3.1.3 Sediment transport and beach alignment · 2014. 11. 18. · Project 237236 File...

Project 237236 File 237236-RP-002-01-Kingfisher Parade Seawall-Detailed Design Report.docx 27 August 2013Revision 1 Page 8

3.1.3 Sediment transport and beach alignment The 2004 beach nourishment report models longshore sediment transport. Over the period 1977-2004 it was found that the net sediment transport is going West at a rate of 8,000m3/year under the influence of small waves. Only 30% of this transport occurs on the upper beach (70% of the transport occurs on the Beelbi Estuary flood shoal). During storms, the sediment transport is (briefly) reversed, and directed towards the east.

Shoreline stability The 2004 report indicated that the Kingfisher Parade upper beach dune width was narrowing by an average rate of 1m to 2m per year, while the dune width has increased by about 1m per year close to the Beelbi estuary, creating a sand-lobe. These shoreline changes have continued over 2004-2013, leading to the current erosion issue. This is well demonstrated by superposing of the shoreline survey of 2004 and 2013.

Cyclone erosion BPA evaluated the erosive action of a cyclone to be approximately 40m from the Beelbi Creek Estuary to Toogoom East. A 10m erosive episode, associated with a tropical cyclone, was recorded in February 1863.

3.2 Standard The preliminary design report includes an option analysis of possible coastal works which may mitigate on-going erosion at Toogoom. The consultation with stakeholder concludes that a rock revetment seawall is the most likely structure which may meet all necessary requirements to obtain a Development Approval for the project.

The minimum development standard for a seawall is 50 year design standard for a design life of 50 years. This follows the Department of Environment and Heritage minimum requirements for seawalls.

There is no specific standard provision for overtopping rate for seawalls as these structures are not designed to mitigate both erosion and flooding.

A coastal levee could be designed to mitigate the effect of coastal flooding. Typically, the averaged overtopping rate behind such a levee should be controlled under 1 l/m/s to reduce structural damage. At 200l/m/s is typically the rate a reinforced levee (with a paved promenade) can sustain, but this does not either protect personnel or structures from damage.


3.3 Alignment Appendix D includes the drawings 237236-000-DRG-LA-001 to 237236-000-DRG-LA-004, showing the seawall resulting from this detailed design. The alignment envisaged is summarised below:

Parallel to shore build the seawall 10m in front of the properties, with the exception of the seawall alignment along number 48 and 50 to be kept as per numbers 52, 54, 58.

The toe of the wall cuts into the existing Kingfisher Esplanade near numbers 60, 70, 72, 74, 76 and 78 the encroachment into the Marine Park is 5m deep

Toe buried at -1m AHD with two oversized scour protection stones at the base of the wall to control seawall toe movement. The Beelbi Creek tidal flat is located at 0.0m AHD. Under extreme scouring, this toe could reach the Lowest Astronomical Tide level while mitigating complete slope failure. This follows EHP guideline requirements for “Building and engineering standards for tidal works”.

Seawall ends to include a smooth transition to allow for “end effects”, with the seawall will be buried in the dune. A 5m return wall is proposed at each end of the seawall

The Beach Protection Authority indicated a 40m short term erosion, due to cyclone storm erosion and it is noted that the alignment does not cover numbers 82, 84 and 86, which are located at less than 40m from the erosions scarp. These properties are closer to the erosion scarp than numbers 48, 50, 52 and 54.

Drawing 237236-000-DRG-LA-002 in Appendix D show the seawall alignment.

3.4 Cross section The cross section toe is to be buried at -1m AHD and includes large rocks at the toe, to mitigate the effect of beach scour during extreme storms. The seawall toe will require monitoring and additional stones may be required to maintain the seawall if and when scour develops.

Armour sizing Following the Van Der Meer and Hudson armour rock wave stability formula and the theoretical depth-limited significant wave height, the median mass of the primary armour for a rock revetment is a 3t rocks for a 50 year ARI storm event. The physical testing provided scaled measurements of waves at the toe of the seawall, and it appeared that the nearshore wave significant height are smaller than the theory suggest, however the maximum waves are combined with surges (due to the combined influence of storm beat and wave set-up) which increases overtopping. Results of the physical testing indicate that 1t armour rock is stable.

However to take into account the effect of stone dilapidation as well as the limitations of the physical testing a rock revetment of 1.5t has been selected. This is a 50% oversize. These boulders are slightly below 0.5m3 volume. The primary armour is to be placed on-top of two layers over two layers of secondary armour of median mass 150kg.

Toe scour In order to lock the toe and to mitigate the effect of scour, the toe of the seawall is to be covered with two larger rocks, selected from the 1.5t stockpile. Nominally, these rocks would be 2t median mass. Theses rocks are likely to settle in lower position, down the seawall slope as scour progresses. This settlement should be progressive and is not to be mistaken for damage as this movement ultimately stabilises the structure foundation.


Capping stones The crest of the seawall has been selected to be at +3.6m AHD.

Adopting such a crest elevation translates into very large overtopping during storms. Overtopping flow was measured to be respectively 111l/m/s, 258l/m/s and 387l/m/s for three seawalls adopting this crest elevation. The measured overtopping is similar to the 200l/m/s standard guideline proposed in section 3.2 of the preliminary design report. We note that this standard was selected for structural stability reason and not to mitigate the effect of flooding.

Physical testing observations demonstrate that it will not be possible to improve and to reduce overtopping hazards with a moderate increase in crest level. The overtopping rate is substantial because most of the overtopping is occurring intermittently under the influence of surges which raise briefly the nearshore water level above the seawall crest. A competent flood mitigation structure would have to be several metres above the level of the esplanade to control this surge and the breaking waves. A working hypothesis to mitigate flooding would be the construction of a coastal levee with a crest elevation at (at least) 6m AHD. This level is 3m higher than the existing land level along the seawall alignment. Such a levee would affect substantially visual amenities, nearshore aesthetics and would be substantially more expensive. Clearly, a coastal levee is beyond a standard seawall solution.

However, the level adopted for the seawall is sufficient to reduce overtopping during moderate storms (king tides).

Oversized rocks have been placed at the crest to protect scour damage to the seawall and these should be placed in Aurecon’s selected pattern placement as indicated on the drawing. The physical testing demonstrated that the pattern placement is resistant to overtopping flow.

The pattern placement is such that the capping rocks are placed in two horizontal layers. Each stone is carefully orientated with its principal dimension (longest length) perpendicular to the seawall alignment. The top capping stone is to be interlocked in between four lower capping stones. Specific instructions to the contractor are required to build this seawall to specification.

The physical testing demonstrates that the stability of the seawall is critically influenced by the quality of the construction of the crest as well as the rock mass. The selected median rock mass at the crest is 4t. The 4t median mass is oversized by 33% from the physical testing 3t cap to account for dilapidation.

Crest scour We note that the dune is likely to scour and the back crest has been simplified to avoid dislodgement of secondary armour behind the crest. The lack of secondary armour directly behind the capping rocks may results in local cave-ins and these areas may require sand back fill from time to time. This reduces the risk of having secondary armour being dislodged and carried by the flow in the beachfront properties following a storm. Should maintenance become excessive, a concrete pavement could be added to reinforce the crest.

Again, the physical extent of cave-ins will depend primarily on the stone selected by the contractor to build the back-row of lower capping stones. If these stone are well interlocked cave ins would not occur unless overtopping becomes significant.

Drawing 237236-000-DRG-LA-003 in Appendix C shows the seawall cross section.


Stair case A 1.2m wide timber staircase is proposed in between properties 66 and 70. This staircase spans over the seawall and will use non slip surfaces to mitigate fall hazards as well as following the requirements of the BCA and relevant design standards. The stairs has not been designed to resist the design storm. This structure may require partial or total re-construction after a significant storm event.

Drawing 237236-000-DRG-LA-004 in Appendix C shows the staircase general arrangement.

3.5 Safe Design A Safe Design register of hazard risk and control measures is presented in Appendix E. This document is a work in progress, which will be completed in coordination with Council and the Contractor selected, following the Tender Phase. This information is subject to future revisions as the project progress.


