MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2021
CONTENTS 3 PART A
What is the Marks Point and Belmont South Foreshore Management Plan?
3 Why we need a Foreshore Management Plan
4 Area covered by the Plan 5 Foreshore values and current state of the foreshore 5 How does this Plan link to the Marks Point and Belmont South Local Adaptation Plan?
41 GLOSSARY ? GLOSSARY 42 REFERENCES AND RESOURCES 43 APPENDIX 1: Seagrass assessment summary 48 APPENDIX 2: Areas sensitive to Aboriginal heritage
6 How to read this Plan
8 PART B
How the Plan was prepared 8 Community involvement 9 Assessing and prioritising foreshore areas 11 Prioritisation map 12 Developing conceptual designs 13 Legislation and policy frameworks
14 PART C
Key elements of the Plan
The following documents accompany the Plan and sit separately:
TOOLKIT – How to implement foreshore treatments
CASE STUDIES – three case studies on local
16 Foreshore treatment design options
foreshore treatments
38 Guiding principles
DESCRIPTION OF THE AREA – background
40 Recommendations
on Marks Point and Belmont South
These documents can be found on shape.lakemac.com.au/adapting-marks-pointbelmont-south
ACKNOWLEDGEMENT OF COUNTRY The City Council of Lake Macquarie acknowledge the Aboriginal people known today as the Awabakal, as the traditional Custodians of the land, respecting Aboriginal Elders past, present and future. Lake Macquarie City Council recognise the local Aboriginal community today in all of their diversity, who came forward to share their experiences, knowledge, images and memories.
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LAKE MACQUARIE CITY COUNCIL
WHY WE NEED A FORESHORE MANAGEMENT PLAN FOR Marks Point and Belmont South The Marks Point and Belmont South Foreshore Management Plan (FMP) provides practical information to help local residents and Council plan and implement foreshore management works, protecting the area now and into the future. The Plan aims to simplify, and where possible streamline, the planning, design and approval process.
The purpose of the FMP is to provide design guidelines to address the current issues with the foreshore while ensuring, where feasible, that works are consistent with the eventual requirements of the foreshore revetment required in the Marks Point Belmont South Local Adaptation Plan (LAP). The FMP includes solutions to key issues identified by Council and the community such as foreshore erosion and tidal inundation, public amenity and foreshore access.
This Plan was co-designed by a joint Community and Council Working Group consisting of local resident volunteers and Council staff. The Working Group ensured that important community values, such as water recreation access, aesthetics and foreshore walking access, were account for when preparing the FMP.
The joint Community and Council Working Group created a vision for the FMP that includes seven key principles: Safe walking access as wide as possible along the public foreshore in locations currently used by the public
Adaptive design
in response to triggers outlined in the Marks Point Belmont South LAP (facilitates future adaptation)
Protect the public
foreshore and properties from erosion
Protection from inundation
associated with projected sea level rise and wave-overtopping
Aesthetically pleasing Ease of maintenance
including management of accumulated seagrass wrack
Clear guidance
to assist Council and the community when planning foreshore stabilisation projects
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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AREA COVERED by the Plan
Marks Point and Belmont South are two low-lying, neighbouring suburbs on the eastern side of Lake Macquarie, formed on a sand bar in between the lake and the coast. The suburbs are home to about 3,000 Lake Macquarie residents (2018) with many properties in the area enjoying waterfront views and access to the lake foreshore. The Foreshore Management Plan focuses on six kilometres of lake foreshore in the Marks Point and Belmont South suburbs. The area in the Plan extends from Lake Macquarie Yacht Club at Belmont South to the southern end of Swan Bay at Marks Point (Figure 1). Residential properties dominate the foreshore in the area, and recreational structures such as jetties, boat ramps, and slipways commonly occur along the shoreline.
Figure 1. Aerial image showing the extent covered in the FMP. Insert: Location of Marks Point and Belmont South in Lake Macquarie.
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LAKE MACQUARIE CITY COUNCIL Generated by: LakeMaps
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303 Meters
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A4. Foreshore values and current state of the foreshore A4. Foreshore values and current state of the foreshore
FORESHORE VALUES
A key motivation for preparing the plan was the current condition of the A key motivation for preparing the plan was the current condition of the varies considerably in terms of stability, amenity and condition of existi varies considerably in terms of stability, amenity and condition of existin measures. The foreshore consists of a mix of exposed and eroded land, measures. The foreshore consists of a mix of exposed and eroded land, ad designs, areas of public or private foreshore rehabilitation and minimal designs, areas of public or private foreshore rehabilitation and minimal se and well‐vegetated naturally sloping foreshores. and well‐vegetated naturally sloping foreshores.
and current state of the foreshore A key motivation for preparing the plan was the existing condition of the lake foreshore. Currently, the foreshore contains a mix of exposed and eroded land, ad-hoc vertical seawall designs, and a few sections with stable and well-vegetated naturally sloping foreshores. Local residents report increasing erosion in exposed areas, witnessing parts of the foreshore progressively recede over recent years. In some areas, headwalls from stormwater pipe outlets along the nearshore are now extending up to five metres into the water from the eroding foreshore.
Photos show current conditions along some sections of foreshore
Local residents have reported an increasing rate of erosion in exposed a Local residents have reported an increasing rate of erosion in exposed are the foreshore progressively recede over the recent years. Headwalls fro the foreshore progressively recede over the recent years. Headwalls from HERE'S WHAT WE HEARD: outlets along the nearshore are now extending up to 5 metres into the w outlets along the nearshore are now extending up to 5 metres into the w foreshore. foreshore. 'The foreshore should be protected from further erosion, properly drained Some residents have reported witnessing lake level rise first‐hand, shari Some residents have reported witnessing lake level rise first‐hand, sharin and contoured for ease of wrack removal.'sandy beaches spreading into the water, and wave overtopping becoming sandy beaches spreading into the water, and wave overtopping becomin
'I value a safe, wide and well drained pathway around the foreshore, suitable to A5. How to read this Plan A5. How to read this Plan enable future raising and protecting with a revetment to combat sea level rise.'
The plan has been structured around four main parts and includes an ap The plan has been structured around four main parts and includes an app
'This improved foreshore also should haveadditional resources to assist Council and the community. ease of access in and out of the water for additional resources to assist Council and the community. public use and appeal.'
