protection structure for Wamberal 
  • TW14:  Investigation of sources of sand and determination of the feasibility of beach nourishment for Wamberal Beach
  • TW15:  Beach nourishment coupled with a terminal revetment to increase the buffer against storm erosion.

Were the community consulted through the CZMP?

The community were consulted as part of the Gosford Beaches Coastal Zone Management Plan (CZMP; 2017), and preceding Coastal Zone Management Study (CZMS; 2015). A CZMP Community Engagement Strategy was developed and endorsed by Council in November 2013, this document guided consultation throughout the CZMS – CZMP processes.

Community consultation included:

  • public exhibition of draft documents (CZMS, CZMP)
  • CZMS - targeted community presentations to discuss potential management options for each study area, including Terrigal/Wamberal (2015)
  • community drop-in sessions (include at Terrigal SLSC; 2015)
  • public notices
  • promotion via local newspaper.

In addition, workshops were held with the Council’s Catchments and Coast (advisory) coastal sub-committee established at that time.
 

What is the role of the Wamberal Seawall Advisory Taskforce?

The NSW Government established the Wamberal Seawall Advisory Taskforce on 31 July 2020 to provide Council with support to implement a sustainable long term solution to coastal erosion issues at Wamberal Beach. Dr Phil Watson was appointed as the Chair of the Taskforce with Council’s CEO, Member for Terrigal Adam Crouch MP, representatives from the Department of Planning, Industry and Environment, and Council’s appointed project manager. 

The scope of the Taskforce was ‘advisory’ in nature. The Taskforce meets on monthly basis.  More information on the Wamberal Seawall Advisory Taskforce is available on our website.
 

What is the MHL coastal engineering and economics study?

In May 2020, Council engaged Manly Hydraulics Laboratory to prepare concept plans for a terminal protection structure (seawall) and sand nourishment solutions for Wamberal Beach. The study included: 

  • literature review, to take stock of what is known and identify any information gaps 
  • coastal protection assessment, to determine sand movement, beach behaviour and impacts/opportunities around public access and amenity 
  • concept design options for a terminal protection structure (seawall) and sand nourishment, and potential seawall alignment 
  • sand nourishment investigation to help maintain public beach amenity
  • cost benefit analysis to guide development of possible funding models. 

The results of these technical studies will allow Council and the community to make an informed decision on the best combination of protection and sand nourishment options for Wamberal Beach.

Read the reports and find out more on the technical studies here! 
 

Who will decide if a terminal protection structure (seawall) and sand nourishment works program is delivered?

There are many stakeholders involved in this decision-making process including: Council, NSW Government, beachside property owners, interest groups and the broader community members.

It is important to understand that while sand nourishment coupled with a terminal protection structure (seawall) has been identified as the preferred long-term solution for Wamberal Beach, the Gosford Beaches CZMP does not provide for the construction of a seawall. Indeed, the solution is complex - requiring input and agreement from a number of parties.

There are many steps to work through before a long-term solution can be implemented at Wamberal Beach. Finding a solution that strikes the right balance is not straight forward. Technical, financial, environmental, social, legislative and land ownership challenges must be addressed. 

There is no guarantee that all the factors required to facilitate the seawall and sand nourishment solution will be satisfied. However, in the absence of a long-term solution the risk of further erosion impacts will remain and the result will be continued emergency works which are costly and not designed for long term protection.

Was retreat (buy back) being considered?

Council has no planned retreat policy. The resolution of Council was to proceed with MHL coastal engineering and economics assessment, consistent with the Gosford Beaches Coastal Zone Management Plan:

38/19 - That Council request the Chief Executive Officer to commence the Wamberal Terminal Protection and Sand Nourishment preliminary investigations and concept design.

Council is looking into the costs of potential erosion solutions and potential funding models. 

Any long-term solution must be technically feasible, legally permissible, environmentally and socially acceptable and financially viable. 

Further information on Planned Retreat being onsidered as part of the Cost Benefit Analysis (CBA) is available in the “The Cost Benefit Analysis mentions planned retreat, is that a viable option?” FAQ listed on the technical studies page. 
 

How would the terminal protection structure (seawall) component of the long-term solution impact the beach?