4. Quantities and cost estimates

4.1 Quantity estimates Table 4 quantity estimate is proposed:

Table 4 Bill of quantities

Material Unit Quantity

Excavations and backfills m3 17,500

Geotextile m2 4,700

Secondary armour, 300kg t 3,500

Rock armour, 1.5t t 7,800

Capping stones, 4t t 3,900

4.2 Cost estimates

4.2.1 Assumed rates Table 5 indicates the units rates adopted for the materials in Table 4.

Table 5 Assumed rates

Material type Unit Adopted rates (excl. GST)

Excavation/backfill m3 $7

Geotextile m2 $25

Secondary armour t $40

Primary armour, 1.5t t $50

Capping stones, 4t t $75

These adopted rates are supply/install rates, exclusive of GST.

These rates consider that the competent excavated beach material (clean sand) will be re-used in a post-construction beach nourishment.

Also it is considered that the loading and unloading of capping stones can be undertaken by excavator grabs, while the primary armour and secondary armour are loaded and installed with an excavator bucket.

Minimum double handling can be achieved by synchronising quarry supply and installation works.


4.2.2 Project costs, risks, and contingencies Table 6 indicates the range and adopted value for the project costs, risks and contingencies.

Table 6 Proposed contingencies

Contingency and fees Typical range Adopted value (Excl. GST)

Contractor overheads [10%-30%], 15%

Contractor mobilisation and demobilisation [$30,000-$150,000] $100,000

Quarry risk (applicable to primary armour material only)

[0-100%] 15%

Weather and program risk [0-100%] 5%

Geotechnical risk (Acid Sulphate Soil, loose material)

[0-30%] 5%

Preliminaries (design, approvals, testing) N/A $130,000

Construction management N/A $40,000

Furniture / railing [$2,000-$10,000] $5,000

Tree clearing [$30,000-$60,000] $50,000

Re-vegetation [$20,000-$100,000] $50,000

Fees and surveys N/A $50,000

4.2.3 Detailed cost breakdown The estimated project capital cost breakdown for the Kingfisher Parade Seawall is detailed in Table 7.

Table 7 Project cost breakdown

Item No. Material Schedule Unit Quantity Rates Total (excl. GST)

Construction

1.1 Excavation/backfill m3 17,500 7 $122,500

1.4 Secondary armour, 150kg t 3,500 40 $140,000

1.2 Rock armour, 1.5t t 7,800 50 $390,000

1.3 Rock armour, 4t t 3,900 75 $292,500

1.5 Timber staircase 1 $20,000

1.6 Geotextile - 600R m2 4,700 25 $117,500

Preliminaries

2.1 Surveys and fees $50,000

2.2 Design, testing and development approval $130,000

2.3 Superintendent / construction management $40,000

2.4 Site preparation $50,000


Item No. Material Schedule Unit Quantity Rates Total (excl. GST)

2.5 Re-vegetation $50,000

2.6 Furniture / railing $5,000

Contractor costs

3.1 Contractor Overheads 15% $162,375

3.2 Contractor mobilisation and demobilisation $100,000

Risks

4.1 Quarry risk 15% $123,375

4.2 Geotechnical risk 5% $54,125

4.3 Weather and program risk 5% $54,125

The total capital cost estimate is $1,880,500, inclusive of stairs, seawall ends, etc... This detailed estimate covers the range contingencies and risk outlined in Table 6.

A firm quote for construction of the seawall has not been obtained from any contractor.

The sum of Items 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2.4, 2.5, 2.6, 3.1, 3.2 indicates that typically the “construction costs” would be approximately $1,500,000 (ex. GST) inclusive of contractor costs, but excluding risks. Actual quotations for construction are likely to vary from contractors to contractors, and the accuracy level of our costing is expected to be up to ± 30%.

The “total risk” accounted in the capital cost estimate is 20%, although typically, only a portion of this is likely to occur during the project.

Project management, tendering and on-going construction management mitigates the risk of unwarranted cost escalations during construction.


5. Conclusion This design report proposes an optimised design for an erosion protection seawall at Kingfisher Parade. This seawall does not provide substantial protection from coastal flooding and overtopping during the design storm is very substantial.

The capital cost estimate of the seawall is approximately $1.9 million (ex GST). Ultimately, the actual capital cost of the seawall will only be known when the structure is built.

Please note that any opinion or estimate of costs by the Principal Consultant will be made on the basis of the Principal Consultant’s experience and qualifications and will represent the Principal Consultant’s judgment as an experienced and qualified Consultant, familiar with seawall and breakwater works. However, the Principal Consultant has no control over the costs of labour, materials, equipment or services furnished by others or either Contractor’s methods of determining prices or over competitive bidding or market conditions. Therefore the Principal Consultant cannot and does not guarantee that proposals, bids or actual construction costs will not vary from the Principal Consultant’s estimates.

Project management and on-going construction management are recommended to reduce the risk of cost escalation during the construction. The contract should be structured to check costs and assigned risks to manage the delivery of the project to cost agreed with the successful contractor for the works.

A Safe Design assessment is underway to finalise this design, however the effect on cost estimate is unlikely to be significant.

Regular monitoring is recommended, particularly at the seawall ends, since erosion is likely to persist. The seawall may need further extensions overtime. Also, the seawall, as any structure, requires on-going maintenance. The crest should be monitored for cave-ins and/or scour, and the toe for settlement following storms. Stone dilapidation survey may occur 5 years after construction, to program any additional maintenance works, if required.

The stairway has not been designed to resist the design storm and will require on-going maintenance to remain safe, sound and functional (stringer brace tightening, painting, etc).

Appendix APreliminary Design Report

Kingfisher Parade Seawall Preliminary Design Report

Reference: 237236

Prepared for: FraserCoast Regional Council

Revision: 2

24 July 2013

Project 237236 File 237236-RP-001-02-Kingfisher Parade Seawall-Preliminary Design Report.docx 24 July 2013Revision 2

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Document control

Report title Preliminary Design Report

Document ID Project number 237236

File path http://localhost:3579/UCdoc~cs/85397074/237236-RP-001-02-Kingfisher Parade Seawall-Preliminary Design Report.docx

Client Fraser Coast Regional Council

Client contact

Rev Date Revision details/status Prepared by Author Verifier Approver

0 22 July 2013 Draft issue for client comment S Dorr JF AC G Colleter

1 23 July 2013 For stakeholder discussion S Dorr J Farnes A Charteris G Colleter

2 24 July 2013 For stakeholder discussion S Dorr J Farnes A Charteris G Colleter

Current revision 2

Approval

Author signature Approver signature

Name Allan Charteris Name Gildas Colleter

Title Associate Title Technical Director

Project 237236 File 237236-RP-001-02-Kingfisher Parade Seawall-Preliminary Design Report.docx 24 July 2013Revision 2 Page 1

Contents1. Project description 3

2. Review of existing data 3

2.1 Key physical features 5

2.2 Gap analysis 7

3. Option analysis 8

3.1 Impact 8

3.2 Effectiveness 8

3.3 Social value/community expectations 9

3.4 Government processes 9

3.5 Economics 10

3.6 Option analysis 10

4. Planning and environmental assessment 13

4.1 Environmental searches 13

4.2 Planning and legislative assessment 14

4.3 Construction management and rehabilitation 16

5. Seawall preliminary design 16

5.1 Design criteria 16

5.2 Standard 16

5.3 Alignment 17

5.4 Cross section 17

6. Quantities and cost estimates 18

6.1 Quantity estimates 18

6.2 Cost estimates 18

7. Recommendations 20


AppendicesAppendix A

References

Appendix B

Examples of erosion control coastal structures

Appendix C

Environmental searches

Appendix D

Drawings

FiguresFigure 1 Proposed seawall alignment 4Figure 2 Seawall cross section – for discussion 5Figure 3 Rock seawall 11Figure 4 Coastal pavement 11

Tables Table 1 Burrum Head Tidal Planes 5Table 2 Toogoom storm tide (m, AHD) – Including wave set-up 6Table 3 Wind Data 6Table 4 Multi-Criteria Analysis 12Table 5 Legislative approval requirements 14Table 6 Bill of quantities 18Table 7 Assumed rates 18Table 8 Proposed contingencies 19Table 9 Project cost breakdown (exc. stairs) 19


1. Project description Over the last decades, the combined action of storm waves and tides are eroding the Toogoom shoreline, particularly along Kingfisher Parade.