Part A – Contains the background to the plan, what it aims to achieve, w Part A – Contains the background to the plan, what it aims to achieve, wh areas it covers. This part also summarises the unique values and attribu areas it covers. This part also summarises the unique values and attribut why Council and the Community want to protect and enhance it. This is why Council and the Community want to protect and enhance it. This is a readers wanting to know how the plan might benefit them. readers wanting to know how the plan might benefit them.
HOW DOES THIS PLAN
Part B – Describes how the plan was prepared with a focus on the comm Part B – Describes how the plan was prepared with a focus on the commu collaborating to identify the values and a vision for the area, identifying collaborating to identify the values and a vision for the area, identifying t framework, key site attributes, a prioritisation matrix to help Council sta framework, key site attributes, a prioritisation matrix to help Council staf protect the foreshore. protect the foreshore.
link to the Marks Point Belmont South Local Adaptation Plan?Part C – Contains the key elements of the plan arising from the legal and Part C – Contains the key elements of the plan arising from the legal and The Marks Point and Belmont South Local Adaptation Plan (LAP) 2016 was codesigned with local residents to plan long-term strategies in response to changing lake and flood levels. The Foreshore Management Plan (FMP) was an action identified in the LAP to address current foreshore erosion issues and provide long-term considerations so designs can be adapted in future to rising lake levels. Foreshore treatments need to be consistent with the eventual requirement in the LAP, which identifies a projected 0.9m lake level rise by 2100.
analysis and prioritisation. It also presents concept designs and guiding analysis and prioritisation. It also presents concept designs and guiding p Council and local residents might undertake foreshore protection works Council and local residents might undertake foreshore protection works i
A key design principle in the LAP is to raise the Part D – Provides more detailed information and a more practical ‘toolk Part D – Provides more detailed information and a more practical ‘toolkit land surface in stages, so that foreshore crest residents to plan, design, construct and maintain sustainable foreshore residents to plan, design, construct and maintain sustainable foreshore a level is always at least 0.5m above the lake future. This part will assist Council and the community to focus on spec future. This part will assist Council and the community to focus on specif surface. Currently, the nominal lake surface is 0.1m on the Australian Height Datum (AHD) sea level and the nominal foreshore level is 0.6m AHD. The lake level is expected to rise in future in line with sea level rise projections. For this reason, it’s important that the LAP and FMP relate or ‘talk to’ each other.
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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HOW TO
read this Plan THIS MAIN VOLUME OF THE PLAN INCLUDES
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PART A
PART B
PART C
Background to the Plan, what it aims to achieve, who it can assist and what areas it covers. This part also summarises the unique values and attributes of the foreshore and why Council and the community want to protect and enhance it. This is a good starting point for readers wanting to know how the Plan might benefit them.
How the Plan was prepared through community and Council collaboration to identify the values and a vision for the area, the legal and planning framework, key site attributes, and a a prioritisation matrix to help Council and local residents protect the foreshore.
Key elements of the plan arising from the legal and planning review, site analysis and prioritisation. It also presents concept designs and guiding principles to inform how Council and local residents might undertake foreshore protection works in the area.
APPENDIX 1
APPENDIX 2
A summary of the broadscale seagrass assessment completed during the preparation of the Plan. This can be a referenced when planning foreshore treatments.
A map indicating broad areas that may be sensitive to Aboriginal heritage, following an archaeological report. This can be referenced in Development Applications to indicate if the foreshore treatment is or is not located within a sensitive area.
LAKE MACQUARIE CITY COUNCIL
ADDITIONAL SECTIONS SUPPORTING THE PLAN INCLUDE TOOLKIT
DESCRIPTION OF THE AREA
Provided in a separate document, the toolkit provides more detailed information and a more practical ‘toolkit’ to enable Council and residents to plan, design, construct and maintain sustainable foreshore areas now and into the future. This part will assist Council and the community to focus on specifics of appropriate foreshore treatments at a site-specific level, prepare development applications and provide a guide when applying for required permits.
A separate short document providing background on the social and natural environment of the Marks Point and Belmont South foreshore area.
CASE STUDIES To accompany the Plan, three Case Studies focusing on local foreshore treatments have been included to show the steps involved when implementing foreshore stabilisation works. • C ase Study - Emily Street, Marks Point Foreshore Pilot Stage 1 • C ase Study - Emily Street, Marks Point Foreshore Pilot Stage 2 • C ase Study - Bowman Street Foreshore Stabilisation, Swansea
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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PART B
N A L P E HOW THEPARED WAS PR
COMMUNITY INVOLVEMENT
The Foreshore Management Plan grew out of the collaborative efforts of a joint Community and Council Working Group consisting of local residents living in the Marks Point and Belmont South suburbs and Council staff. The continuous involvement of the local representatives provided strong community ties to the project and an invaluable amount of knowledge, perspectives and strategic input.
Over a 24 month period, discussions and site visits by the Working Group informed the framework, objectives and actions of the Foreshore Management Plan.
Key steps taken by the Working Group:
Communication and engagement plan
Review the purpose of the Plan
Review legislative and policy requirements
Develop conceptual foreshore designs
Create criteria to prioritise foreshore sections
Collect information by desktop analysis and site visits
Independant Coastal Engineer review
Internal and external stakeholder review of the draft Plan
Present draft Plan to wider community for feedback
Adopt and Implement Marks Point and Belmont South Foreshore Management Plan
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LAKE MACQUARIE CITY COUNCIL
ASSESSING
and prioritising foreshore areas The joint Community and Council Working Group inspected the foreshore to identify factors that would influence the foreshore treatment designs.
Aspects recorded included: • t ype and condition of current foreshore protection structures (public and private), • p resence and condition of public assets and recreation areas,
The Working Group identified the extent of active erosion, the width of land from shoreline to property boundaries, and public safety hazards as the three most significant risks that should guide the prioritisation of foreshore works.
• seagrass wrack build-up areas, • foreshore walking access, • a vailable land width for potential protection works, and • p ublic safety hazards, such as exposed materials or scarps caused by erosion.
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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Low Priority sites are:
Moderate Priority sites are:
Stable (not eroding)
Falling outside of ‘High’ or ‘Low’ definitions
Adequate land width (>3m) Poses an acceptable public safety hazard
May contain one or two primary risk factors
The key criteria were applied to the entire foreshore to categorise each section as high, moderate, or low priority in terms of the need for treatment. The prioritisation matrix informed design briefs and mapping to assist Council staff and the community to visualise the condition and priority status of most sections of the foreshore. Figure 2 presents the prioritisation of the foreshore into high, moderate and low categories based on the Working Group's assessment.
