Kempsey Shire Council...2018/12/18 · GHD | Report for Kempsey Shire Council - Stuarts Point...

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Kempsey Shire Council

Stuarts Point Sewerage Scheme

Options Comparison

December 2018

GHD | Report for Kempsey Shire Council - Stuarts Point Sewerage Scheme, 22185121505 | i

Abbreviations

The following Terms and Abbreviations are used in this report.

Term Definition

AS Australian Standard

ADWF Average Dry Weather Flow

BC Act Biodiversity Conservation Act 2016

CHN Chainage

DPE Department of Planning and Environment

EIS Environmental Impact Statement

EPA Environmental Protection Authority

EPBC Act Environment Protection and Biodiversity Conservation Act 1999

ET Equivalent Tenement

FM Act Fisheries Management Act 1994

HDD Horizontal Directional Drilling

HDPE High Density Polyethylene

JRPP Joint Regional Planning Panel

kL Kilolitres

KSC Kempsey Shire Council

LALC Local Aboriginal Land Council

MBR Membrane Bio-Reactor

ML Mega litre

NNTR National Native Title Register

NPW Act National Parks and Wildlife 1974

OEH Office of Environment and Heritage

POEO Act Protection of the Environment Operations Act 1997

PWWF Peak Wet Weather Flow

SBR Sequencing Batch Reactor

SEAR Secretary’s Environmental Assessment Requirements

SEPP State Environmental Planning Policies

SPSS Stuarts Point Sewerage Scheme

SRD State Regional Development

SSD State Significant Development

STP Sewage Treatment Plant

WM Waste Management

WSA Water Services Australia

GHD | Report for Kempsey Shire Council - Stuarts Point Sewerage Scheme, 22185121505 | ii

Table of contents

1. Introduction ............................................................................................................................... 1

1.1 Project background ......................................................................................................... 1

1.2 Aboriginal heritage constraints ......................................................................................... 4

1.3 Design constraints ........................................................................................................... 4

1.4 Other constraints ............................................................................................................. 4

1.5 Aim of report.................................................................................................................... 5

1.6 Limitations ....................................................................................................................... 5

2. Options assessed ...................................................................................................................... 7

2.1 Utilised design data ......................................................................................................... 7

2.1 Refined options assessment ............................................................................................ 7

2.2 Pressure sewer collection network ................................................................................... 7

3. Sewage treatment options ......................................................................................................... 9

3.1 Upgrade of South West Rocks STP (Option 1)................................................................. 9

3.2 Stuarts Point STP (Option 2) ......................................................................................... 12

3.3 Treated effluent disposal ............................................................................................... 13

3.1 Recommended buffer distances .................................................................................... 14

4. Sewage transfer route options ................................................................................................. 16

4.1 Northern Transfer via Shark Island and Quarry Street (Option 1A) ................................. 16

4.2 Northern Transfer via Shark Island and New Entrance (Option 1B) ................................ 19

4.3 Southern transfer via Lindsay’s Trail and New Entrance (Option 1C).............................. 20

4.4 Rising Main from Fishermans Reach to Stuarts Point STP (Option 2A) .......................... 21

5. Project risks ............................................................................................................................ 23

5.1 Sea level rise................................................................................................................. 23

5.2 HDD Crossing ............................................................................................................... 23

5.3 Location of new STP and effluent disposal..................................................................... 24

5.4 Key environmental constraints ....................................................................................... 24

6. Environmental and planning review ......................................................................................... 25

7. Comparison of options ............................................................................................................ 32

7.1 Multi Criteria assessment .............................................................................................. 32

7.2 Cost Estimates .............................................................................................................. 41

8. Conclusions and recommendations ......................................................................................... 42

8.1 Conclusions .................................................................................................................. 42

8.2 Recommendations ........................................................................................................ 44

8.3 References .................................................................................................................... 44

GHD | Report for Kempsey Shire Council - Stuarts Point Sewerage Scheme, 22185121505 | iii

Table index

Table 3-1 Load Predictions for South West Rocks STP ................................................................... 9

Table 3-2 South West Rocks Treatment Plant Capacity ................................................................... 9

Table 3-3 Site Controls for Use of Effluent ..................................................................................... 15

Table 3-4 Buffer Distances to Effluent Disposal Area ..................................................................... 15

Table 6-1 Summary of Approval Considerations ............................................................................ 27

Table 6-2 Preliminary Legislation Review ...................................................................................... 28

Table 7-1 MCA Ranking Table ...................................................................................................... 33

Table 7-2 Low Pressure System Costs .......................................................................................... 41

Table 7-3 Transfer System Options Costs ..................................................................................... 41

Table 7-4 Treatment Options Costs ............................................................................................... 41

Table 7-5 Total Project Costs for Each Option ............................................................................... 41

Figure index

Figure 1 Service Lots .................................................................................................................... 2

Figure 2 Proposed Options ............................................................................................................ 3

Figure 3 Sewage Treatment Options ........................................................................................... 10

Figure 4 Sewage Transfer Options .............................................................................................. 17

Appendices

Appendix A – Environmental Constraint Mapping

Appendix B – Cost Estimates

GHD | Report for Kempsey Shire Council - Stuarts Point Sewerage Scheme, 22185121505 | 1

1. Introduction

1.1 Project background

GHD Pty Ltd (GHD) has been engaged by Kempsey Shire Council (Council/KSC) to undertake

investigations relating to design of a reticulated sewerage system to serve the Stuarts Point

area. The project proposes to install a sewerage system that services the villages of Grassy

Head, Stuarts Point and Fishermans Reach (Figure 1).