The dune buffer along properties 58 to 78 has been reduced to a few metres since the Australia Day 2013 storm (a tropical depression, originating from TC Oswald) and an emergency sand push was undertaken to buffer erosion.

The Fraser Coast Regional Council (FCRC) policy for seawall to protect private properties is that capital costs will be recovered from the residents through a special levy and the seawall asset will be transferred to council once constructed.

This report documents a proposed preliminary design for a seawall along properties 48 to 80 Kingfisher Parade, locking the position of the shoreline and removing the on-going coastal erosion treat and shoreline recession.

This report focuses on three aspects, first of all providing a rationale for the shore protection works envisaged, an engineering description of the seawall and finally an estimate of capital costs.

2. Review of existing data Aurecon reviewed existing information relevant to the project, listed in Appendix A.

In 2005, Aurecon prepared a geo-container seawall design for the Hervey Bay City Council. The design intent of the 2005 seawall was to provide a 10m offset from property boundaries to offer a “last line of defence” seawall to incur minimum damage for the 50 year Average Recurrence Interval (ARI) cyclone event. A geotextile seawall was proposed on the basis of having low confidence in local quarried rock and reducing capital costs. At the time the structure was to be buried into the dune.

More recently, following the Australia Day Storm, Taylor Westerveld proposed a seawall alignment and cross section. Figure 1 shows seawall alignment.


Figure 1 Proposed seawall alignment

Figure 2 show a typical cross section to support the discussions.


Figure 2 Seawall cross section – for discussion

We note that this seawall cross section was only provided for discussion.

2.1 Key physical features Three key physical parameters affect the seawall project, the tidal range and storm tide. Wave action, wind and coastal currents also affect the structure, but are limited greatly by water level variations on such a beach. The wind is an important parameter as it generates the wave action responsible for sediment transport along the beach. It is worth mentioning as well that the Beelbi Creek tidal flat is tide dominated.

2.1.1 Tide Table 1 contains the tidal planes, extracted from the 2011 Queensland Tide Table for Burrum Heads (Bundaberg Standard Port). This is the closest location to Toogoom.

Table 1 Burrum Head Tidal Planes

Tidal Plane m, Chart Datum m, AHD Highest Astronomical Tide (HAT) 3.81 1.99

Mean High Water Spring (MHWS) 3.03 1.21

Mean High Water Neap (MHWN) 2.38 0.56

Australian Height Datum (AHD) 1.82 0

Mean Sea Level (MSL) 1.78 -0.04

Mean Low Water Neap (MLWN) 1.14 -0.68

Mean Low Water Spring (MLWS) 0.49 -1.33

Lowest Astronomical Tide (LAT) 0 -1.82


2.1.2 Storm tide levels Storm surge is an increase water elevation due to the influence of wind shear (wind set-up) and decreased atmospheric pressure associated with low weather systems such as tropical depressions and cyclones. Storm tide is the combination of tide and storm surge and indicates the maximum water level offshore of the surf-zone (the nearshore area, where waves are breaking) during a storm event. The extreme shoreline water level includes both storm tide and wave set-up due to breaking waves.

A comprehensive Monte Carlo storm tide model study was undertaken in 2004 by James Cook University for the Hervey Bay region. This localised study proposed storm tide levels for extreme cyclonic events.

Table 2 indicates the extreme shoreline water levels, inclusive of wave set-up, in the vicinity of Toogoom Beach for various extreme events Average Recurrence Intervals (ARI).

Table 2 Toogoom storm tide (m, AHD) – Including wave set-up

Averaged Recurrence Interval

50 year 100 year 500 year 1,000 year

Annual Exceedance Probability

2% 1% 0.2% 0.1%

Probability of Encounter over 20 years

33% 18% 4% 2%

2004 storm tide level 2.55 2.88 3.58 3.88

2100 storm tide level* 3.15 3.59 4.52 4.89

(*) based on the 2004 study Greenhouse scenario

2.1.3 Wind Table 3 lists the Australian Bureau of Meteorology (BOM) wind stations, within an approximate 100km radius of Toogoom.

Table 3 Wind Data

Station Name Month/Year site opened.

(MM/YYYY)

Latitude to 4 decimal places

Longitude to 4 decimal places

Height of station above mean sea level in metres.

Hervey Bay Wildlife Park Jan-87 -25.2903 152.8153 17

Hervey Bay Airport Mar-99 -25.3203 152.8842 14.5

Maryborough 01/1870 -25.5181 152.7111 11

Bundaberg Aero Jan-42 -24.8885 152.3235 27

Lady Elliot Island Jan-39 -24.1119 152.7158 3.6

Sandy Cape Lighthouse 01/1871 -24.7297 153.2083 99.1

It was found that the dominant wind directions are similar for all stations; and that the wind speeds are also well correlated during storms. For instance, there is a difference of less than 2m/s about 80% of the time between the wind at Sandy Cape and Hervey Bay. This wind information can be used to calculate waves growth towards Toogoom Beach.


2.1.4 Waves The 2004 study included a wave model to estimate ambient waves at Toogoom for the purpose of sediment transport modelling and to inform the design.

The ambient wave heights, for a point located at –5.0m LAT were found to be of small size. Significant wave heights larger than 1.0m are rare, occurring only less than 1% of the time. This finding is similar to 10 years of wave data measurements at Point Vernon by the Beach Protection Authority (1986).

Extreme waves during a storm or a cyclone break over the wide and shallow Beelbi Creek Estuary. The design wave becomes “depth-limited” by this breaking process, which means that the wave heights are constrained by the nearshore shallow water.

2.1.5 Sediment transport and beach alignment The 2004 beach nourishment report models longshore sediment transport. Over the period 1977-2004 it was found that the net sediment transport is going West at a rate of 8,000m3/year under the influence of small waves. Only 30% of this transport occurs on the upper beach (70% of the transport occurs on the Beelbi Estuary flood shoal). During storms, the sediment transport is (briefly) reversed, and directed towards the east.

Shoreline stability The 2004 report indicated that the Kingfisher Parade upper beach dune width was narrowing by an average rate of 1m to 2m per year, while the dune width has increased by about 1m per year close to the Beelbi estuary, creating a sand-lobe. These shoreline changes have continued over 2004-2013, leading to the current erosion issue. This is well demonstrated by superposing of the shoreline survey of 2004 and 2013.

Cyclone erosion BPA evaluated the erosive action of a cyclone to be approximately 40m from the Beelbi Creek Estuary to Toogoom East. A 10m erosive episode, associated with a tropical cyclone, was recorded in February 1863.

2.2 Gap analysis Following the review, no significant gap appears in the description of the physical environment.

However, the ecological value of the foreshore requires investigation. An ecological survey is necessary to inform the detailed design and the preparation of development applications (refer to section 4).


3. Option analysis A Multi Criteria Analysis has been undertaken to compare a range of options plausible to mitigate the erosion problem at Toogoom. Appendix B shows several examples of erosion control coastal structures, which may be considered.

Multi Criteria Analysis is a tool that can be used for complex problems where multiple criteria need to be assessed in the process of making decisions about proposals for future action. Multi Criteria Assessments (MCAs) attempt to incorporate all criteria simultaneously within the analysis, to arrive at a single conclusion or ranking. As such, they can consider a range of complex issues, impacts and opportunities and can therefore be applied to more complex situations than a Cost Benefit Analysis. For these reasons, an MCA process was utilised to inform the selection of a preferred erosion response option.

Five themes are proposed: impact, effectiveness, social Value, government process, economics. The following sections outline factors taken into consideration for each theme.

3.1 Impact The impact or influence of a proposed option is a key consideration, and generally relates to the degree to which an option may change conditions from the status quo (perceived or otherwise defined). Impacts can occur to the environment and to the community.