High Priority sites are: Actively eroding Inadequate land width (<2-3m) Poses a current public safety hazard
AREAS NOT COVERED BY THE PLAN The Lake Macquarie Yacht Club and Belmont Pines Caravan Park have not been allocated designs under the Foreshore Management Plan as these areas have existing foreshore treatments in place. Marks Point Reserve and Naru Reserve have not been allocated designs under the Plan because of their potential ability to adjust naturally to changing conditions. They will be monitored over time to assess the impact of ongoing natural changes.
Council has a strong safety culture. Foreshore areas are dynamic systems that continually change over time. If you come across a section of foreshore that is dangerous or poses a risk to the public, please report this to Council’s Customer Service Centre on 4921 0333 or at council@lakemac.nsw.gov.au.
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LAKE MACQUARIE CITY COUNCIL
PRIORITISATION MAP The following Prioritisation Map was produced by applying the High, Moderate and Low priority criteria during foreshore inspections carried out by the joint Community and Council Working Group (Figure 2). It is anticipated that this map will be used as an aid to support Council and the community in considering the need for foreshore remediation works to be undertaken.
Figure 2. Prioritisation of foreshore into high, moderate and low categories following selection criteria
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An independent Coastal Engineer was involved in the process of preparing the for the FMP. The Peer Review report assessed the treatment options and wher designs would be appropriate depending on environmental constraints.
Not a concrete solution…
While were once a common practice to stabilise the foresh Notseawalls a concrete solution… structures are no longer a preferred treatment. Over time seawalls h While seawalls once a common practice to stabiliseimpacts. the foreshore, understood to be were associated with a range of negative Verti structures no longer a preferred treatment. Over seawalls absorb waveare energy leading to the transference oftime erosion ontohave nei understood to be associated with a range of negative impacts. Vertical d During the construction of seawalls, the removal of vegetation, mod absorb wave energy leading to the transference of erosion onto neighbo shoreline and poor structural permanently th During profiles, the construction of seawalls, thedesign removal of vegetation,change modificat the shoreline shorelineprofiles, and remove the natural buffering systems that absorb and poor structural design permanently change the na
DEVELOPING conceptual designs
the shoreline and remove the natural buffering systems that absorb wav
Working Group members engaged Council's City Projects department to develop preliminary foreshore treatment design concepts. KEY CONSIDERATIONS INCLUDED:
An independent Coastal Engineer was involved in the process of preparing the conceptual designs for the FMP. The Peer Review report assessed the treatment options and where different types of designs would be appropriate depending on environmental constraints.
• T reatment options need to comply with Not a concrete solution… legislative requirements designed to protect While seawalls were onceMany of the seawalls in Marks Point and Belmont Souths are showing signs of a common practice to stabilise the foreshore, these ‘hard’ health, safety and the environment. structures are no longer awalls, scouring behind walls, degraded structures, and exposed materials are c preferred treatment. Over time seawalls have been increasingly Many of the seawalls in Marks Point and Belmont Souths are showing sign understood to be associated with a range of negative impacts. Vertical designs are unable to Vertical seawalls further provide no escape for wrack to wash out of the water absorb wave energy walls, scouring behind walls, degraded structures, and exposed materials leading to the transference of erosion onto neighbouring properties. • ‘Soft’ treatments such as sloping beaches and While seawalls were once a common practice During the construction ofin anaerobic conditions which has led to a significant community issue in the a seawalls, the removal of vegetation, modifications made to Vertical seawalls further provide no escape for wrack to wash out of the w revetments are favourable. ‘Hard’, permanent shoreline profiles, andtopoor structuralthe design permanently change the natural landscape of stabilise foreshore, these ‘hard’ in anaerobic conditions which has led to a significant community issue in Some areas may be restricted to the use of seawalls the shoreline the natural buffering systems that absorb wave energy. treatments such as habitat-friendly seawalls mayand remove structures are no longer a preferred treatment. due to limited land available, foreshore slopes and be considered in limited areas. Vertical seawalls are unable to absorb wave Some areas may be restricted to the use of seawalls
NOT A CONCRETE SOLUTION
exposure to weather processes. Where seawalls may
• •
• • •
• •
• •
be approved, the treatment need to consider the due to limited land available, foreshore slopes and energy and can permanently change the Consider local drainage structures and seagrass alignment of the foreshore, how to minimise exposure to weather processes. Where seawalls may natural shoreline. They provide no escape wrack build-up areas. potential impacts on neighbouring foreshores, and be approved, the treatment need to consider the for how to include environmentally beneficial features. seagrass wrack to wash out of the water, alignment of the foreshore, how to minimise leaving it trapped and rotting which has led Prevent active erosion, dissipate wave energy, The ‘Environmentally Friendly Seawalls’ guide is potential impacts on neighbouring foreshores, and available publicly online to provide ideas on how to to a significant community issue in the area and limit wave overtopping landward of the how to include environmentally beneficial features. improve the environmental value of seawalls structure. [9] The ‘Environmentally Friendly Seawalls’ guide is seawalls in Marks Point and (pictured right). Many of the ad-hoc available publicly online to provide ideas on how to Belmont South are showing signs of failure, Increase biodiversity and environmental values. improve the environmental value of seawalls with slumping [9]walls and scouring behind walls (pictured right). Allow water access and recreational use of the commonly seen. In constrained areas where foreshore. seawalls may be the only viable option, the design needs to consider the alignment of the foreshore, Consider coastal design principles including Many of the seawalls in Marks Point and Belmont Souths are showing signs of failure. Slumping how to minimise impacts on neighbouring fetch, wave height, and how to minimise impacts walls, scouring behind walls, degraded structures, and exposed materials are commonly seen. foreshores, and include environmentally Vertical seawalls further provide no escape for wrack to wash out of the water, leaving it trapped on adjoining properties. in anaerobic conditions which has led to a significant community issue in the area. beneficial features. The ‘Environmentally Friendly Seawalls’ guide is Consistent with requirements in the Marks Point Some areas may be restricted to the use of seawalls available publicly due to limited land available, foreshore slopes and Belmont South LAP. exposure to weather processes. Where seawalls may online to provide Foreshore works should be triggered bybe approved, the treatment need to consider the ideas on how alignment of the foreshore, how to minimise environmental change or events ratherpotential impacts on neighbouring foreshores, and than to improve the how to include environmentally beneficial features. specific timelines. environmental value The ‘Environmentally Friendly Seawalls’ guide is of seawalls (see available publicly online to provide ideas on how to Maintain the natural alignment of the foreshore. improve the environmental value of seawalls references section). (pictured right). [9] Consider the asset life and maintenance of treatments.