There is no simple answer to this question. 

There are many different factors that determine if a seawall structure will interact with waves and the beach. 

  • Seawall location and alignment: The location of a seawall relative to the beach profile that moves back and forth over time is important. Did you know that seawalls located behind the active beach do not interact with waves under most circumstances? There are many seawalls that co-exist with healthy, high quality beaches. Manly, Bondi and Newcastle (main beach, not Stockton) are good examples of this situation.
  • Type of seawall and its geographical footprint: In locations like Wamberal Beach sloping rock revetments typically interact with waves and beach more than vertical seawalls, which can be placed further landward on the beach. This is because the sloping structures take up more space on the beach. A range of seawall types were investigated for Wamberal.

The coastal engineering study looked at behaviour at Wamberal Beach and assessed coastal impacts from the proposed program of works, including the impact on public access and beach amenity both now and into the future.  Climate change impacts were also considered. 

Did you know that ad hoc protection works have been placed at Wamberal Beach for many decades? 

From Terrigal Lagoon to the Wamberal Surf Life Saving Club, the beach is backed by rocks, building rubble and other works. These materials have been placed in front of the erosion scarp by various entities since the 1970’s. 

When Wamberal is in an eroded state, the ad hoc protection materials interact with the waves. When the beach system naturally recovers (builds out) over time, the rock and rubble become buried. A properly designed and constructed seawall would interact with the beach in a similar way, but in a more effective and less hazardous manner.

Replacing the ad hoc coastal protection works, with a properly designed and constructed seawall that improves beach access and amenity is one of several broader community benefits a long term solution would deliver. 
 

What is sand nourishment?

Sand nourishment involves placement of sand on a beach to combat against erosion and improve beach amenity.

Sand nourishment can involve placing small or large quantities of sand into a beach system. Sand can be delivered to the dry beach face or placed underwater in the surf zone. 

The placement method is somewhat dependant on the method of how the sand is extracted elsewhere and transported to the beach. 

Guidelines for Sand Nourishment Science and Synthesis for NSW have been developed by the NSW Government. 
 

Was sand nourishment being considered?

The preferred long-term solution for Wamberal Beach includes a sand nourishment program to ensure long-term outcomes for Wamberal Beach.

Sand nourishment requirements, resources and cost estimates can be found in the Stage 4 Sand Nourishment Report of the MHL study. 

Has Council applied for funding from the $83.6 million available from the State Government’s Coastal Management Grants Program?

In August 2018 Council successfully lodged a grant application to the NSW Government to receive funding for the investigation and design phase of a preferred long-term (seawall and sand nourishment) solution. The application did not include construction of a seawall.

The coastal engineering and economics study was co-funded (50:50) through the NSW Coastal and Estuaries Grants Program.

Community consultation

The consultation on community values and uses for Wamberal Beach and supporting studies and concept plans have now concluded.

Phase one community consultation 

Between 9 November and 7 December 2020, Central Coast Council conducted phase one community consultation which included a values and uses survey for Wamberal Beach, drop-in formation sessions at Erina Fair and Wamberal Surf Life Saving Club as well as virtual drop-in sessions. We also hosted an online question and answer tool. 

Council undertook the values and uses survey to better understand the value of Wamberal Beach to the community, how it was being used prior to the emergency works and how it is being used now (post emergency works). 

The community can: 

Phase two community consultation 

Between 29 July and 10 September 2021, Central Coast Council undertook phase two community consultation which included the release of studies (1-4) and concept design renders. This phase of the consultation provided an opportunity for the community to provide feedback on the five concept options via an online interactive tool. Drop in information session were also hosted. 

Council sought community feedback on the concept options available to provide a visual aid for the community on what each of the five terminal protection options could look like. 

The community can: 

Phase three community consultation 

Between 17 February and 20 March 2022, Central Coast Council undertook phase three community consultation which included the release of six technical reports supporting the Wamberal Terminal Protection and Sand Nourishment – Investigation and Concept Design project. This phase of the consultation provided an opportunity for the community to provide feedback on the technical reports via an online feedback form. 

The community can: 

Feedback collected during the consultation periods was used to inform the development of the draft Wamberal Beach Terminal Protection Structure Engineering Design Requirements. 