Marine biodiversity – the degree to which the option may impact marine biodiversity at Toogoom, considering the benthic and pelagic species associated with the beach, intertidal flats and the sub-tidal areas

Beach/dune biodiversity – the degree to which the option may impact beach and dune biodiversity (those areas typically above high tide mark), considering suitability to promote dune vegetation (re-vegetation) and the opportunity for re-colonisation by dune animal species

Environmental impacts beyond Kingfisher Parade – considering the impact of the option on areas farther afield, including the impact on materials source areas, and up/down coast impacts due to changes in sand supply or generation of plumes etc.

Navigation – the impact the option may have on safe navigation within Beelbi Creek and/or ability to safely beach boats and other recreational vessels

Construction impact – in relative terms, the area directly affected by the proposed option, both in terms of option footprint as well as construction impacts for the materials sourcing areas. This criteria may also capture issues relating to the degree to which construction works may interfere with beach use

Construction timing – the time taken to undertake construction, and also considers the flexibility of timing (ie the degree to which external influences may restrict the timing of works)

Non-beach users – the degree to which the option may impact on non-beach users within the community. For example, nourishment options that use quarried sand may impact non-beach users by way of increased truck traffic on local roads

3.2 Effectiveness The effectiveness of the option to address the erosion problem is assessed via a range of criteria. Consideration is given to both the upside (addressing the problem) and downside risk (failure consequence) of each option as well as assessment of option specific uncertainties.

Longevity of design – consideration of design life under typical conditions


Addresses incident wave problem – degree to which solution directly attenuates incident waves, creating a reduced wave energy condition at the beach

Addresses sand budget imbalance – degree to which solution ameliorates the recognized imbalance between longshore supply from the east and storm sediment transport from the west

Addresses shoreline recession – degree to which solution reduces or eliminates beach recession Failure consequence – considers the downside risk of failure of the proposed option, perhaps due to exposure to conditions beyond design criteria, where consequences could include potential loss of life or damage to public/private property and/or infrastructure

Technology challenges – provides a measure of the uncertainty associated with proven vs. new technology, and considers options proven/suitable for conditions at Kingfisher Parade through to new technology unproven in the Hervey Bay or elsewhere

Integration/compatibility with existing – considers how difficult it may be to integrate the proposed option with the existing infrastructure

Adapts to short term cyclic variations – degree to which the option can accommodate short term (seasonal, storm) cycles in sand supply, wave climate, water levels

Adapts to long term changes – degree to which the option can accommodate long term (annual, climate change, ENSO) cycles in sand supply, wave climate, water levels

3.3 Social value/community expectations The local and extended community of beach users have expectations about Toogoom Beach. Recent storm wave conditions, erosion and the subsequent sand-pushes are inconsistent with these expectations (whether real or perceived). An important measure of the appropriateness of the proposed solution option is the degree to which the values held by the community can be preserved.

Visual amenity – the degree to which the option meets with the community’s expectation of what Toogoom Beach should look like, and/or the degree to which an option may detract from such expectations about the beach

Beach safety – considers issues such as: does the option provide safe access to the beach, create a safe beach user area, promote safe swimming, or provide opportunity for the safe use of recreational water craft

Sense of place – degree to which the option may alter the sense of place, or community connectedness to Toogoom Beach

Suitability of Materials – degree to which the community may accept proposed materials, recognizing the materials’ adaptability for use (or not) for stairs, walkways, informal seating and an assessment of other material specific issues including user-friendliness, colonization of pests, litter, maintenance and odour

3.4 Government processes This theme considers the Governmental process challenges associated with each option.

Roles and responsibilities – degree to which various local, state and federal government roles and responsibilities are clearly defined, and one end of the scale requiring significant effort to resolve (perhaps outside the existing policy scope) to being clearly set out within existing arrangements

Compliance with Coastal Protection and Management Act and Marine Park Act – as a guiding principal, the CPMA and MPA is a crucial reference for proposed actions at Toogoom Beach. This measure captures the degree to which the option is consistent with the CPMA and MPA policies and objectives


Approvals process – considers the requirements of approving the proposed option, whether secured via existing well understood pathways or requiring significant additional levels of approval not typical of “business as usual”

3.5 Economics Cost is a major factor in any infrastructure project. Further, it is recognized that the Kingfisher Parade shore protection work is subsidised by the residents located along the beach. One completed, the shore protection work will become part of the Fraser Coast Regional Council portfolio of coastal assets and accordingly, capital cost is not the only consideration.

Capital Cost – in relative dollar terms the up-front cost of the option, including materials costs, site construction activities, and any environmental (or other) monitoring linked to the option

Maintenance Cost – the cost of periodic routine maintenance Lifecycle cost – The total cost of the asset each year, over its design life Intergenerational Equity – assesses the clean-up cost and/or other burdens on future generations, once the option has finished its design life

3.6 Option analysis Table 4 summarises the findings of a MCA, prepared as a desktop level. It is important to consider that this is not a final assessment and is subject to feedback from relevant stakeholders.

While recognising that all the above themes and factors are relevant, it is important to consider than options are limited by governmental processes. Therefore, when possible, “red cards” have been drawn on options that are unlikely to be acceptable to Governmental Agencies. This mostly leaves the various seawall options as being the practical avenues for the project.

In the impact column we have simply noted the typical intervention cycle required to maintain the structure, which measures impact on residents. It shows that the geotextile seawall would require more intervention year on year than most other seawall types.

A concrete seawall as typically expensive to build and difficult to repair, although unreinforced coastal pavements can be deployed on a beach face, we note that these do typically higher installation costs. Stone masonry seawalls are very expensive in Australia, as building such structures is very labour intensive.

A Figure 3 rock amour seawall is optimum, provided that sufficient armour stone can be procured economically. It is recommended to investigate Dondowran Quarry to confirm what armour stones can be won locally and economically.

If armour stones are difficult to procure, Figure 4 shows a typical coastal pavement, which could be envisaged as an alternative, although such a revetment is likely to be more expensive to install and to maintain.


Figure 3 Rock seawall

Figure 4 Coastal pavement

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4. Planning and environmental assessment The following section outlines the planning and environmental framework applicable to the proposed development, including the identification of potential environmental constraints and development permits that are likely to be required for the works.

Note this information is provided based on a preliminary review of the proposed works only and will be subject to refinement throughout the duration of the project.

4.1 Environmental searches To identify any environmental constraints or features applicable to the project area, searches have been undertaken of the following databases:

Department of Environment and Heritage Protection (DEHP) Regional Ecosystem (RE) Mapping

DEHP Queensland Coastal Plan Mapping

Department of National Parks, Recreation, Sport and Racing (DNPRSaR) Fish Habitat Area Maps

DNPRSaR Protected Areas Mapping

Department of Sustainability, Water, Population and Communities (SEWPaC) Environmental Protection and Biodiversity Conservation Act 1999 (EPBC Act) Protected Matters Online Search Tool

Queensland Government Wildlife Online Database

DEHP Queensland Heritage Register

Department of Aboriginal and Torres Strait Islander and Multicultural Affairs (DATSIMA) Aboriginal Cultural Heritage Database

Relevant search results and mapping is included within Appendix C.

4.1.1 Results Search results identify that tidal waters seaward of the site are designated within the Beelbi Fish Habitat Area (FHA) (administered by DAFF), and the Great Sandy Marine Park (administered by the DNPRSaR). In addition, the subject site contains vegetation identified as a ‘Least Concern Regional Ecosystem’ protected under the Vegetation Management Act 1999.

Results of the EPBC Protected Matters Search identify one threatened ecological community (Lowland Rainforest of Subtropical Australia), 41 threatened species and 51 listed migratory species as potentially occurring within a 5 km radius of the site. The 41 listed threatened species are made up of 11 species of birds, one frog, eight mammals, 10 plants, eight reptiles and three shark species.

There are no significant heritage features identified within the vicinity of the site. However, it is noted that at the time of writing the results of an Aboriginal Cultural Heritage database search remain outstanding.

These results of these searches influence the planning requirements for the project in terms of both legislative approvals, as well as the criteria which must be addressed within subsequent development applications. Accordingly, an indication of the potential approval requirements for the project based on these results is provided below.


4.2 Planning and legislative assessment A number of development permits may be potentially required to authorise construction of the seawall. It is noted that the need for some approval requirements will be dependent on the location of works in relation to tidal boundaries, as well as the type and extent of any vegetation clearing.