• C onsider potential land reclamation in areas of limited land widths or evidence of erosion scarps.
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LEGISLATION
and policy frameworks The following table provides a high-level overview of legislation and policies that are relevant in preparing and implementing the Foreshore Management Plan (and undertaking works on the foreshore).
This table may look onerous at first; however a key purpose of the Plan is to help navigate and simplify the regulatory and approval processes. For further information on legislation, plans and policies visit Council’s website and/or legal information resources such as AustLII (www.austlii.edu.au)
LEGISLATION
STATE AND LOCAL PLANS AND POLICIES
Coastal Management Act 2016
State Environmental Planning Policy (Coastal Management) 2018 (Coastal SEPP)
Crown Land Management Act 2016
Marine Estate Management Strategy 2018-2028
Marine Estate Management Act 2014
Crown Land Management Regulation 2018
Environment Protection and Biodiversity Conservation Act 1999
Marks Point and Belmont South Local Adaptation Plan 2016
Fisheries Management Act 1994
Lake Macquarie Coastal Zone Management Plan 2015-2023
Local Government Act 1993
Lake Macquarie Local Environmental Plan 2014 (LMLEP 2014)
Environmental Planning and Assessment Act 1979
Lake Macquarie Development Control Plan 2014 (LMDCP 2014)
Heritage Act 1977
Lake Macquarie Foreshore Stabilisation and Rehabilitation Guideline 2013 (under review)
Protection of the Environment Operations Act 1997 No 156
NSW Fisheries Policy and guidelines for fish habitat conservation and management 2013
National Parks and Wildlife Act 1974
Imagine Lake Mac 2050 and Beyond 2020
Aboriginal Land Rights Act 1983
Lake Macquarie Aboriginal Heritage Management Strategy 2011 Environmentally friendly seawalls: A guide to improving the environmental value of friendly seawalls and seawall-lined foreshores in estuaries 2009 State Environmental Planning Policy (Infrastructure 2007) (Infrastructure SEPP) Local Government (General) Regulation 2005
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PART C
S T N E M E KEY EL PLAN OF THE
THE KEY OUTPUTS OR ELEMENTS OF THIS FMP INCLUDE: • The prioritisation matrix and map (outlined earlier in Part B – Figure 2) • A set of five potential concept designs to consider a useful basis for potential treatment options that might be applied to stretches of foreshore between Belmont South and Marks Point. • T he foreshore map (Figure 3 below) providing an overlay of the five concept treatment designs ie: where they might be suitable for application along the various sections of the Marks Point Belmont South foreshore • Detailed drawings (plan, elevation and photo-overlay) of each of the five concept designs • A set of guiding principles and recommendations to assist with designing, planning (including approval) and constructing suitable foreshore designs.
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Concept design name
Page number with concept drawing and details
Description
Application
Comments
Indicative cost estimate ($/linear meter) #
Design 1 - Sand Trapping Rock Fillets
18-21
A mix of ‘informal’ hard engineered and natural systems. Sand or pebble beach allowing easy foreshore access. Interspersed with rock fillets (mini groynes) to reduce erosion. Native planting to mimic natural systems.
Suited to gentler sloping foreshore areas with reasonable width to allow current public access and room for adaptation
+ wave dissipation + wrack breakdown + biodiversity + access + l ower construction cost to construct, maintain depending on site characteristics. +e ase of adaptation to rising lake levels - potentially more susceptible to storm event damage. Monitoring and maintenance essential.
$150-$300
Design 2 Saltmarsh & Sandstone Boulders
22-25
A mix of ‘informal’ engineered and natural systems. Sand or pebble beach allowing easy foreshore access. interspersed with boulder outcrops (mini groynes) to reduce erosion and provide secure foundation for native planting of saltmarsh to mimic natural systems.
Suited to gentler sloping foreshore areas with reasonable width to allow current public access and room for adaptation
+ wave dissipation + wrack breakdown + biodiversity + lower construction cost + access
$50-$100
LAKE MACQUARIE CITY COUNCIL
Concept design name
Page number with concept drawing and details
Description
Application
Comments
Indicative cost estimate ($/linear meter) #
Design 3 Sandstone Block & Boulder
26-29
A mix of hard engineered and natural elements. Providing formal edge to foreshore land and lake edge. Preferable alternative to vertical seawall. Provides for formal lake access and drainage integration
uited to steep, S actively eroding foreshore with narrow access Can be designed to manage high wave impact
+ wave dissipation + wrack breakdown + Biodiversity + Access + r easonable cost to construct, maintain depending on site characteristics. +e ase of adaptation to rising lake levels - Tends toward hard engineered rather than natural treatment
$300-$600
Design 4 Deck & Revetment
30-33
Construction of engineered rock revetment with deck – requires detailed engineering on pier footing and drainage
uited to steep, S actively eroding foreshore with narrow access
+ wave dissipation
$2500-$3500
Mangrove Seawall
34-37
Natural colonisation of the foreshore and/ or planting of native species to provide vegetated lake edge
an be designed C to manage high wave impact Deck and revetment can be raised with rising lake levels Primarily suited for areas where public access between the foreshore and the lake is limited and/or not required
+ wrack breakdown + Sun permeability + Biodiversity + Access - Expensive to construct, maintain and potentially adapt - Hard engineered rather than natural treatment + mimics natural systems
$50-$100
+ biodiversity + water quality + r easonable cost to construct and maintain depending on site characteristics - access may be limited
# Costs above are indicative costs for material only per linear meter of foreshore treatment. They are based on widths shown in the drawings. Final costs will vary considerably based on a site-by-site basis. Costs are for initial construction only and do not include ongoing maintenance and/or future modification in response to projected lake level rise. No allowance has been made for working in locations where access is difficult.
Labour has not been included. Design, engineering and approval costs have not been included and may vary considerably from site to site.