View the project introduction here! 

View the technical studies here! 

Your attention is drawn to the provisions of the Government Information (Public Access) Act 2009 which allows for possible access to certain public and personal documentation. View our privacy statement.

Faqs View

How could the broader community get involved during the phase 1 consultation? 

During the phase 1 consultation, the community were invited to: 

  • complete the online values and uses survey (now closed)
  • speak with project staff and coastal experts at community information sessions (there were in person and virtual sessions available) 
  • submit a question online and have the project team get back to them

How could the broader community get involved during the phase 2 consultation? 

Stage reports 1-4 along with supporting concept design renders were made available for public review as part of phase 2 consultation. 

The available reports include:

  • Stage 1 Literature Review - to take stock of what is known and identify any information gaps.
  • Stage 2 Coastal Protection Assessment - to determine sand movement, beach behaviour and impacts/opportunities around public access and amenity. 
  • Stage 3 Concept Design Options - for a terminal protection structure (seawall) and sand nourishment, and potential seawall alignment.
  • Stage 4 Sand Nourishment Investigation - to help maintain public beach amenity.

During the phase 2 consultation, the community were invited to: 

  • view the technical studies (1-4) 
  • provide feedback on the interactive concept designs via the online tool
  • speak with project staff and coastal experts at community information sessions 
     

How could the broader community get involved during the phase 3 consultation? 

During the phase 3 consultation, the community were invited to: 

  • view the technical reports 1-6 
  • provide feedback via the online feedback form
     

Technical studies

The Wamberal Beach Terminal Protection and Sand Nourishment studies are now complete. The reports include:

Next steps

A review of the technical studies, results from the community consultation and consideration of Councils role in relation to coastal erosion has highlighted the need for any terminal protection structure to be:

  • located as far landward as possible,
  • located wholly on private property where possible
  • asset to be constructed, owned and maintained by property owners 
  • seawall to have the narrowest footprint (to reduce erosion/beach encroachment)
  • have the least sand nourishment requirements (both upfront and during the maintenance phase)

While the requirement to meet that criteria highlights options 3 and 4 (which are vertical seawalls) as the preferred designs similar designs that meet the same criteria may be acceptable. The criteria to be met is: 

  • Any terminal protection structure is to be located wholly on private property where possible
  • The asset will need to be constructed, owned and maintained by property owners 
  • The structure needs to have the narrowest footprint, to reduce erosion/beach encroachment)
  • The structure will have the least sand nourishment requirements, both upfront and during the maintenance phase

Council engaged coastal engineers to develop Engineering Design Requirements  which will identify specific criteria to guide coastal protection development applications at Wamberal Beach. These guidelines are on public exhibition between 29 June and 27 July 2022 for the community to review and provide submissions. Further information on the Wamberal Beach Terminal Protection Structure Engineering Design Requirements is available here. 

You can view the project introduction here and read more about the community consultation here
 

Faqs View

What was involved in Stage 1 Literature Review?

Stage 1 was to take stock of what is known and identify any information gaps. The objective for this study was to review previous studies related to coastal hazards and coastal management and previous design of terminal protection for Wamberal Beach.

The report contains a compiled review and summary of over 30 studies relevant to the context of the Wamberal Terminal Coastal Protection Assessment.

The Stage 1 report is a review of all of the previous studies, how will this review and the learnings from the previous studies be used to inform decision-making around a preferred solution for Wamberal Beach this time?

Stage 1 outlines information relevant to the context of the Wamberal Terminal Coastal Protection Assessment, demonstrating a long history of coastal erosion. Our understanding of coastal processes and engineering have advanced since the development of those studies, which have influenced new design options being presented in the current studies. 

Information gaps in the previous CBA were identified and have been used to inform the new CBA undertaken, particularly by including a distributional analysis.

Previous studies demonstrated funding as a downfall to progression of any long-term solution for Wamberal Beach. 

What was involved in Stage 2 Coastal Protection Assessment?

Stage 2 determined sand movement, beach behaviour and impacts/opportunities around public access and amenity. Objectives for this study included:

  • existing profile data assembly
  • geotechnical data review
  • preliminary crest alignment
  • beach width analysis
  • impact assessment to beach users and beach amenity.