Table 5 below provides a summary of the potential legislative approval requirements for the works and the relevant development triggers.

Table 5 Legislative approval requirements

Permit/Approval Legislation Administering authority

Trigger Statutory timeframes

Operational Works that are Prescribed Tidal Works

Coastal Protection and Management Act 1995

DEHP Undertaking tidal works IDAS timeframes apply*.

Referral of proposed action

Environmental Protection and Biodiversity Conservation Act 1999

SEWPaC Impacts to federally listed species or habitat.

20 business days.

Operational Works within a Declared Fish Habitat Area (FHA)

Fisheries Act 1994 DAFF Undertaking assessable works completely or partly within the boundaries of the Beelbi Fish Habitat Area

IDAS timeframes apply*.

Operational Works for the removal, destruction or damage to marine plants

Fisheries Act 1994 DAFF Clearing of marine plant species


Marine Park Permit Marine Parks Act 2004

DNPRSaR Undertaking works within the boundaries of the Great Sandy Strait Marine Park

No statutory timeframesapplicable.

Applications typically take up to three months,which includes a 35 business day period for Native Title Notification.

Operational Works for vegetation clearing

Vegetation Management Act 1999

DNRM Clearing of remnant vegetation on unallocated state land.


Operational Works for Vegetation Clearing under a Planning Scheme

Sustainable Planning Act 2009

FCRC Undertaking the clearing of vegetation identified as assessabledevelopment under the Hervey Bay Planning Scheme.


Operational Works for Filling and Excavation under a Planning Scheme

Sustainable Planning Act 2009

FCRC Undertaking filling or excavation in excess of 100m3



Permit/Approval Legislation Administering authority

Trigger Statutory timeframes

Protected Plants Clearing Permit under

Nature Conservation Act 1992

DNPRSaR Destruction or damage to native flora/fauna.

40 business days (with an additional 20 business day informationrequest period).

*IDAS assessment timeframes are specified within SPA, and are dependent on the number of referral agencies and whether any information requests are issued by regulatory authorities. Typically, applications for Code Assessable development take between three to six months to obtain.

4.2.1 Comments The development of the seawall will require a development application for Operational Works that are Prescribed Tidal Works under the Sustainable Planning Act 2009 and the Coastal Protection and Management Act 1995. As the works are located within a local government tidal area, the Fraser Coast Regional Council (FCRC) will act as the Assessment Manager for this development application, with DEHP acting as a concurrence agency with jurisdiction to assess coastal management aspects of the project.

The need for additional development permits listed in Table 5 will be dependent on the extent of works in relation to various jurisdictional boundaries, and the need for any vegetation clearing to enable construction of the seawall. In particular, according to advice received from DAFF and the DNPRSaR, where works are located seaward of the ‘esplanade’ which runs alongside the coastline, the works will be located within the boundaries of the Beelbi FHA and the Great Sandy Marine Park. In this instance the project may trigger additional approval requirements such as a Marine Park Permit and Operational Works within a Fish Habitat Area.

It is also noted that consideration to construction access and laydown requirements will also be required in order to properly determine the approval requirements. For example, a Marine Park Permit will be required where construction access or the laydown of material is required seaward of the ‘esplanade’ and within the boundaries of the Great Sandy Marine Park.

4.2.2 Vegetation clearing It is highlighted that where vegetation is to be removed, clearing activities may trigger a number of legislative approvals depending on the type of species present and their level of protection under State and Federal legislation. Consideration to the potential impacts on fauna species and their habitat will also be required.

For example, the clearing of marine plant species (such as Salt Couch) will require an application for the removal, destruction or damage to marine plants under the Fisheries Act 1994. Additionally, vegetation alongside the coastal reserve (or ‘esplanade’) is identified as ‘Remnant vegetation comprising least concern regional ecosystems’ protected under the VM Act. As this vegetation is located on State land, there are no applicable clearing exemptions which may be utilised for the works, and development permit will be required under the VM Act where the clearing of this vegetation is proposed.

Other permitting requirements may be triggered for impacts to native flora or fauna under the Nature Conservation Act 1992, or the EPBC Act for species protected at Federal level.

An ecological survey will be required in order to accurately determine the development approvals required to authorise vegetation clearing. The survey will need to consider all aspects of the project


including any additional clearing which may be required during construction activities (eg. access and laydown areas).

4.3 Construction management and rehabilitation While the project is currently in the preliminary design stages, consideration to construction requirements and measures to ensure environmental protection should be considered early to avoid potential project delays.

A Construction Environmental Management Plan (CEMP) will be required to be developed for the project to identify arrangements for construction activities, including consideration to the sources and transport of rock material; availability and location of laydown areas; and measures to ensure protection of the environment and public health and safety during this period. As the works will be located on land below 5 m AHD, control measures for the management of potential Acid Sulfate Soil must also be established.

In addition, where vegetation clearing is required, advice received from the DNRM has indicated that a re-vegetation strategy will be required to demonstrate measures to re-instate RE’s which are removed as a result of the works. This matter should also be considered early in the approvals process in order to minimise delays to the commencement of construction.

Couch grass along the properties boundaries and mulch over the remaining of the project footprint (above HAT) have been discussed with Council as possible re-vegetation means.

5. Seawall preliminary design

5.1 Design criteria

5.1.1 Design water level The design water level combined the 50 year storm tide level of 2.55m AHD with a Sea Level Rise allowance of + 0.30 m for year 2063, covering a “standard” 50 year design life for the structure. This is a design water level of +2.85m AHD.

5.1.2 Design waves Depth limitation wave calculation indicates a 50 year ARI significant wave height of 2.5m. This was used as a design wave condition. The 2004 seawall design substantiated a wave peak period of 8 to 10 second, based on wave modelling.

5.2 Standard The minimum development standard for a seawall is 50 year design standard for a design life of 50 years. This follows the Department of Environment and Heritage minimum requirements for seawalls.

There is no specific provision for overtopping rate for seawalls as these structures are not designed to mitigate both erosion and flooding.

A coastal levee could be designed to mitigate the effect of coastal flooding. Typically, the averaged overtopping rate on top of such a levee should be below 200l/s/m. This is typically the rate a


reinforced levee can sustain with minimum damage. Building such a levee would mean a final crest level much higher than the land level along the beach properties.

5.3 Alignment Appendix D includes the drawings 237236-000-DRG-LA-001 to 237236-000-DRG-LA-005, showing the seawall resulting from this preliminary design assessment. The alignment envisaged is summarised below:

Parallel to shore build the seawall 10m in front of the properties, with the exception of the seawall alignment along number 48 and 50 to be kept as per numbers 52, 54, 58.

Toe buried at -1m AHD with two oversized scour protection stones at the base of the wall to control seawall toe movement. The Beelbi Creek tidal flat is located at 0.0m AHD. Under extreme scouring, this toe could reach the Lowest Astronomical Tide level while mitigating complete slope failure. This follows EHP guideline requirements for “Building and engineering standards for tidal works”;

Seawall ends to include a smooth transition to allow for “end effects”, with the seawall will be buried in the dune. A 5m return wall is proposed at each end of the seawall.

Drawing 237236-000-DRG-LA-003 and Drawing 237236-000-DRG-LA-004 in Appendix C show two possible seawall alignments nominated as Option A and Option B.

For Option A, the toe of the wall cuts into the existing Kingfisher Esplanade near numbers 60, 70, 72, 74, 76 and 78 the encroachment into the Marine Park is 7m deep. This seawall is not considered to be compatible with the current legislation as this encroachment is very deep.

For Option B, the toe of the wall cuts into the existing Kingfisher Esplanade near numbers 60, 70, 72, 74 and 76, however the encroachment into the Marine Park is less than 1m. This alignment reduces the buffer to properties 74 and 76 down to 5m. This seawall arrangement will be considered for quantity estimation and costing.

It is also noted that the alignment does not cover numbers 82, 84 and 86, which are located at less than 40m from the erosions scarp, and closer to the erosion scarp than numbers 48, 50, 52 and 54. The Beach Protection Authority indicated a 40m short term erosion, due to cyclone storm erosion.