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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FORESHORE TREATMENT Design options
LAKE MACQUARIE CLUB After being reviewedYACHT by an independent Coastal Engineer, Council's City Projects team finalised five foreshore treatment designs for the Plan, found on the following pages. The following map indicates appropriate design options for each foreshore area depending on environmental ANDERSONS POINT constraints (Figure 3). The foreshore treatment designs provided in the Plan can be tailored to individual sites by qualified engineers undertaking the design.
LEGEND DESIGN 1 - SAND TRAPPING ROCK FILLETS SEAWALL DESIGN 2 - SALTMARSH & SANDSTONE BOULDER SEAWALL DESIGN 3 - SANDSTONE BLOCK & BOULDER SEAWALL DESIGN 4 - DECK AND REVETMENT SEAWALL DESIGN 5 - MANGROVE SEAWALL AREA EXCLUDED FROM PLAN RECENTLY COMPLETED WORKS, EXCLUDED FROM PLAN
CANE POINT
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LAKE MACQUARIE CITY COUNCIL COST ESTIMATE Deck and Revetment Seawall
$2,500 - $3,500
LAKE MACQUARIE YACHT CLUB Design 1 - Sand Trapping Rock Fillets Design 2 - Saltmarsh & Sandstone Boulders
ANDERSONS POINT Design 4 - Deck & Revetment Design 5 - Mangrove Sea Wall
Recently completed works, excluded from plan
CANE POINT
Design 1 - Sand Trapping Rock Fillets Design 2 - Saltmarsh & Sandstone Boulders
VILLAGE BAY
Design 2 - Saltmarsh & Sandstone Boulders Design 3 - Sandstone Block & Boulder Design 4 - Deck & Revetment (Only in partial segment)
Design 4 - Deck & Revetment Design 5 - Mangrove Sea Wall
SWAN BAY
Design 1 - Sand trapping rock fillets Design 2 - Saltmarsh & Sandstone Boulders Design 2 - Saltmarsh & Sandstone Boulders Design 3 - Sandstone Block & Boulder
Design 4 - Deck & Revetment Design 5 - Mangrove Sea Wall
Figure 3. Foreshore treatment design options map CITY PROJECTS - PUBLIC DOMAIN DESIGN 126 - 138 MAIN ROAD SPEERS POINT NSW 2284 TEL +61 2 4921 0333 WWW.LAKEMAC.COM.AU
PROJECT
DRAWING TITLE
Marks Point & Belmonth South Foreshore Design
Site Plan
Marks Point & Belmonth South Foreshore
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
DATE SCALE
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17 1:
Design 1 - Sand Trapping Rock Fillets (Elevation)
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LAKE MACQUARIE CITY COUNCIL
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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Design 1 - Sand Trapping Rock Fillets (Plan and A
PROPERTY
-4----,-------
◄--�---
Sand Trapping Rock Fillets - Plan Scale: 1 :50
LAKE CITY
MACQUARIE
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PROJECT
CITY PROJECTS • PUBLIC DOMAIN DESIGN 126 -138 MAIN ROAD SPEERS POINT NSW 2284 TEL +61 2 4921 0333 WWW.LAKEMAC.COM.AU
LAKE MACQUARIE CITY COUNCIL
Marks Point & Belmonth South Foreshore Design Marks Point & Belmonth South Foreshore
Adaptation)
LEGEND PR. PLANTING PR. TIMBER EDGE SS BOULDERS
Additonal sandstone boulders nominal size 600-900mm for adaptation.
Local native planting. Refer to ------------------- Foreshore Stabilisation and Rehabilitation Guidelines, Appendix one & two.
Revetment and groin. Sandstone ------------------- boulders nominal size 600-900mm.
2
Sand Trapping Rock Fillets - Adaptation Plan Scale: 1 :100
DRAWING TITLE
Sand Trapping Rock Fillets : Plan & Adaptation DATE SCALE
9/11/2020
AS SPECIFIED
DRAWN BY: CHECKED BY: APPROVED BY:
C.YOUS S.BERT D.WALT
DRAWING NO.
REVISION
L300
C
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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Design 2 - Saltmarsh & Sandstone Boulders (Elev
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vation)
MARKS POINT AND BELMONT SOUTH FORESHORE MANAGEMENT PLAN 2020
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Design 2 - Saltmarsh & Sandstone Boulders (Plan
-------
--
PROPERTY
--------
Saltmarsh and Sandstone Boulders - Plan Scale: 1 :50
LAKE CITY
MACQUARIE
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PROJECT
CITY PROJECTS -PUBLIC DOMAIN DESIGN 126 -138 MAIN ROAD SPEERS POINT NSW 2284 TEL +61 2 4921 0333 WWW.LAKEMAC.COM.AU
LAKE MACQUARIE CITY COUNCIL
Marks Point & Belmonth South Foreshore Design Marks Point & Belmonth South Foreshore
n and Adaptation)
LEGE D -
PR. SALTMARSH PLANTING SS BOULDERS
Local native saltmarsh planting. Refer to Foreshore Stabilisation ---- - - ------------ and Rehabilitation Guidelines, Appendix one and two.
Revetment. Sandstone boulders ------------------- nominal size 600-900mm.
Additonal sandstone boulders nominal size 600-900mm for adaptation.
------------------- Pebble or locally sourced sand.
2
Saltmarsh and Sandstone Boulders - Adaptation Scale: 1 :100
DRAWING TITLE
Saltmarsh & Sandstone Boulders - Plan & Adaptation DATE SCALE
9/11/2020
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DRAWN BY: CHECKED BY: APPROVED BY:
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Design 3 - Sandstone Block & Boulder
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Design 3 - Sandstone Block & Boulder (Plan and A
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Sandstone Block & Boulder Seawall - Plan
VARIES
Scale: 1 :50
LAKE CITY
MACQUARIE
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PROJECT
CITY PROJECTS -PUBLIC DOMAIN DESIGN 126 -138 MAIN ROAD SPEERS POINT NSW 2284 TEL +61 2 4921 0333 WWW.LAKEMAC.COM.AU
LAKE MACQUARIE CITY COUNCIL
Marks Point & Belmonth South Foreshore Design Marks Point & Belmonth South Foreshore
Adaptation)
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LEGEND PR. PLANTING PR. MULCH PR. RIVER
5-100mm washed river pebbles --------- - - - - - - -wrapped in Bidim A64 or approved equivalent.