What was involved in the Stage 3 Concept Design Options?

Stage 3 entailed concept design options for a terminal protection structure (seawall), sand nourishment requirements and potential seawall alignment. Objectives for this study included:

  • crest alignment
  • seawall options – rock, vertical, stepped and hybrid
  • cost estimates
  • minimum engineering standards.

A total of five seawall concept designs have been developed with cross-section drawings and footprint mapping. The designs range from revetment to vertical and promenade style structures. This study also includes a review of the relevant engineering standards.

Concept render designs were developed as part of the stage 3 report to assist in visualising the concept seawall design options, the concept renders were used to assist in the phase two community consultation.  Seawall alignment, access points and terminal ends would be determined during the detailed design phase.

Have environmental studies been undertaken in accordance with the current study?

No. The environmental studies would be undertaken as part of a detailed design phase. 

Environmental studies/approvals are a legislative requirement for the construction of a terminal protection structure and sand nourishment operations.

What are the beach amenity impacts of the proposed seawall options for Wamberal Beach? 

Table 5.4 Summary of amenity impacts of proposed options for Wamberal Beach (extracted from Stage 2 – Coastal Protection Amenity Assessment) lists impacts for each option.

Table 5.4
Table 5.4 Summary of amenity impacts of proposed options for Wamberal Beach.

Where would the terminal protection structure (seawall) be located? On public land or private land? Will land be purchased if a terminal seawall is built on private property?

The Stage 3 coastal engineering assessment proposes terminal protection structure (seawall) alignments for various concept options. Proposed footprints of each concept option can be shown in the report (available online). All concept designs have a proportion of their footprint in private land with large footprint designs (rock revetments and promenade) extending further seaward into public land.

It is important to note that these alignments are concept designs. True alignment would be determined during a detailed design phase and would involve seeking consensus between private and public landholders.

Developing a methodology that can support the coordinated delivery of an embayment-wide solution across a mix of private and public land is one of the key challenges that needs to be worked through.

There are no plans in place to purchase private property.
 

What was involved in the Stage 4 Sand Nourishment Investigation?

Stage 4 outlines sand nourishment requirements for Wamberal Beach and investigation of potential sand sources including indicative unit cost estimates. Objectives for the study include:

  • sand requirements
  • sand sources
  • sand nourishment cost estimates.

The key objective of Stage 4 is to provide an acceptable level of public beach amenity for the Wamberal/Terrigal embayment over the life of a terminal protection structure. 

Does the existing Environment and Planning legislation allow for sand nourishment from alternate sources?

It is possible to use sand from alternate sources but a particular type of sand is required. Where sand is sourced alternatively (i.e. not from the same beach embayment) it must be first deemed a viable source by demonstrating similar characteristics such as grain size/colour and be free of contaminants. The Guidelines for Sand Nourishment Science and Synthesis for NSW is the guiding document for sand nourishment in NSW.

Any operations involving sand nourishment would require environmental assessment and possible environmental protection licences dependent on how sand is applied (i.e. offshore vs on land). The Environment Protection Authority (EPA) issues environment protection licences under the Protection of the Environment Operations Act 1997 (POEO Act).

Sand nourishment operations at Wamberal Beach must be consistent with the Coastal Management Act 2016 and State Environmental Planning Policy (Coastal Management) 2018.

What was involved in the Stage 5 Coastal Monitoring Studies?

Stage 5 consists of additional coastal monitoring studies to observe past and present-day beach conditions to better understand the natural fluctuation of the beach. Monitoring includes:

  • installation of a Coastsnap monitoring site on Terrigal Drive
  • installation of Trailcam, Lidar wave runup monitoring station 
  • live Coastal Monitoring Public Webpage to display monitoring data.

View the webpage here!

What was involved in the Stage 6 Cost Benefit Analysis? 

The Cost Benefit Analysis (CBA) assesses the full range of costs and benefits associated with the five concept design protection alternatives (compared to the base case “do normal” approach) to consider economic trade-offs for options to manage future coastal hazards at Wamberal Beach. Also included is a Distributional Analysis (DA) which demonstrates how costs and benefits are distributed. Principles of the report:

  • assess the costs and benefits of options for managing the identified threat posed by coastal erosion to Wamberal
  • understand the social and economic impacts of each option in terms of housing, local tourism, environmental benefits, beach amenity, supporting industries and the long-term viability of Wamberal.