GHD undertook a preliminary options assessment for catchment sewage reticulation, routes for

sewage transfer pipelines and locations based on the hydraulic design criteria established in

Stuarts Point Sewerage Scheme Preliminary Design Report (GHD, 2017).

Due to the cultural heritage significance of the locality and potential for environmental impacts

associated with construction, several route options were developed for the transfer pipeline for

discussion with key stakeholders.

The original alignment routes assessed by GHD are provided as Figure 2.

Golden Hole

StuartsPointVillage

Grassy HeadHoliday Park

Stuarts PointHoliday Park

FishermansReach Village

Stuarts PointConventionCentre

YarrahapinniAdventistYouth Centre

FISHERMANSREACH

YARRAHAPINNI

SOUTH WESTROCKSRAINBOWREACH

ARAKOON

BARRAGANYATTI

GRASSY HEAD

JERSEYVILLE

CLYBUCCA

STUARTS POINT

WAY WAY

© Department of Finance, Services & Innovation 2018

Figure 1

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0 560 1,120 1,680 2,240280

Metres

LEGEND

© 2018. Whilst every care has been taken to prepare this map, GHD, LPI and KSC make no representations or warranties about its accuracy, reliability, completeness or suitability for any particular purpose and cannot accept liability and responsibility of any kind (whether in contract, tort or otherwise) for any expenses, losses, damages and/or costs (including indirect or consequential damage) which are or may be incurred by any party as a result of the map being inaccurate, incomplete or unsuitable in any way and for any reason.

Job Number

Revision 0

22-185121505

Date 06 Dec 2018oKempsey Shire Council

Stuarts Point Sewage SystemOptions Assessment Report

Serviced lots

Data source: KSC: Aerial/Cadastre, 2016. LPI:DTDB, 2015. Created by: kpsroba

Level 3, GHD Tower, 24 Honeysuckle Drive, Newcastle NSW 2300 T 61 2 4979 9999 F 61 2 4979 9988 E [email protected] W www.ghd.com.au

Map Projection: Transverse Mercator

Horizontal Datum: GDA 1994

Grid: GDA 1994 MGA Zone 56

Paper Size A4

Study area

To be serviced as part ofcurrent project

Proposed future servicedlots - Rural Residential

Proposed future servicedlots - based upon currentLEP

Cadastre

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HDDoption 2

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TransferStation 1

TransferStation 2

TransferStation 3

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FISHERMANSREACH

KEMPSCORNER

GRASSY HEAD

STUARTS POINT

ARAKOON

SOUTH WESTROCKS

497,500

497,500

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0 0.4 0.8 1.2 1.6 2

Kilometres

LEGEND

© 2018. Whilst every care has been taken to prepare this map, GHD and LPI make no representations or warranties about its accuracy, reliability, completeness or suitability for any particular purpose and cannot accept liability and responsibility of any kind (whether in contract, tort or otherwise) for any expenses, losses, damages and/or costs (including indirect or consequential damage) which are or may be incurred by any party as a result of the map being inaccurate, incomplete or unsuitable in any way and for any reason.

Job Number

Revision 0

22-185121505

Date 06 Dec 2018oKempsey Shire CouncilStuarts Point Sewerage SystemOptions Assessment Report

Preliminary alignment options

Data source: LPI: DTDB / DCDB, 2012, Aerial Imagery, 2016; GHD: Proposed Infrastructure (2017). Created by: fmackay





Paper Size A4

! Locality Point

Cadastre

Preliminary options

Reticulation mains

Transfer mains

HDD crossing option 1




Rising main option

[Ú Transfer WWPS

"J Launch pits

Service Layer Credits: © Department of Finance, Services & Innovation


1.2 Aboriginal heritage constraints

Following stakeholder discussions and assessment by a heritage consultant, Aboriginal heritage

constraints were identified for the preliminary route options as outlined below.

Option 1 - Office of Environment and Heritage (OEH) and Kempsey Local Aboriginal

Land Council (LALC) advised that the Option 1 was inappropriate due to the overall

cultural significance of Shark Island.

Option 2 – The Fishermans Reach Road to Lindsay’s Trail section is in the vicinity of the

Stuarts Point Midden and areas where Aboriginal skeletal remain have been repatriated

by the OEH. Local Aboriginal groups noted strong opposition to any design that would

traverse this location (including Options 2 and 3).