PR. FRP DECK ---- --
EX. SEAWALL EXTENTS SS BOULDERS
Wheel sawn sandstone _________________ blocks/logs1000x500x500mm. Two sawn sides: top and bottom.
Local native planting. Refer to - - ------------ Foreshore Stabilisation and - Rehabilitation Guidelines, - - Appendix one and two.
Additonal sandstone boulders nominal size 600-900mm for adaptation.
Arrangement for jetty and boat ______________ ramp inclusions. Details to be provided in Foresh� G"ideliMs
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----------------- Diamond sawn sandstone steps 1000x300x150mm for lake access.
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----------------- Revetment. Sandstone boulders - nominal size 600-900mm.
Revetment to cover existing pebble or locally ---e-----�h sourced sand beach. Sandstone block to existing lake access.
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Sandstone Block & Boulder Seawall - Adaptation Plan Scale: 1 :100
DRAWING TITLE
Sandstone Block & Boulder Seawall Plan & Adaptation DATE SCALE
9/11/2020
AS SPECIFIED
DRAWN BY: CHECKED BY: APPROVED BY:
C.YOUS S.BERT D.WALT
DRAWING NO.
REVISION
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Design 4 - Deck & Revetment (Elevation)
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Design 4 - Deck & Revetment (Plan and Adaptatio
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on)
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Design 5 - Mangroves (Elevation)
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Design 5 - Mangroves (Plan and Adaptation)
Mangrove - Plan
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Mangrove - Adaptation
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GUIDING
When deciding on an appropriate foreshore treatment, a number of points need to be considered such as the location of the site, environmental surroundings, and legislative requirements. Assessing these considerations in the early stages could help you save time and money throughout the approval process.
principles
Once you have engaged a qualified engineer or designer, they should consider the guiding principles shown below; a checklist is provided in Appendix 3 to help with this process.
PRIORITY OF SITE
CONSTRUCTION, MAINTENANCE AND ADAPTATION
SITE LOCATION/ANALYSIS
Guiding principles
ENVIRONMENTAL CONSTRAINTS
STRUCTURE DESIGN
APPROVALS
FEASIBILITY
GUIDING principles checklist
PRIORITY OF SITE
(NEEDING FORESHORE STABILISATION) • Is the site a priority (High, Medium or Low) for Council, the community or both? • Do the measures need to take place immediately or in 0-2 years, 2-5 years, 5-10 years or 10+ years? • Does the site have existing foreshore treatments? Is it in good condition, have minor defects, or require maintenance to return to an acceptable level of service? • Is the natural alignment maintained in the site or do scarps and evidence of erosion disrupt the natural foreshore alignment?
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SITE LOCATION/ANALYSIS
FEASIBILITY
• W hat prominent wind and wave patterns will affect this site throughout the year?
• Are the proposed measures being undertaken for primarily public or private benefit?
• Is the foreshore on public (Council or Crownowned) or private land?
• How will the proposed measures be funded?
• What is the length and width of the area?
• Is the proposed design feasible to construct and maintain?
• W hat level of community engagement is required?
• Have all related costs been considered (e.g. development approval, maintenance)?
• W ill the treatment cause damage to neighbouring areas?
• Is the asset life of the treatment feasible?
• W hat infrastructure is currently found on site? • What types of soils are found on site?
ENVIRONMENTAL CONSIDERATIONS • What environmental constraints are present on the site?
APPROVALS
- IS THERE A RECOGNISED APPROVAL PATHWAY? • Are the proposed measures consistent with the objects of the Coastal Management Act 2016 and the Coastal State Environmental Planning Policy 2018?
• Does the proposed foreshore treatment increase environmental values, and how will negative environmental impacts be mitigated during construction?
• Are the proposed measures likely to gain approval by Department of Primary Industries (Fisheries) and Crown Land as per their policies and guidelines?
• Will measures damage seagrass or native vegetation?
• Do the proposed measures comply with the Lake Macquarie Development Control Plan 2014?
• Is the area sensitive to Aboriginal heritage?
• Do the proposed measures comply with Council's Foreshore Stabilisation and Rehabilitation Guidelines?
• Is the design based on natural systems rather than 'hard' engineering approaches?
STRUCTURE DESIGN • Does the proposed design address the three most significant risks: erosion, width of land from shoreline to property boundaries, and public safety? • Does the design take account of current lake levels and projected sea level rise? Has public safety, wave overtopping and inundation been taken into account? • Will the proposed design maintain surrounding amenity and visual aspects? • Will the design ensure that access to and the use of foreshore won’t be affected, and areas of constrained pedestrian access be improved where feasible?
• Are the proposed measures consistent with other legislation?
CONSTRUCTION, MAINTENANCE AND ADAPTATION • Can you easily access the site for construction? • Does the construction of the design have measures in place to manage direct and indirect risks? • What is the proposed asset life of the structure? • Can the treatment be easily adapted and raised over time? • What long-term maintenance will be required and who will undertake maintenance?
• Can the design be adapted in future to effectively manage changing environmental conditions? • Does the design require reclamation to restore a natural foreshore alignment?
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RECOMMENDATIONS For Council or community members wishing to implement foreshore treatment designs ahead of Council’s works program, the Plan and Council staff can provide advice and support to help simplify the process.
COUNCIL CAN SUPPORT YOU
HELPING WITH EXPENSES
• E xperienced Council staff can meet residents on-site and assist with selecting and discussing foreshore treatment designs
• T he Plan includes concept foreshore treatments designs that have been reviewed by an independent Coastal Engineer
• C ouncil’s Duty planner is available for information on foreshore treatment proposals
• C ouncil has conducted a broad-scale seagrass assessment and received an Archaeological report for the area to save costs for individual residents in the approval process
• C ouncil staff will work with the community to monitor the foreshore and trigger points e.g. changes in lake levels or asset condition.
SIMPLIFIED APPROVAL PROCESS • T he concept foreshore designs included in the Plan can be tailored by designers or engineer consultants to suit individual sites • T he Toolkit steps through the approval process for community members wishing to implement foreshore treatment designs
PUBLIC AREAS MANAGED BY COUNCIL • C ouncil will actively seek funding to stabilise or treat foreshores in high priority sites on public land • F oreshore remediation will be considered as part of Council’s 10, 4, and 1 year strategic and operational plans.