The CBA and DA will guide the development of possible funding models. The funding model proposal will be a requirement of the DA application.

What information was used to inform the updated Cost Benefit Analysis (CBA)? How will this information differ to the previous CBAs developed? 

Information gaps in the previous CBA were identified and have been used to inform the new CBA. This included present day costs and a Distributional Analysis (DA) which demonstrates how costs and benefits are distributed.

Council also provided Balmoral economists with beach use data from the Surf Live Saving Club to assist in determining beach value. 

The costs of associated emergency/ongoing maintenance works have been included to assist in predicting the costs of the “do normal” (or do nothing) approach, which was not considered in the previous CBA.  

What methodology was used in development of Cost Benefit Analysis (CBA)?

The economic analysis was undertaken by economists from the Balmoral Group Australia (BGA). The CBA was developed in accordance with the Department of Planning, Industry and Environment Guidelines for using cost-benefit analysis to assess coastal management options (DPIE, Sep 2020), coastal engineering inputs and advice from the MHL and WRL project team, and findings from the subsequent stages of the MHL project. 

Economic analyses for coastal management is an evolving area of research due to the many variables that make up the coastal zone. The CBA has attempted to resolve many of the assumptions and uncertainties particularly around interpreting the coastal hazard lines. 

Terminology used in the CBA:

Net Present Value (NPV) - a method used to determine the current value of all future cash flows generated by a project, including the initial capital investment. 

Benefit Cost Ratio (BCR) – a ratio used in a cost-benefit analysis to summarise the overall relationship between the relative costs and benefits of a proposed project. If a project has a BCR greater than 1.0, the project is expected to deliver a positive net present value.

Discount Rate – is the rate that converts future values into present values. The discount rates are 3%, 7%and 10%. By applying a discount rate to future cash flows, the required rate of return is taken into account in the net present value calculation.
 

Which terminal protection option achieves the highest net present value? 

All five options achieve positive NPVs between +$33.1M to +$53.7M over 30-years using a 7% discount rate. Of these alternatives, Option 3 (vertical seawall) is indicated to achieve the highest NPV (+$53.7M).

Option 5 (tired seawall with promenade) was also a strong performer achieving a much higher NPV due to improved accessibility and increased visitation.

Central estimates used as inputs into the CBA and are only marginal, and well within the bounds of natural error and uncertainty. Therefore, the results of sensitivity tests, and qualitative factors are expected to play an instrumental role in identifying a preferred option. Careful consideration of aesthetic and other factors difficult to monetarise (such as the significant height of vertical seawalls following major storms) will be required in identifying a preferred option and mitigating any undesirable effects as part of detailed design. 

What is the result of the distributional analysis?

All seawall options achieve a positive net present value which means benefits outweigh costs. For all options the majority of benefit falls to the Beachfront Homeowners with the protection provided to private property at-risk to coastal hazards. 

Some additional benefit for Options 3-5 (Option 3&4 vertical wall, Option 5 promenade) flows to Non-Beachfront Homeowners with improved beach width relative to the encroachment of present ad-hoc rock works. Option 5 delivers a larger share of benefits to the General Community in the LGA, in addition to the benefits flowing to Beachfront and Non-beachfront Homeowners. 

Does the Cost Benefit Analysis (CBA) determine the preferred solution to address erosion at Wamberal Beach?

No. The CBA is only one tool in the decision making. While the CBA provides important information on project costs and who benefits from a seawall, there are many other factors that must be taken into consideration. Such as:

  • Viability of each option (sand nourishment requirements, material sourcing, ongoing costs)
  • Environmental concerns and constraints
  • Community sentiment/feedback 
  • Asset ownership
  • Ongoing maintenance costs

 All factors must be taken into account to determine the best outcome for Wamberal Beach.
 

The Cost Benefit Analysis mentions planned retreat, is that a viable option?