Option 3 - The elevated lands at Rainbow Reach and the entry point to South West

Rocks would require additional archaeological investigation in the form of test pit

excavations. The Spencers Creek Midden and the Spencers Creek Quarry site are

recorded in close proximity to this alignment.

Option 4 - The exit point at Pelican Island has the potential to contain Aboriginal midden,

however the likelihood of encountering midden is less than Option 3. The elevated sand

dune crossing at Rainbow Reach would require additional archaeological investigation in

the form of test pit excavations.

1.3 Design constraints

The key design challenge identified in the preliminary investigations related to the alignment

between New Entrance road and Keith Andrew Avenue, an elevated section along the route

with several peaks near the South West Rocks STP. This profile presented hydraulic challenges

in the form of negative system pressures or alternatively return to gravity network, for a section,

with associate odour release potential in close proximity to residential areas.

Other design constraints included:

Constructability concerns with the proposed horizontal direction drilling (HDD) under

Macleay River on the grounds of potential for sewage transfer security, environmental

impact, cost and time to project.

Integrating the New Entrance Area into the transfer system as the area currently drains to

the north and integration into the alignment will require reversal of the system (at least the

northern part to the higher area to the southern end of the New Entrance area.

1.4 Other constraints

Loss of opportunity to allow effluent reuse for crop irrigation.

Extraction of water from the groundwater catchment for the Stuarts Point bores.

Cost implications of utilisation of the available capacity at the existing South West Rocks

Sewage Treatment Plant (STP) and the potential to bring forward a significant plant

upgrade.

Construction activity within the study area would be subject to an environmental approval

process, which depending on the construction and operational impacts of the selected

design may involve a lengthy assessment, approvals and permitting process.


1.5 Aim of report

As a result of the potential design challenges and stakeholder concerns with the original

preliminary alignment, Council has decided to revisit the previously considered options of

sewage transfer main to SWR STP.

The aim of this report is to revise the options assessment to include the following:

Broaden the review of options for providing sewerage service to Stuarts Point, including

provision of new STP on the western side of Macleay River, near Stuarts Point and

associated options for effluent discharge. (This option was not reviewed in the previous

options assessment).

Review the treatment capacity of the existing South West Rocks STP and comment on

upgrades that may be triggered as a result of the Stuarts Point Sewerage Scheme

(SPSS).

Refinement of Macleay River Crossing options:

– Southern route from Lindsay Trail via Rainbow Reach to New Entrance and South

West Rocks.

– Northern route via Shark Island to New Entrance, South West Rocks.

Prepare cost estimates suitable to support the comparison of the options.

Prepare a multi-criteria analysis of the options to provide a basis for identification of the

best option on balance for the community given the environmental, social and economic

impacts.

Based on this analysis, GHD will recommend and option to proceed to concept

development, ground proofing and field investigations.

1.6 Limitations

This report: has been prepared by GHD for Kempsey Shire Council and may only be used and

relied on by Kempsey Shire Council for the purpose agreed between GHD and the Kempsey

Shire Council as set out in Section 1.1 of this report.

GHD otherwise disclaims responsibility to any person other than Kempsey Shire Council arising

in connection with this report. GHD also excludes implied warranties and conditions, to the

extent legally permissible.

The services undertaken by GHD in connection with preparing this report were limited to those

specifically detailed in the report and are subject to the scope limitations set out in the report.

The opinions, conclusions and any recommendations in this report are based on conditions

encountered and information reviewed at the date of preparation of the report. GHD has no

responsibility or obligation to update this report to account for events or changes occurring

subsequent to the date that the report was prepared.

The opinions, conclusions and any recommendations in this report are based on assumptions

made by GHD described in this report. GHD disclaims liability arising from any of the

assumptions being incorrect.

GHD has prepared this report on the basis of information provided by Kempsey Shire Council

and others who provided information to GHD (including Government authorities)], which GHD

has not independently verified or checked beyond the agreed scope of work. GHD does not

accept liability in connection with such unverified information, including errors and omissions in

the report which were caused by errors or omissions in that information.


The opinions, conclusions and any recommendations in this report are based on information

obtained from, and testing undertaken at or in connection with, specific sample points. Site

conditions at other parts of the site may be different from the site conditions found at the specific

sample points.

GHD has prepared the preliminary cost estimate provided using information

reasonably available to the GHD employees who prepared the estimate; and based on

assumptions and judgments made by GHD.

The Cost Estimate has been prepared for the purpose of order of cost estimate and must not

be used for any other purpose. The Cost Estimate is a preliminary estimate only. Actual prices,

costs and other variables may be different to those used to prepare the Cost Estimate and may

change. Unless as otherwise specified, no detailed quotation has been obtained for actions

identified in this estimate. GHD does not represent, warrant or guarantee that the options

assessed can or will be undertaken at a cost which is the same or less than the Cost Estimate.