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• G rant opportunities for individual or community-based foreshore restoration projects may be available; contact Council to find out more about potential options
FREE WEBSITES TO HELP GATHER INFORMATION • C ouncil’s Property Enquiry tool shows conditions that apply to the land and permitted developments • N SW Department of Planning, Industry and Environments digital ePlanning Spatial Viewer can generate reports showing information and planning controls for selected properties • M ore useful resources can be found in the References section of the Plan
GLOSSARY Acceptable risk: a risk that is sufficiently low following an assessment of likelihood and consequence Accretion: the build-up of sediments to form land in the lake Adapt: ability to adjust to change Adaptive design: designs that can be modified over time in response to change Ambulatory: the movement of the foreshore landward or lakeward over time Anaerobic: without oxygen Asset life: the amount of time infrastructure will be effective for Australian Height Datum (AHD): similar meaning to the old measure ‘above sea level’ Erosion: the wearing away of land from natural forces such as waves and wind Fetch: the total distance of a surface that wind can blow continuously over, such as the lake, that can form wind waves Hard structures: includes revetments and seawalls that retain and armour the shoreline Hazard: A source of potential harm or a situation that may cause loss Lake level rise: a rise in water levels in the Lake associated with both heavy rain events and sea level rise Longshore drift: wave currents causing sediment to move along the shoreline Maladaptation: poor, failed or inadequate adaptation Nuisance flooding: the pooling of stormwater runoff in low-lying areas from poor drainage
Risk: chance of something happening that will have an impact Scarp: a change in the natural shoreline caused by water and/or wind erosion Seagrass wrack: dead seagrass leaves that builds up on the shore Sea level rise: a continuous rise in global sea levels as warm water expands and ice sheets and glaciers melt, relative to human-induced climate change Soft structures: includes beaches with coarse sand or pebble, and incorporates vegetation Storm surge: an increase in water levels caused by storm effect Tidal inundation: when daily lake tides cover the land Transference (of erosion): foreshore treatments that cause wave energy to be passed either side onto neighbouring properties Triggers or Trigger Points: An option or action based on agreed criteria when a particular time or event type point. Given the uncertainty in projected lake level rise it is difficult to assign a precise time trigger (ie. year). For this reason, event-based triggers are preferred along with careful monitoring and reporting to ensure Council and the community are aware when trigger points are approaching. Unacceptable risk: a risk with high likelihood and high consequence that requires actions to avoid or reduce the risk Wave over-topping: waves that wash over foreshore treatments onto the land
Reclamation: any works that involve placing material (e.g. sand, rocks) to fill the water
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REFERENCES AND RESOURCES BMT WBM. 2014. Foreshore Assessment of Shoreline Change and the Impact of Waves on Lake Macquarie
[1]
Lake Macquarie City Council. 2013. Foreshore Stabilisation and Rehabilitation Guidelines
[8]
Office of Environment & Heritage. 2012. Environmentally Friendly Seawalls: A guide to improving the environmental value of seawalls and seawall-lined foreshores in estuaries
[9]
Department of Primary Industries. 2013. Policy and Guidelines for Fish Habitat Conservation and Management (2013 update)
[2]
Insite Heritage PTY LTD. 2020. Aboriginal Archaeological Due Diligence Assessment
[3]
Lake Macquarie City Council. 2017. Citizen Science and Foreshore Inundation – Tidal Valves.
[4]
Lake Macquarie City Council. 2016. Marks Point and Belmont South Local Adaptation Plan Volume 1: Summary
[5]
Lake Macquarie City Council. 2016. Marks Point and Belmont South Local Adaptation Plan Volume 2: Full Local Adaptation Plan and other Appendices
[6]
Lake Macquarie City Council. 2014. Development Control Plans 2014
Salients. 2020. Marks Point / Belmont South Foreshore Master Plan – Foreshore Characterisation And Preliminary Consideration Of Feasible Treatment Concepts
[10]
Walpole, S., Parsons, J., & Jansson, J. 2004. “Carrying Many Small Stones” – A Story of Foreshore Stabilisation in Lake Macquarie
[11]
WBM Oceanic Australia. 2005. Removal of Organic Sediment and Beach Recreation, Village Bay, Lake Macquarie Review of Environmental Factors
[12]
WMA water. 2017. 2D Stormwater Modelling Study Marks Point and Belmont South
[13]
[7
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IPCC. 2019. The Ocean and Cryosphere in a Changing Climate
[14]
1 X I D N APPE SEAGRASS
assessment summary Introduction
Results
A seagrass assessment is required by authorities when implementing foreshore works. A broad-scale seagrass assessment was undertaken by Council to form a reference document in the Foreshore Management Plan. This will assist Council staff and land owners in the approval process when implementing foreshore treatments in Marks Point and Belmont South.
The results of the seagrass survey were divided into three zones (2m, 5m, 9m) measured from the shoreline into the lake. 2m (nearshore) zone The average seagrass cover in the 2m zone was 20.7%, consisting of Zostera (73.6%) and Halophila (26.4%) species. The average water depth in the 2m zone was 0.2m. The majority of sites contained a sandy or silty substrate (96%), with one site containing rocky substrate.
A summary of the broad-scale seagrass assessment is provided below. The full assessment can be found on ShapeLakeMac. The assessment identified seagrass species and their distribution, considered aquatic conditions along the nearshore, and outlined potential impacts when implementing foreshore treatments.
AVERAGE SEAGRASS COVER (%) PER 2M QUADRAT
20.7%
Seagrass cover
26.4%
Halophila cover
79.3%
No seagrass cover
73.6%
Zostera cover
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AVERAGE SEAGRASS COVER (%) PER 5M QUADRAT
57.6%
The average water depth for 9m quadrats was 0.5m. The majority of sites contained a sandy or silty substrate (91%), with one site recording ‘ooze’ due to the breakdown of organic matter and wrack on the lake bed.
51.6%
Halophila cover
No seagrass cover
5m zone Results in the 5m zone showed an average seagrass cover of 42.4%, consisting of Zostera (48.5%) and Halophila (51.6%) species. The average water depth at the 5m quadrats was 0.3m. Substrate at most sites consisted of sand and/or silt (96%). One site was recorded to contain ‘ooze’ due to the breakdown of organic matter and wrack on the lakebed.