5.4 Cross section The cross section toe is to be buried at -1m AHD and include large rocks at the toe, to mitigate the effect of beach scour during extreme storms. The seawall toe will require monitoring and additional stones may be required to maintain the seawall if and when scour develops.

Following the Van Der Meer and Hudson armour rock wave stability formula, the median mass of the primary armour for a rock revetment is a 3t rocks for a 50 year ARI storm event. These boulders are slightly over 1m3 of volume. The primary armour is to be placed on-top of two layers over two layers of secondary armour of median mass 300kg.

The crest of the seawall has been selected to be at +3.6m AHD. Adopting such a low crest translates into very large overtopping during storms, likely to be in the order of 1,000l/m/s. Oversized rocks have been placed at the crest to protect scour damage to the seawall. We note that the dune is likely to scour and the crest has been extended to provide some flexibility.

The cross section of the seawall is such that the seawall height would need to be located at +5.2m AHD to reduce the median overtopping rate below 200l/s. This is 2.20m higher than the land level


along the seawall alignment which is approximately +3.0m AHD. Such a levee would affect substantially visual amenities and nearshore aesthetics.

A 5m wide concrete staircase is proposed in between properties 66 and 70, and this staircase has been protected each side by oversized 6t rocks to mitigate movements of primary armour in this region.

Drawing 237236-000-DRG-LA-002 in Appendix C shows the seawall cross section.

6. Quantities and cost estimates

6.1 Quantity estimates Following the production of this preliminary design, the Table 6 is proposed:

Table 6 Bill of quantities

Material Unit Quantity

Excavation/backfill m3 17,500

Rock armour, 3t t 8,900

Rock armour, 6t t 6,200

Secondary armour, 300kg t 5,100

Concrete t 60

Geotextile m2 5,100

6.2 Cost estimates

6.2.1 Assumed rates Table 7 indicates the units rates assumed for the materials in Table 6.

Table 7 Assumed rates

Material type Unit Assumed rates

Excavation/backfill m3 $10

Primary armour (6t or 3t) t $60

Secondary armour t $50

Concrete t $330

Geotextiles m2 $30

These rates are assumed to be supply/install rates but are exclusive of GST and have been based on a supply rate at the Dundowran quarry of $/t 26.73 ex. bin, plus quality control, transport, stockpiling, and placement costs.


6.2.2 Contingencies Table 8 indicates contingencies proposed for the project

Table 8 Proposed contingencies

Contingency and fees Typical range Proposed value

Contractor overheads [+5%, +30%], +15%

Contractor mobilisation and demobilisation [$30,000-$150,000] $100,000

Quarry risk (applicable to quarry material only) [0, +100%] +30%

Weather and program risk [0, +100%] +5%

Geotechnical risk (Acid Sulphate Soil, loose material)

[0, +30%] +5%

Escalation during detailed design (*) [-30% to +30%] +10%

Engineering, procurement, construction management

[+5%, +15%] +10%

Furniture / railing [$2,000, $10,000] $5,000

Tree clearing [$30,000, $60,000] $50,000

Re-vegetation [$20,000, $100,000] $50,000

Fees and surveys N/A $50,000

Detailed design escalation covers features which may become required during the consultation and detailed design process.

A risk assessment will developed at the onset of the detailed design phase, to reduce the range of uncertainties on these contingences.

6.2.3 Cost breakdown The estimated project capital cost breakdown for the Kingfisher Parade Seawall is detailed in Table 9.

Table 9 Project cost breakdown (exc. stairs)

Material Unit Quantity Cost

Excavation/backfill m3 17,500 $175,000

Rock armour, 3t t 8,900 $534,000

Rock armour, 6t t 6,200 $372,000

Secondary armour, 300kg T 5,100 $255,000

Geotextile m2 5,100 $153,000

Fees and contingencies (Table 8)

N/A 1 $1,268,350

Total $2,757,350

The capital cost estimate is approximately $2,750,000. This estimate covers the fees and contingencies, as outlined in Table 8.


The estimated capital cost of the stairs, including furniture (handrail, etc...) and contingencies would be approximately $40,000.

Detailed design, development approval consultations, project management, selection of an appropriate contract for construction, contractor engagement and on-going construction management mitigates the risk of further cost escalation.

7. Recommendations The development applications required for the works have been identified based on a review of environmental features relevant to the subject area and the applicable legislative framework.

It is noted that the development approvals identified are based on a preliminary review of the works. These will be subject to refinement over the course of the project as detailed design is undertaken and construction arrangements are confirmed.

The key actions required to confirm the approval requirements for the project include the following:

Undertake an ecology survey to identify potential impact to protected flora/fauna species and confirm approval requirements under the EPBC Act, Fisheries Act, NC Act, and VM Act;

Confirm the alignment of the seawall in relation to tidal boundaries and ‘esplanade’;

Confirm ‘worst case’ clearing footprint; and

Confirm source of quarry material and arrangements for the materials storage and laydown for the construction period – Dondowran Quarry is to be investigated.

On-going discussion with regulatory agencies will also be required as the design progresses to ensure they remain aware of any progressions or amendments in the design, and to identify any supporting information requirements for the necessary development applications.

Regular monitoring is recommended, particularly of the seawall ends as erosion is likely to persist. The seawall may need further extensions overtime.

Detailed design, development approval consultations, project management, selection of an appropriate contract for construction, contractor engagement and on-going construction management are recommended to detail the cost estimates further and to provide control on future cost changes.

Ultimately, the actual capital cost of the seawall will only be known when the structure has been completed.

Appendix AReferences

Appendix A References

"Australian Port, Environmental Data and Risk Analysis, Phase 1: Literature Review", Australian Geological Survey Organisation (AGSO), 1998

“Building and engineering standards for tidal works”, July 2004, Queensland Government Environmental Protection Agency

“Climate change adaptation Guidelines in coastal management and planning”, The National Committee on Coastal and Ocean Engineering (NOCCE), Engineers Australia, 2012

“Climate modelling report supporting the IPCC’s Fifth Assessment Report”, Queensland Department of Environment and Resource Management, 2012

“Climate risks to Australia’s coast, a first pass national assessment”, Australian Government Department of Climate Change, 2009

“Coastal Engineering Guidelines for working with the Australian Coast in an ecologically sustainable way”, The National Committee on Coastal and Ocean Engineering (NOCCE), Engineers Australia, 2012

“Coastal Engineering Manual _ Part 2, Chapter 1 Water Wave Mechanics”, US Army Corps of Engineer, 2000

“Coastal Engineering Manual _ Part 2, Chapter 2 Meteorology and Wave Climate”, US Army Corps of Engineer, 2000

“Coastal Engineering Manual _ Part 2, Chapter 4 Surf-Zone Hydrodynamics”, US Army Corps of Engineer, 2000

“Coastal Engineering Manual _ Part 3, Chapter 2 Longshore Sediment Transport”, US Army Corps of Engineer, 2000

“Coastal Engineering Manual _ Part 3, Chapter 3 Cross-Shore Sediment Transport Processes”, US Army Corps of Engineer, 2000

“Conservation Technical Report 10 “Storm Tide Threat in Queensland: History, prediction and relative risks”, Bruce Harper, Department of Environment and Heritage, 1999

“Flow in channels”, RHJ Sellin, Macmillan, 1969

“Guideline for responding to the effect of climate change in coastal and ocean engineering”, The National Committee on Coastal and Ocean Engineering (NOCCE), Engineers Australia, 2012

“Guideline for Responding to the Effects of Climate Change in Coastal and Ocean Engineering”, Engineers Australia _ The National Committee on Coastal and Ocean Engineering, 2004 update

“Guideline for the design of maritime structures, AS4997-2005”, Standards Australia

“Hervey Bay Beaches – Present Situation and Recommendations for Beach Protection”, December 1997, Central Queensland University, Dr Jurek Piorewicz

“Hervey Bay Beaches”, June 1989, Beach Protection Authority

“Hervey Bay Foreshore Revetment Walls – A technical Assessment”, December 1999, Coastal Engineering Solution

“Hervey Bay Storm Tide Study – Final Report”, January 2002, Lawson and Treloar

“Hervey Bay, Field Measurements and their Analysis”, January 1999, Central Queensland University, Dr Jurek Piorewicz