Where estimates of potential costs are provided with an indicated level of confidence,

notwithstanding the conservatism of the level of confidence selected as the planning level, there

remains a chance that the cost will be greater than the planning estimate, and any funding

would not be adequate. The confidence level considered to be most appropriate for planning

purposes will vary depending on the conservatism of the user and the nature of the project. The

user should therefore select appropriate confidence levels to suit their particular risk profile.


2. Options assessed

2.1 Utilised design data

In developing the options included in this assessment report, GHD reviewed and utilised the

following data provided by KSC for the calculations undertaken during the hydraulic analysis

and sizing of pump station, transfer pipelines and low pressure systems.

Water Production Weekly (Weekly/Monthly)

2015 Metered Consumption Data for Stuarts Point

Water Consumption Peaking Analysis

South West Rocks Options for Upgrade Strategies Report (GHD, 2002)

2.1 Refined options assessment

Treatment and Effluent Disposal Options

The STP location and effluent disposal options included within this report comprise:

Option 1 - Existing South West Rocks STP site, originally specified as the point for

treatment in previous investigations. Treated effluent is disposed at a dunal discharge

point at New Entrance.

Option 2 - A new Stuarts Point STP site as an alternative. Treated effluent disposal

options considered within this option included subsurface infiltration at the proposed site

or new dunal discharge point northeast of the Stuarts Point village.

Sewage Transfer Options

The selected sewage transfer system, depends largely upon the final location of the STP site

with the options summarised as follows:

South West Rocks STP

Option 1A – Northern Crossing of Macleay River from Perret Lane to Quarry Street

Option 1B - Northern Crossing of Macleay River from Perret Lane to New Entrance Road

Option 1C – Southern Crossing of Macleay River from Lindsay’s Trail to New Entrance

RoadC

Stuarts Point STP

Option 2A - Rising Main from Fishermans Reach to Stuarts Point STP (no Macleay River

crossing)

2.2 Pressure sewer collection network

2.2.1 Low Pressure System

The local area low pressure collection network for each community (Grassy Head, Stuarts Point,

and Fishermans Reach) will remain common to all options and has already been developed to a

suitable level for the options comparison. Accordingly, the project description, layouts and cost

estimates for this portion of the scheme will be adopted as they currently stand. As this scope

will not provide differentiation between the options, it will not have a significant role in the

assessment, but will be included in the final project description, layouts and cost estimates.


2.2.2 Alternative Collection Systems

Whilst design investigations to date have focused on low pressure sewerage technology,

vacuum sewerage is a potential alternative.

One of the key differentiators between low pressure and vacuum sewerage is the suitability of

the systems for staging and flexibility of development. With vacuum sewerage, significant

upfront cost is associated with the vacuum sewage pump station, which cannot be staged.

However the costs associated with provision of services at the house lot are relatively cost

effective.

For low pressure, the infrastructure required at each household is a significant portion of the

total system cost, however this is readily staged and can be provided progressively as

development occurs. Accordingly, vacuum sewage tends to be better suited to communities

approaching full development, whilst low pressure is better suited to communities in the earlier

stages of development allowing the cost effective initial implementation of a sewerage scheme

whilst being able to cater for future development needs.

Low pressure provides other advantages such as reduced infiltration (limited to the house drain

only) and the capacity to use the provided storage to manage the peak flows in the collection

system.

Given the above, low pressure sewerage is considered a more suitable option for the Stuarts

Point Sewerage Scheme however alternate submissions will be considered at the tender stage

(including vacuum or a combined vacuum/pressure combination).


3. Sewage treatment options

The sewage treatment plant options and effluent disposal options considered in this report

(existing and alternate) are shown over (Figure 3).

3.1 Upgrade of South West Rocks STP (Option 1)

In order to identify the criteria required and scoring for assessment, it is imperative to

understand the current loads and ultimate design capacities of the existing South West Rocks

STP.

Table 3-1 shows the sewage load predictions used for the hydraulic analysis. This data was

based on simplified design flow calculations (GHD 2017).

Table 3-1 Load Predictions for South West Rocks STP

2016 2020 2030 2036

SOUTH WEST ROCKS Base

Population 5310 5612.4 6769 7660

ADWF (ML/day) 1.118 1.18 1.43 1.61

SOUTH WEST ROCKS Tourist

Population 2655 2806 3384 3830

ADWF (ML/day) 0.547 0.58 0.7 0.79

SOUTH WEST ROCKS Combined

Population 7965 8418 10153 11490

ADWF (ML/day) 1.665 1.76 2.13 2.4

Stuarts Point Sewerage Scheme

Population 1888 - - 3305

ADWF (ML/day) 0.72 - - 1.27

Combined Total - -

ADWF (ML/day) 2.39 - - 3.67

Table 3-2 South West Rocks Treatment Plant Capacity

Year Plant Capacity (ML/day)

1980 1.44

2022 2.55

2033 2.55

r]

r]