AVERAGE SEAGRASS COVER (%) PER 9M QUADRAT
42.4%
Seagrass cover
48.5%
Zostera cover
9m zone Results for the 9m quadrat zone showed an average seagrass cover of 48.7%, consisting of Zostera (56.6%), Halophila (41.1%) and Ruppia (2.4%) species.
2.4%
Ruppia cover
51.3%
48.7%
Seagrass cover
No seagrass cover
41.1%
Halophila cover
56.6%
Zostera cover
Overall results
Most quadrats were found to contain patchy amounts of seagrass, with ‘denser’ seagrass beds located further away from the shoreline. The intertidal (nearshore) area predominantly contained no seagrass or had sparse individuals. The overall composition of seagrass cover was generally found to contain Zostera and Halophila species coexisting and mixed in with each other. No Posidonia australis or exotic species Caulerpa taxifolia was recorded during the survey.
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Assessment of potential impacts A summary of potential impacts and mitigation measures associated with seagrass communities and foreshore treatments is provided below. A range of common or likely impacts associated with implementing or maintaining foreshore treatments has been considered, as well as expected outcomes for a ‘no action’ scenario for comparison. The full assessment of potential impacts and mitigation measures can be viewed in the Seagrass Assessment document.
Barges – The use of work barges for construction may potentially impact seagrass communities if the vessel is within close proximity.
MITIGATION MEASURES • T o minimise potential impacts on seagrass the foreshore treatment should remain landward of the lake. In areas that are restricted by land width, the foreshore structures may need to be located partly within the intertidal zone. Compensation for damaging seagrass should be addressed by increasing the surrounding ecological values: - I rregular placing of materials in revetments
IMPLEMENTING FORESHORE TREATMENTS
- A ngled materials over flat-faced materials
The construction of foreshore treatments will result in short-term and potential long-term effects on the surrounding environment.
- E nhance habitat for terrestrial and aquatic species to encourage native flora and fauna to re-establish around the foreshore treatment.
POTENTIAL IMPACTS Disturbance or loss of seagrass – During construction, existing seagrass habitat in the nearshore area may be disturbed resulting in the loss or damage of habitat. Turbidity – Increased turbidity reduces the available light to seagrass and may affect associated fauna within the seagrass communities. Suspended sediment may be disturbed and relocated, causing the smothering of seagrass. Contamination – The construction of foreshore treatment works may expose contaminants such as Acid Sulfate Soils (ASS), black slag or organic sediments. The materials used in the foreshore treatment may also contain contaminants that could affect the natural environment.
- R evegetating areas - I ncorporating artificial habitual features
• T o reduce turbidity sediment control measures should be put in place prior to construction as per the NSW Office of Environment and Heritage guidelines ‘Managing Urban Stormwater: Soils and construction - Volume 1’. • T o reduce the introduction of contaminated materials, any materials or fill products are to be natural materials with no known contaminants. If contaminated soils are encountered during construction, works are to cease immediately and soils must be managed under Council’s Policy for Managing Contaminated or Potentially Contaminated Land.
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MAINTENANCE OF FORESHORE TREATMENTS – IMPACTS AND MITIGATION Maintenance of foreshore treatments is an essential consideration for long-term integrity of the structure.
- L awn clippings should be collected and placed in green waste bins, or directed away from waterways in larger scale areas.
NO ACTION – IMPACTS AND MITIGATION An absence of action in some areas will lead to a number of ongoing impacts on the foreshore area and seagrass communities.
POTENTIAL IMPACTS Maintenance of revegetated areas – Herbicide run-off or indirect spray may impact seagrass communities and affect water health via chemicals entering the water. Manual removal of exotics and mowing of lawns may lead to disturbance surrounding the structure, with waste by-products such as lawn clippings entering the lake and decreasing the water health. Larger scale repair may cause multiple impacts on seagrass communities (as covered above in ‘Implementing foreshore works – impacts and mitigation’).
MITIGATION MEASURES • I mpacts surrounding the maintenance of vegetation can be avoided by choosing appropriate controls; - U sing chemical spray in the area should be avoided; instead choose alternate techniques such as manual removal and weed suppression - R emoved weeds should be bagged and placed in green waste or landfill bins. - C are and caution should be taken when mowing areas to avoid damage to native species
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POTENTIAL IMPACTS Wrack accumulation – Due to a modified foreshore, the area has ongoing issues regarding wrack (dead seagrass). Wrack that cannot breakdown naturally forms black ‘ooze’ in the lake that can smother seagrass communities, cause changes in the chemical composition of waters, and reduce available light. Ad-hoc seawall structures – These structures negatively affect the environment as they are unable to absorb wave energy, leading to associated erosion on either side of the structure and a disturbed intertidal zone preventing seagrass to establish.
MITIGATION MEASURES • C hoose soft treatments and revetment-style designs are preferred over hard structures. • C onsider ‘end effects’ (erosion at the end of structures), and incorporate environmentally friendly options such as habitual features and revegetation techniques to increase biodiversity.
CONCLUSION A seagrass assessment was completed at a broadscale level that encompassed the extent of the Marks Point and Belmont South FMP. The intent of the seagrass assessment is to assist Council and community members in preparing Development Applications and applying for relevant permits when planning a suitable foreshore treatment in the area. The results were divided three into ‘zones’; 2m (nearshore), 5m zone, and 9m zone. The 2m (nearshore) zone will be most impacted from foreshore treatment works, and was found to contain on average low amounts of seagrass cover (20.7%) existing in patches or sparse distribution. Seagrass presence generally consisted of Zostera and Halophila species. No Posidonia australis or exotic Caulerpa taxifolia was recorded during the survey. No threatened species were recorded in the survey.
Potential impacts were investigated associated with the implementation and maintenance of foreshore treatments, which were deemed minimal with practical mitigation measures. These potential impacts were favourable when compared to the ‘no action’ scenario as large sections of the foreshore currently contains severe erosion, vertical seawalls, and the absence of seagrass communities within the intertidal area. As the recommended foreshore designs incorporate biodiversity values, an overall increase in ecological values is expected, including the potential re-establishment of seagrass communities in the intertidal area.
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2 X I D N E APP
AREAS SENSITIVE to Aboriginal heritage The purple polygons indicate areas that may be sensitive to Aboriginal heritage, following an archaeological report. This map can be referenced when submitting a Development Application to state if proposed foreshore treatments fall within or outside of a sensitive area. In some cases, additional studies may be required before commencing foreshore works.
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303 Meters
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Notes
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