“Kingfisher Parade Seawall – Design Report”, Connell Wagner, August 2005

“Predictive Computational Model for Beach and Dune Erosion During Storm Surges,” Proceedings, American Society of Civil Engineers Specialty Conference on Coastal Structures ’83, pp 806-819, Vellinga, P. 1983

“Proposed Seawall at Kingfisher Parade”, Queensland Government Environmental Protection Agency, 12 January 2005

“Queensland climate change and community vulnerability to tropical cyclones”, James Cook University, SEA, Bureau Of Meteorology for Queensland Department of Natural Resources and mines Department of Emergency Services and Environmental Protection Agency, 2004

“Queensland coastal plan – coastal hazards guideline”, Department of Environment and Resource Management, January 2012

“Queensland coastal processes and climate change”, Department of Environment and Resource Management, April 2011

“Sea-level rise as a cause of shore erosion,” Journal of Waterways and Harbour Division, American Society of Civil Engineers, Vol 88, pp117-130, Bruun, P., 1962

“Shore Protection Manual”, US Army Corps of Engineer, 1984

“Structural design actions - Part 2: Wind actions, AS1170.2”, Standards Australia

“Tide Table and boating Safety Guide 2012”, Queensland Government Maritime Safety Queensland, 2012

“Toogoom Seawall – Acid Sulfate Soil Management Plan – Hervey Bay”, Connell Wagner, April 2005

“Variability and trends in the Australian wave climate and consequent coastal vulnerability”, CSIRO, 2008

Appendix BExamples of erosion control

coastal structures

Appendix B Examples of erosion control coastal structures

A 1 geobag seawall

A 2 rock seawall

A 3 grouted rock seawall

A 4 irregular concrete blocks

A 5 regular concrete blocks

A 6 seabees

A 7 concrete seawall vertical

A 8 concrete seawall sloped

A 9 concrete seawall stepped

A 10 masonry seawall vertical

A 11 masonry seawall sloped

A 12 masonry seawall stepped

A 13 managed retreat

B1Replace part of pier withRock groyne

B6 Concrete wave panel

B16Detached submergedbreakwater/reef

B20Detached emergentbreakwater

B24 Refractive sand shoal

B25 Wave breaking sand shoal

B27 Floating breakwater

C1 Headland

C2 Pocket beaches

C-3 pocket beaches - rock T groynes

C-4 pocket beaches - rock tombolos

C-7 nourishment A

C-11 sand recycling

C-12 Sand harvesting

Appendix CEnvironmental searches

EPBC Act Protected Matters Report

This report provides general guidance on matters of national environmental significance and othermatters protected by the EPBC Act in the area you have selected.

Information on the coverage of this report and qualifications on data supporting this report arecontained in the caveat at the end of the report.

Information is available about Environment Assessments and the EPBC Act including significanceguidelines, forms and application process details.

Other Matters Protected by the EPBC Act

Acknowledgements

Buffer: 1.0Km

Matters of NES

Report created: 10/07/13 10:44:07

Coordinates

This map may contain data which are©Commonwealth of Australia(Geoscience Australia), ©PSMA 2010

CaveatExtra Information

DetailsSummary

Summary

This part of the report summarises the matters of national environmental significance that may occurin, or may relate to, the area you nominated. Further information is available in the detail part of thereport, which can be accessed by scrolling or following the links below. If you are proposing toundertake an activity that may have a significant impact on one or more matters of nationalenvironmental significance then you should consider the Administrative Guidelines on Significance.

Matters of National Environmental Significance

Listed Threatened Ecological Communities:

Listed Migratory Species:

None

Great Barrier Reef Marine Park:Wetlands of International Importance:

Listed Threatened Species:

None

34

NoneNone

National Heritage Places:

Commonwealth Marine Areas:

World Heritage Properties:

None

None

50

This part of the report summarises other matters protected under the Act that may relate to the areayou nominated. Approval may be required for a proposed activity that significantly affects theenvironment on Commonwealth land, when the action is outside the Commonwealth land, or theenvironment anywhere when the action is taken on Commonwealth land. Approval may also berequired for the Commonwealth or Commonwealth agencies proposing to take an action that is likelyto have a significant impact on the environment anywhere.

The EPBC Act protects the environment on Commonwealth land, the environment from the actionstaken on Commonwealth land, and the environment from actions taken by Commonwealth agencies.As heritage values of a place are part of the 'environment', these aspects of the EPBC Act protect theCommonwealth Heritage values of a Commonwealth Heritage place and the heritage values of aplace on the Register of the National Estate.

This part of the report summarises other matters protected under the Act that may relate to the areayou nominated. Approval may be required for a proposed activity that significantly affects theenvironment on Commonwealth land, when the action is outside the Commonwealth land, or theenvironment anywhere when the action is taken on Commonwealth land. Approval may also berequired for the Commonwealth or Commonwealth agencies proposing to take an action that is likelyto have a significant impact on the environment anywhere.

A permit may be required for activities in or on a Commonwealth area that may affect a member of alisted threatened species or ecological community, a member of a listed migratory species, whalesand other cetaceans, or a member of a listed marine species.

Other Matters Protected by the EPBC Act

NoneNone12

Listed Marine Species:Whales and Other Cetaceans:

90Commonwealth Heritage Places:

NoneNone

Critical Habitats:

Commonwealth Land:

Commonwealth Reserves:

This part of the report provides information that may also be relevant to the area you have nominated.

Extra Information

Regional Forest Agreements:24

Place on the RNE:4

1Invasive Species:

None

Nationally Important Wetlands:

State and Territory Reserves:1

Key Ecological Features (Marine) None

Details

Listed Threatened Species [ Resource Information ]Name Status Type of PresenceBirds

Australasian Bittern [1001] Endangered Species or specieshabitat may occur withinarea

Botaurus poiciloptilus

Red Goshawk [942] Vulnerable Species or specieshabitat likely to occurwithin area

Erythrotriorchis radiatus

White-bellied Storm-Petrel (Tasman Sea), White-bellied Storm-Petrel (Australasian) [64438]

Vulnerable Species or specieshabitat likely to occurwithin area

Fregetta grallaria grallaria

Squatter Pigeon (southern) [64440] Vulnerable Species or specieshabitat may occur withinarea

Geophaps scripta scripta

Swift Parrot [744] Endangered Species or specieshabitat may occur withinarea

Lathamus discolor

Southern Giant-Petrel [1060] Endangered Species or specieshabitat may occur withinarea

Macronectes giganteus

Northern Giant-Petrel [1061] Vulnerable Species or specieshabitat may occur withinarea

Macronectes halli

Kermadec Petrel (western) [64450] Vulnerable Species or specieshabitat may occur withinarea

Pterodroma neglecta neglecta

Australian Painted Snipe [77037] Endangered Species or specieshabitat may occur withinarea

Rostratula australis

Campbell Albatross [82449] Vulnerable Species or speciesThalassarche melanophris impavida

Matters of National Environmental Significance

Name Status Type of Presencehabitat may occur withinarea

Black-breasted Button-quail [923] Vulnerable Species or specieshabitat likely to occurwithin area

Turnix melanogaster

Mammals

Large-eared Pied Bat, Large Pied Bat [183] Vulnerable Species or specieshabitat may occur withinarea

Chalinolobus dwyeri

Northern Quoll [331] Endangered Species or specieshabitat may occur withinarea

Dasyurus hallucatus

Southern Right Whale [40] Endangered Species or specieshabitat likely to occurwithin area

Eubalaena australis

Humpback Whale [38] Vulnerable Congregation oraggregation known tooccur within area

Megaptera novaeangliae

Koala (combined populations of Queensland, NewSouth Wales and the Australian Capital Territory)[85104]

Vulnerable Species or specieshabitat may occur withinarea

Phascolarctos cinereus (combined populations of Qld, NSW and the ACT)

Grey-headed Flying-fox [186] Vulnerable Foraging, feeding orrelated behaviour knownto occur within area

Pteropus poliocephalus

Other

Pineapple Zamia [5712] Endangered Species or specieshabitat likely to occurwithin area