FISHERMANSREACH

YARRAHAPINNI

SOUTH WESTROCKSRAINBOWREACH ARAKOON

BARRAGANYATTI

GRASSY HEAD

JERSEYVILLE

CLYBUCCA

STUARTS POINT

WAYWAY

Figure 3

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Job Number

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22-185121505


Revised treatment options






Paper Size A4

Option 1

r] Existing South West Rocks STPSWR new entrance effluent disposal

Option 2

r] New Stuarts Point STPProposed effluent pipeline

Offsite effluent disposal

HDD

Onsite subsurface effluent disposal

Proposed Treatment Plant Site

Cadastre

r]

STUARTS POINT

SECON

DAVEN

UE

OCEAN AVENUE

MARIN

EPARAD

E

FI SHERMANS REACH ROAD

Service Layer Credits: © Department of Finance, Services & Innovation 2018

Option 2


The South West Rocks STP is currently sized to handle 2.55 ML/day which includes the

Pasveer channels. This means that the existing plant is capable of treating the current

combined loads (SPSS and South West Rocks (2.4 ML/day)), however a plant upgrade would

be required in the short term due to the ultimate South West Rocks flows exceeding the current

plant capacity. Based on the combined loading, GHD predict the capacity limit to be reached

around 2022 (refer graph below). Considering the approximate lead time of at least two years to

upgrade a STP, commencement of design of construction works would be required by 2020.

If Council adopt Transfer Option 1A, 1B or 1C, an upgrade would be required to ensure the STP

is capable of handling flows above the ‘Combined 2036 Flow’ (assumed as ultimate) with

sufficient overhead capacity. A total of 3.8 ML/day ADWF (increase of 1.3 ML/day) capacity is

therefore recommended to accommodate the ultimate flow of both South West Rocks and

Stuarts Point areas.

South West Rocks STP Capacity

As a result of undertaking this high-level capacity assessment, it is recommended that Council

undertake the following actions in order to fully understand the future requirements for South

West Rocks STP:

Commence a raw sewage characterisation program to assess the sewage quality, in both

tourist and non-tourist periods

Undertake sampling of supernatant from sludge lagoons

Investigate population projections for SPSS

Liaise with the Environmental Protection Authority (EPA) to determine requirements for

licence upgrades to address increased flows

Investigate upgrade options for liquid and solid streams


3.2 Stuarts Point STP (Option 2)

This option is premised on the approach of forgoing the transfer to South West Rocks STP by

constructing a new treatment plant south of Stuarts Point. Potential sites considered for a new

plant comprise (subject to required buffer zones from adjacent residents):

Lot 213 DP 752438 – Vacant Crown land

The Council waste management site (Lot 93 DP 752438) was originally considered but

discounted as an option based on the proximity to residences.

3.2.1 Sewage Collection

With the proximity of Fishermans Reach to the proposed Stuarts Point STP site, it is envisaged

that the Fisherman’s reach low pressure system (2.2.1) would be capable of discharging to the

inlet of the STP via a short rising main using the capacity of the onsite pump units. This

assumption would need to be validated in subsequent design stages.

3.2.2 Sewage Treatment

The ultimate capacity of a new STP to service the ultimate populations for the Grassy Heads,

Stuarts Point and Fishermans Reach Area would be approximately 1.3 ML/day ADWF (refer

Table 3-1). The required treatment plant process would be dependent upon the selected

effluent disposal and the minimum required effluent quality necessary for environmental

licencing of the disposal. The most likely treatment processes considered are:

Sequencing Batch Reactors (SBR) with or without effluent polishing via filtration (cloth or

sand filtration) or,

Membrane Bioreactor.

Both treatment options are modular and have the ability to increase capacity if required in the

future. As such, both options should be considered at this stage. Selection of a treatment

process design would require further assessment of licencing requirements (e.g. proposed

effluent disposal and required effluent quality). Infrastructure would include effluent storage,

chlorination, transfer pump station and effluent transfer pipeline.


3.3 Treated effluent disposal

The identified opportunities for effluent disposal area are as follows:

3.3.1 South West Rocks STP

Dunal Disposal

The existing South West Rocks STP utilises a dunal effluent disposal area at New Entrance.

3.3.2 Stuarts Point STP

Option 2A- Subsurface Infiltration

A subsurface infiltration system within the treatment plant site was proposed by Council due to a

potentially easier approvals pathway with one contaminated land area and lower cost of

construction. However, due to the area infiltration area required (approx. 4 hectares or greater

for the ultimate 1.5 ML/day, assuming high permeability sandy soils and adequate drainage

capacity), this option may limit the available land area for treatment plant infrastructure.

Additionally, the infiltration site does not provided the acceptable EPA required buffer zones

from residents and bore water supply.

Option 2B - Dunal Disposal

A potential site, similar to the South West Rocks dunal disposal, has been identified (at a

desktop level) on the eastern side of the Macleay Arm, north east of the Stuarts Point township.

The pressure main for effluent disposal could be installed in a combined trench with the Stuarts

Point sewage rising main to a suitable point on Marine Parade. A horizontal directional drill

under the Macleay Arm would then be installed onto Lot/Plan 7300//DP1152758 for disposal

(refer Figure 3).