Planned retreat was not included in the scope of the CBA as there is no present policy or mechanism for property reacquisition under planned retreat. Planned retreat was not a recommended action of the certified Coastal Zone Management Plan for Wamberal Beach, in part because it achieved negative present values in previous studies. 

Due to ongoing advocacy for some models of planned retreat by some community members, planned retreat is considered in the sensitivity analysis of the report however, these prove economically unviable. 

It is important to note that the cost of planned retreat would also need to include demolishing, disposal at landfill and dune remediation which makes this option even less viable.

What is Councils plan for the “68 dwellings identified as potentially impacted by coastal hazards by 2050”? will development applications be assessed? 

Any Development Application (DA) submitted will be considered on its merits under the relevant planning controls and certified CZMP.

Can beachfront property owners conduct coastal protection works on their land?

Coastal protection works are subject to an approved development application (DA). Property owners can submit a DA at any time. Council being the determining authority will assess the DA based on its merits.

All DA’s involving coastal protection works must be developed in accordance with local planning and environmental legislation including the Coastal Management Act and Coastal Management State Environmental Planning Policy. Designs must be developed by a coastal engineer.
 

How long would any proposed (seawall and nourishment) solution last?

The life of any structure would be determined through a detailed design process, the current MHL studies are concept designs. Seawalls on open coast environments, like Wamberal Beach, typically have an initial design life of 50 years. However, many seawalls on the Australian open coast are over 100 years old.

Sand nourishment is central to the long-term solution being investigated. Wamberal Beach is relatively stable. Therefore, any sand added to the beach system through nourishment will remain within the natural system for some time (although it may move back and forth between the dunes, beach and surfzone). 

The life span of the proposed program of works will be designed to consider future climate change (i.e. sea level rise). The program of works would be delivered to appropriate coastal engineering standards.
 

Is Council progressing any of the options to detailed design?

No, detailed design will be requirement of any Development Application lodged. 

Council are responsible for assessing the privately submitted development applications against the Minimum Engineering Guidelines, Coastal Management Act 2016 and Coastal Management SEPP 2018. 
 

Is Council developing a funding model for the construction of a Terminal Protection Structure (seawall)? 

No, the development of a funding model will be a requirement of any Development Application lodged and it will be assessed as part of the development application process. 

What are the next steps for the Wamberal project?

Review of the Manly Hydraulics Laboratory’s (MHL’s) technical studies, results from the community consultation and consideration of Councils role in relation to coastal erosion have highlighted specific criteria for a preferred seawall design which include that:

  • The asset to be located as far landward as possible, to reduce interaction with coastal processes and maximise beach width
  • It will be located wholly on private property where possible
  • The asset to be constructed, owned and maintained by property owners 
  • The Seawall to have the narrowest footprint, to reduce erosion/beach encroachment)
  • It will have the least sand nourishment requirements, both upfront and during the maintenance phase

While these criteria highlight options 3 and 4, which are vertical seawalls, as the preferred designs similar designs that meet the same criteria may be acceptable.

Council is now in the process of engaging coastal engineers to develop Minimum Engineering Guidelines which will identify specific criteria to guide coastal protection development applications at Wamberal Beach. These guidelines will be used by Council in conjunction with the Coastal Management Act 2016 and Coastal Management SEPP 2018 when assessing development applications.
 

Public exhibition

Public exhibition

Draft Wamberal Beach Terminal Protection Structure Engineering Design Requirements

Council engaged Manly Hydraulics Laboratory to draft the Wamberal Beach Terminal Protection Structure Engineering Design Requirements which outline specific criteria for assessment of Wamberal Beach coastal protection development applications. 

These Design Requirements outline engineering specifications and details such as the alignment, length of construction, material selection, landscaping, and maintenance requirements.  These requirements reflect what the community said was of value and importance during the community consultation period.

This milestone follows on from the completion of extensive community consultation, and expert technical studies to identify an effective and viable long-term solution to beach erosion at Wamberal Beach.  

Once adopted these requirements will be used in conjunction with the Environmental Planning and Assessment Act 1979, Coastal Management Act 2016 and Resilience and Hazards SEPP 2018 during development application assessments.