Macrozamia pauli-guilielmi

Plants

Wedge-leaf Tuckeroo [3205] Vulnerable Species or specieshabitat likely to occurwithin area

Cupaniopsis shirleyana

Lesser Swamp-orchid [5872] Endangered Species or specieshabitat may occur withinarea

Phaius australis

Mt Berryman Phebalium [81869] Critically Endangered Species or specieshabitat may occur withinarea

Phebalium distans

Siah's Backbone, Sia's Backbone, Isaac Wood[21618]

Endangered Species or specieshabitat likely to occurwithin area

Streblus pendulinus

Minute Orchid, Ribbon-root Orchid [10771] Vulnerable Species or specieshabitat may occur withinarea

Taeniophyllum muelleri

Reptiles

Loggerhead Turtle [1763] Endangered Breeding known to occurwithin area

Caretta caretta

Green Turtle [1765] Vulnerable Breeding known to occurwithin area

Chelonia mydas

Collared Delma [1656] Vulnerable Species or specieshabitat may occur withinarea

Delma torquata

Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Breeding likely to occurwithin area

Dermochelys coriacea

Name Status Type of Presence

Hawksbill Turtle [1766] Vulnerable Species or specieshabitat known to occurwithin area

Eretmochelys imbricata

Dunmall's Snake [59254] Vulnerable Species or specieshabitat may occur withinarea

Furina dunmalli

Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Species or specieshabitat known to occurwithin area

Lepidochelys olivacea

Flatback Turtle [59257] Vulnerable Breeding known to occurwithin area

Natator depressus

Sharks

Grey Nurse Shark (east coast population) [68751] Critically Endangered Species or specieshabitat may occur withinarea

Carcharias taurus (east coast population)

Green Sawfish, Dindagubba, Narrowsnout Sawfish[68442]

Vulnerable Species or specieshabitat may occur withinarea

Pristis zijsron

Whale Shark [66680] Vulnerable Species or specieshabitat may occur withinarea

Rhincodon typus

Listed Migratory Species [ Resource Information ]* Species is listed under a different scientific name on the EPBC Act - Threatened Species list.Name Threatened Type of PresenceMigratory Marine Birds

Fork-tailed Swift [678] Species or specieshabitat likely to occurwithin area

Apus pacificus

Southern Giant-Petrel [1060] Endangered Species or specieshabitat may occur withinarea

Macronectes giganteus

Northern Giant-Petrel [1061] Vulnerable Species or specieshabitat may occur withinarea

Macronectes halli

Flesh-footed Shearwater, Fleshy-footedShearwater [1043]

Foraging, feeding orrelated behaviour likelyto occur within area

Puffinus carneipes

Little Tern [813] Species or specieshabitat may occur withinarea

Sterna albifrons

Campbell Albatross [64459] Vulnerable* Species or specieshabitat may occur withinarea

Thalassarche impavida

Migratory Marine Species

Bryde's Whale [35] Species or specieshabitat may occur withinarea

Balaenoptera edeni

Loggerhead Turtle [1763] Endangered Breeding known to occurwithin area

Caretta caretta

Green Turtle [1765] Vulnerable Breeding known to occurwithin area

Chelonia mydas

Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Breeding likely to occurwithin area

Dermochelys coriacea

Name Threatened Type of Presence

Dugong [28] Species or specieshabitat known to occurwithin area

Dugong dugon

Hawksbill Turtle [1766] Vulnerable Species or specieshabitat known to occurwithin area

Eretmochelys imbricata

Southern Right Whale [40] Endangered Species or specieshabitat likely to occurwithin area

Eubalaena australis

Porbeagle, Mackerel Shark [83288] Species or specieshabitat may occur withinarea

Lamna nasus

Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Species or specieshabitat known to occurwithin area

Lepidochelys olivacea

Humpback Whale [38] Vulnerable Congregation oraggregation known tooccur within area

Megaptera novaeangliae

Flatback Turtle [59257] Vulnerable Breeding known to occurwithin area

Natator depressus

Irrawaddy Dolphin [45] Species or specieshabitat likely to occurwithin area

Orcaella brevirostris

Killer Whale, Orca [46] Species or specieshabitat may occur withinarea

Orcinus orca

Whale Shark [66680] Vulnerable Species or specieshabitat may occur withinarea

Rhincodon typus

Indo-Pacific Humpback Dolphin [50] Breeding known to occurwithin area

Sousa chinensis

Migratory Terrestrial Species

White-bellied Sea-Eagle [943] Species or specieshabitat known to occurwithin area

Haliaeetus leucogaster

White-throated Needletail [682] Species or specieshabitat known to occurwithin area

Hirundapus caudacutus

Rainbow Bee-eater [670] Species or specieshabitat may occur withinarea

Merops ornatus

Black-faced Monarch [609] Species or specieshabitat known to occurwithin area

Monarcha melanopsis

Spectacled Monarch [610] Species or specieshabitat likely to occurwithin area

Monarcha trivirgatus

Satin Flycatcher [612] Species or specieshabitat known to occurwithin area

Myiagra cyanoleuca

Rufous Fantail [592] Species or specieshabitat likely to occurwithin area

Rhipidura rufifrons

Migratory Wetlands Species


Common Sandpiper [59309] Foraging, feeding orrelated behaviour knownto occur within area

Actitis hypoleucos

Great Egret, White Egret [59541] Species or specieshabitat likely to occurwithin area

Ardea alba

Cattle Egret [59542] Species or specieshabitat likely to occurwithin area

Ardea ibis

Ruddy Turnstone [872] Foraging, feeding orrelated behaviour knownto occur within area

Arenaria interpres

Sharp-tailed Sandpiper [874] Foraging, feeding orrelated behaviour knownto occur within area

Calidris acuminata

Curlew Sandpiper [856] Foraging, feeding orrelated behaviour knownto occur within area

Calidris ferruginea

Red-necked Stint [860] Foraging, feeding orrelated behaviour knownto occur within area

Calidris ruficollis

Great Knot [862] Foraging, feeding orrelated behaviour knownto occur within area

Calidris tenuirostris

Double-banded Plover [895] Foraging, feeding orrelated behaviour knownto occur within area

Charadrius bicinctus

Greater Sand Plover, Large Sand Plover [877] Foraging, feeding orrelated behaviour knownto occur within area

Charadrius leschenaultii

Lesser Sand Plover, Mongolian Plover [879] Foraging, feeding orrelated behaviour knownto occur within area

Charadrius mongolus

Latham's Snipe, Japanese Snipe [863] Foraging, feeding orrelated behaviour mayoccur within area

Gallinago hardwickii

Grey-tailed Tattler [59311] Foraging, feeding orrelated behaviour knownto occur within area

Heteroscelus brevipes

Bar-tailed Godwit [844] Foraging, feeding orrelated behaviour knownto occur within area

Limosa lapponica

Black-tailed Godwit [845] Foraging, feeding orrelated behaviour knownto occur within area

Limosa limosa

Eastern Curlew [847] Foraging, feeding orrelated behaviour knownto occur within area

Numenius madagascariensis

Little Curlew, Little Whimbrel [848] Foraging, feeding orrelated behaviour knownto occur within area

Numenius minutus

Whimbrel [849] Foraging, feeding orrelated behaviour knownto occur within area

Numenius phaeopus


Pacific Golden Plover [25545] Foraging, feeding orrelated behaviour knownto occur within area

Pluvialis fulva

Grey Plover [865] Foraging, feeding orrelated behaviour knownto occur within area

Pluvialis squatarola

Painted Snipe [889] Endangered* Species or specieshabitat may occur withinarea

Rostratula benghalensis (sensu lato)

Terek Sandpiper [59300] Foraging, feeding orrelated behaviour knownto occur within area

Xenus cinereus

Listed Marine Species [ Resource Information ]* Species is listed under a different scientific name on the EPBC Act - Threatened Species list.Name Threatened Type of PresenceBirds

Common Sandpiper [59309] Foraging, feeding orrelated behaviour knownto occur within area

Actitis hypoleucos

Magpie Goose [978] Species or specieshabitat may occur withinarea

3.1.3 Sediment transport and beach alignment · 2014. 11. 18. · Project 237236 File...

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