The infrastructure required would consist of the following elements:

Effluent storage and outfall pump station at the STP site

Effluent pipeline constructed via common trench with the sewage rising main and HDD

under the Macleay Arm

Effluent irrigation disposal area on the foredunes

For the basis of this options assessment and cost estimates, GHD has estimated preliminary

costs of the more conservative dunal disposal option due to the compliance with EPA buffer

zones and unreserved land area for disposal.


Ocean

An ocean outfall is an alternative effluent disposal option. However, this option was not

developed further during this options assessment. Marine discharge of treated effluent would

require the following elements:

Effluent storage and outfall pump station at the STP site (No requirement for wet weather

storage)

Effluent pipeline

A HDD outfall to an approved discharge point

Implementation of a sea floor effluent diffuser inclusive of near field dispersion modelling

Effluent Reuse

There is an opportunity for effluent reuse for irrigation of commercial avocado plantations at

Fishermans Reach. At this stage, there is no specific requirements for effluent reuse, however

this may be a potential condition in the environmental licencing process.

It is noted that KSC will not be able to directly control the timing and quantity of effluent reuse

onto third party properties. Accordingly, effluent reuse will be opportunistic, targeted at diverting

a portion of the effluent from the disposal system, rather than a standalone disposal option in its

own right.

Developing a recycled water management system is dependent upon the outcomes of a risk

assessment and mitigation process. This process takes into account the treatment process, end

use (i.e. crops irrigated), treatment barriers and non-treatment barriers. However it is noted that

for ocean or dunal effluent disposal options, a high quality effluent would be required, and as

avocados are a peeled crop, the extent of effluent treatment required to meet the target

recycled water quality may not be significantly more than required for disposal.

No consultation with stakeholders has been undertaken in the preparation of this report

regarding the effluent irrigation demands, quality, assessment of impacts to groundwater,

requirements for avocado crops, or other opportunities for effluent reuse at this stage.

3.1 Recommended buffer distances

A buffer zone is an area of land or water surrounding a particular land use (STP or effluent re-

use area) which is used to minimise adverse environmental and social impact due to odour,

noise, visibility or biological hazards of the land use. The buffer zone provides an important role

in reducing the impacts to ‘acceptable levels’.

3.1.1 Buffer Zone for STP

Department of Planning recommends a minimum buffer of 400 m width around STPs, although

this may be varied to suit local conditions (Department of Planning Circular No. 148 (E3) -

“Guidelines for buffer areas around sewage treatment (water pollution control) plants”).

Draft NSW Best Practice Odour Guidelines (which were written to replace the Department of

Planning Circular – but never adopted) also has a recommended 400 m buffer.

Chapter 6 of the NSW Department of Primary Industries Living and Working in Rural Areas

handbook provides recommended minimum buffer distances for various types of development

including waste facilities and sewerage works. The recommended buffers for STPs are 400 m.


3.1.2 Buffer Zone for Effluent Re-use

The Australian guidelines for Water Recycling: Managing Health and Environmental Risks

(2006) outlines the following site controls for designated uses of recycled water from treated

sewage.

Table 3-3 Site Controls for Use of Effluent

Application On Site preventive measures

Municipal use — open spaces, sports grounds, golf courses, dust suppression, etc. or unrestricted access and application

No specific measures

Municipal use, with restricted access and application

Minimum 25-30 m buffer to nearest point of public access

Municipal use, with enhanced restrictions on access and application

Minimum 25-30 m buffer to nearest point of public access

Landscape Irrigation Combinations of

Micro spray

Drip irrigation

No public access

Commercial food crops consumed raw or unprocessed

None required, although pathogen reduction will occur between harvesting and sale

Commercial food crops No access during irrigation and if spray irrigation, minimum 25–30 m buffer distance between irrigation area and nearest public access point

Additionally, NSW Environmental guidelines: Use of effluent by irrigation, provides buffer zones

from effluent irrigation areas to minimise adverse effects to adjacent natural water course,

ecosystems, and residential wells or bore water supplies.

Table 3-4 Buffer Distances to Effluent Disposal Area

Sensitive Area Separation Distance (medium to high strength effluent)

Natural waterbodies (e.g. rivers and lakes) 50 m

Other Waters Site-Specific

Domestic well for house water supply 250 m

Town water supply bores 1000 m

Residential Area subject to spray drift 50 m

Drinking Water Catchments, Aquatic Ecosystems etc.

250 m


4. Sewage transfer route options

The following section provides a detailed description of the three sewage transport systems

considered in this Options Assessment (refer previous section). Transfer options 1A, 1B and 1C

are compatible with treatment Option 1 only. Transfer option 2A (refer to section 1.2) is

compatible with treatment 2 only. It should also be noted that Options 1A,1B and 1C provide the

added benefit of a new trunk main which achieves Council’s future initiative to augment the

sewage trunk main on the South West Rocks side to serve future development areas.