Have your say

Council is performing its regulatory function as a Local Government to develop planning controls which will enable Wamberal foreshore property owners to undertake approved development to protect their assets whilst the beach public amenity and environment is protected appropriately.

The community is invited to: 

Submissions are to be addressed to the Chief Executive Officer, Mr David Farmer between 29 June and 27 July 2022 via: 

The Draft Design Requirements note that any development application for a section of seawall at Wamberal Beach will be subject to public exhibition, providing the public with additional opportunities to comment on the detailed design drawings, environmental impact assessments, construction programs and maintenance plans.

When providing feedback to Council your attention is drawn to the provisions of the Government Information (Public Access) Act 2009 which allows for possible access to certain public and personal documentation. View our privacy statement.

Further information on the Wamberal Beach Terminal Protection and Sand Nourishment – Investigation and Concept Design is available in the introduction, community consultation and technical studies tabs at the top of this page. 
 

Why did Council develop Design Requirements for terminal protection structures (seawalls) and Sand Nourishment at Wamberal Beach? 

Council has drafted Design Requirements which outline specific criteria for the assessment of Wamberal Beach coastal protection development applications. 

Once adopted these guidelines will be used in conjunction with the Coastal Management Act 2016 and Resilience and Hazards SEPP 2018 during development application assessments.

These Design Requirements outline engineering specifications and details such as the minimum footprint, length of construction, material selection, landscaping, and maintenance requirements.  These guidelines reflect what the community said was of value and importance during the community consultation period.
 

What are the key design requirements identified in the draft Wamberal Beach Terminal Protection Structure Engineering Design Requirements? 

  1. Guidelines for preferred concept design – alignment of seawall – concept design and alignment drawings, site specific geotechnical requirements and shadow modelling design criteria, including guidelines for design life including future modifications
  2. List relevant legislation 
  3. Guidelines for contamination assessment and remediation and reuse of removed material
  4. Guidelines for terminal end controls during and post construction, beach access points and beach safety during construction and other environmental aspects.
  5. Guidelines for construction impacts 
  6. Guidelines for construction schedule 
  7. Guidelines for landscaping and aesthetics 
  8. Guidelines for certification 
  9. Guidelines for seawall maintenance and ongoing responsibility and security

Will the community be able to have a say when development applications for terminal protection at Wamberal Beach are submitted? 

Yes. The Draft Design Requirements note that any development application for a section of seawall at Wamberal Beach will be subject to public exhibition, providing the public with additional opportunities to comment on the detailed design drawings, environmental impact assessments, construction programs and maintenance plans.

Will the Wamberal Seawall Advisory Taskforce still operate? 

Yes. The Taskforce Terms of Reference were recently revised to provide a focus on sand nourishment. Council will continue to work closely with the NSW Government, through the Wamberal Seawall Advisory Taskforce, to implement a sustainable long-term solution to the coastal erosion issues on Wamberal Beach.

What information was used to inform the development of the draft Design Requirements? 

Council has been working with Manly Hydraulics Laboratory (MHL), property owners, the Wamberal Seawall Advisory Taskforce and the broader Central Coast community to understand how to achieve a long-term solution to coastal erosion at Wamberal Beach. 

The draft Design Requirements reflect the findings of the MHL Wamberal Terminal Protection and Sand Nourishment technical studies. The $498,996 project was 50:50 funded by NSW Government through the NSW Coastal and Estuaries Grants Program.

The draft Design Requirements support a solution, based on the feedback received from the community and expert engineering advise, to maximise both the amenity of the public beach and the net present value (NPV) for a coastal protection seawall at Wamberal Beach.
 

How can I find out more information on the draft Design Requirements? 

For more information on the draft Design Requirements, you can: 

How can I have my say on the draft Design Requirements? 

Council is encouraging the community to provide feedback on the draft Design Requirements. 
Between 29 June and 27 July 2022 the community are invited to: 

What are the next steps for the draft Design Requirements? 

Following this public exhibition period, the final Design Requirements will be presented to Council for adoption and then used in conjunction with the Environmental Planning and Assessment Act 1979, Coastal Management Act 2016 and Resilience and Hazards SEPP 2021 during development application assessments.

Where's it happening?

Wamberal Beach, New South Wales 2260, Australia

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