4.1 Northern Transfer via Shark Island and Quarry Street (Option

1A)

Option 1a is the northern crossing of Macleay River from Perrett Lane to Quarry Street. This

option will maintain the alignment and infrastructure north of Perrett Lane servicing Grassy

Heads, Stuarts Point and Fishermans Reach identical to that proposed in Option 2.

Option 1A- Northern Transfer via Shark Island and Quarry Street

4.1.1 Description

At Perrett Lane, a HDD would pass under Macleay Arm from west of Fishermans Reach

Road to a suitable exit point to be confirmed on the south western side of Shark Island

(possible location adjacent to existing track on Macleay Arm side).

From the HDD exit point, another HDD section would pass under the Macleay River to a

point in Quarry Street road reserve. In order to minimise the extent of disturbance on

Shark Island, the HDD works would limit the surface construction works area to a single

site containing HDD exit pits and necessary connecting pipework.

r]

r]

FISHERMANSREACH

YARRAHAPINNI

SOUTH WESTROCKSRAINBOWREACH ARAKOON

BARRAGANYATTI

GRASSY HEAD

CLYBUCCA

STUARTS POINT

WAY WAY

© Department of Finance, Services & Innovation 2018

Figure 4

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r] Existing South WestRocks STPr] New Stuarts Point STP

Cadastre Transfer route options

Option 1A

Option 1B

Option 1C


From the HDD exit point, the pipeline route would follow the northern side of Quarry

Street and turn south on the eastern side of Tahlee Close/pedestrian route to Gordon

Young Drive.

The route then follows Gordon Young Drive to Hill Street, through to the South West

Rocks golf course. Alternatives routes include options along Gregory Street and Mitchell

Street, however preliminary review indicates similar high point hydraulic challenges for

these options.

The pipeline would then cross the golf course to the eastern side, either directly across

the course, or following the northern boundary.

There are existing infrastructure corridors on the eastern side of the golf course linking to

the South West Rocks STP. Where possible the alignment would be located in existing

infrastructure corridors.

4.1.2 Challenges

Risks associated with HDD in, or near, environmentally sensitive areas.

Shark Island has been advised to be an area of Aboriginal cultural significance and may

contain artefacts.

KSC access for operating and maintaining infrastructure on Shark Island would be

limited, particularly for elements such as pump stations should they be proposed on the

island.

Provision of power supply for pumps on Shark Island may be challenging.

As Ocean Street follows the ridge line, the exit point will be subject to the profile that can

be achieved as follows:

– If a suitable steep exit angle can be achieved on the slope to the ridge, an exit in the

road reserve, to the west of Ocean Street, may be possible without impacting access

to residences.

– If not, a suitable exit on the northern side of Quarry Street to the east of Ocean Street

would be adopted.

– Along this corridor there is a north-south ridge to be crossed between Gregory Street

and Mitchell Street, with Sturt Street being the approximate high point. The elevation

of this ridge is above the system hydraulic grade line, resulting in negative pressures

unless an air break is provided. However, provision of an air break would provide

turbulent partial full pipe flow conditions on the downstream side of the ridge and

potential for significant odour release.

– This is a similar challenge as occurs with the Option 1C alignment, however the ridge

is narrower with the highest elevation approximately 15 m AHD, rather than multiple

ridges with peaks in excess of 30 m AHD.

– Options to resolve these hydraulics would be to HDD under the ridge line for

approximately 300 to 500 m, or alternatively providing an air break at the high point

with the associated odour release challenges that would exist.

– HDD additional cost (estimate ~ ).

– Air break ~Discharge maintenance hole (MH) complete with odour scrubber and

gravity sewer to the transition point back to full pipe flow (MH ~ , odour control

, extra over for sewer

). Higher risks in terms of odours, air locking and settlement

of solids.


4.2 Northern Transfer via Shark Island and New Entrance

(Option 1B)

Option 1b - Northern Transfer via Shark Island and New Entrance

4.2.1 Description

The proposed infrastructure for this option would be very similar to Option 1A north of

Perrett Lane.

At Perrett Lane, a short HDD is proposed to pass under Macleay Arm from west of

Fishermans Reach Road to a suitable exit point to be confirmed on Shark Island (possible

location to the north/northwest of the Shark Island Jetty, adjacent an existing track).

From the exit point, another HDD section would pass under the Macleay River to a point

in New Entrance road reserve. In order to minimise the extent of disturbance on Shark

Island, the HDD works would limit the surface construction works area to a single site

containing HDD exit pits and necessary connecting pipework.

From the exit point, the pipeline would be trenched along Marlin Drive, Gilbert Cory Street

and along Keith Andrews Avenue to the South West Rocks STP.

Trenching on Shark Island was removed due to concerns regarding disturbance of

cultural sensitive land.

4.2.2 Challenges

Risks associated with HDD in, or near, environmentally sensitive areas.

Shark Island has been advised to be an area of high Aboriginal cultural significance and

may contain artefacts.

KSC access to infrastructure on Shark Island would be limited, particularly for elements

such as pump stations should they be proposed on the island.

Availability of power supply for pumps on Shark Island is also limited.


At approximately CH 16,750 , the route of the transfer pipeline reaches a high point of

43 m AHD in Keith Andrews Drive, just under 2 km from the South West Rocks STP. This

presents a number of technical challenges including:

– Potential for negative pressures, unless the high point is effectively ventilated (e.g.

provision of a standpipe).

– Potential for release of odours, as the sewage will be septic, with potential impact on

adjacent residential development.

– With an elevated inlet at the South West Rocks STP, flow will need to be returned to

pressure flow conditions, either by collection in a wet well and re-pumping or a natural

transition to pressure flow in the pipe line. Should transition in the pipeline be adopted

there would be potential for air entrainment, flow surging and release of entrained

gasses under pressure at the STP inlet.

– The two potential approaches for the design of the transfer system under these

conditions are either traditional sewer complete with manholes or a closed pipe at

grade with provision of a vent at high points. The advantages and disadvantages of

these options are detailed in the Stuarts Point Sewerage Scheme Preliminary Design

Report (GHD, 2017).

4.3 Southern transfer via Lindsay’s Trail and New Entrance

(Option 1C)

Option 1C comprises a southern crossing of the Macleay River from Lindsay’s Trail to New

Entrance Road/Marlin Drive. The sewage transfer main would be constructed via HDD (refer to

the Stuarts Point Sewerage Scheme Preliminary Design Report (GHD, 2017).

Option 2 – Southern transfer via Lindsay’s Trail and New Entrance


4.3.1 Description

The proposed infrastructure for this option would be very similar to Option 1 north of

Perrett Lane south of Fishermans Reach.

The sewage transfer main will extend south of Fishermans Reach up to Lindsay trail.

A HDD would be proposed to pass under Macleay River and Rainbow Reach to a

suitable exit point on New Entrance road at South West Rocks.

If a suitable steep exit angle can be achieved on the slope to the ridge, an exit in the road

reserve to the west of Ocean Drive may be possible without impacting access to

residences.

From the exit point, the pipeline would be trenched along Marlin Drive, Gilbert Cory Street

and along Keith Andrews Avenue to the South West Rocks STP.

4.3.2 Challenges

The alignment is in the vicinity of the Clybucca-Stuarts Point midden complex. Opposition

to this alignment has been received from NPWS and the Aboriginal community.

The Council easement along Lyndsay’s Trail is surrounded by (and includes a short

section within) National Park estate.

The remaining challenges following the HDD crossing are as per to Option 1b at approximately

CHN 16,670 (see Section 4.3.2)

4.4 Rising Main from Fishermans Reach to Stuarts Point STP

(Option 2A)

This option is only required if the Option 2 Stuarts Point STP is selected. The common transfer

route from Grassy Heads and Stuarts Point can be adopted with a new rising main from

Fishermans Reach north into the proposed STP inlet works.

4.4.1 Description

The proposed infrastructure for this option would be very similar to all aforementioned

options, until the proposed location of the new treatment plant (see red line in Option 3

below).

The low pressure trunk main at Fishermans Reach can be extended to divert flows north

towards to the new Stuarts Point STP.

4.4.2 Challenges

Since Option 2A does not transfer SPSS loads to South West Rocks, the opportunity to

upgrade the South West Rocks transfer main upgraded concurrently during the SPSS

project would be lost. As there will be an eventual need for the upgrade, this would need

to be packaged by Council as a separate scope of works.


Option 2A – Fishermans Reach to Stuarts Point STP


5. Project risks

5.1 Sea level rise

In order to future proof the infrastructure that would be delivered under the project,

consideration should be given to the potential range of sea level rise and the impacts that this

may have on the serviceability of the infrastructure.

The nominal sea level rise shall be confirmed with Council to ensure the assets are designed for

the required design life.

The impact of the sea level rise is anticipated to include an increased risk (including saline tidal

inundation or elevated flooding levels) and frequency of inundation occurring.

In terms of impact, inundation, saline or otherwise is not anticipated to have an impact of

concern in respect of the proposed HDPE rising mains. Consideration however should be given

to the careful selection of metallic components (bolts, nuts and backing rings) to ensure a

suitable durability, in the event of saline impacts.

Pump stations however are potentially prone to increased flooding levels and salinity

deterioration. Accordingly it is recommended for pump stations that:

Top of pump station is set above tide and flood levels by the anticipated sea-level rise

Concrete elements such as wet wells are provided with suitable concrete grades and

covers to provide appropriate durability under saline exposure conditions

The level of sea level rise to be accommodated will need to be assessed in consultation with

KSC based on available research data.

5.2 HDD Crossing

Any HDD crossing of the Macleay River or Macleay Arm represents a critical element of the

infrastructure with significant impacts should the pipeline fail in service.

The highest risk time is during the construction of the pipeline, particularly during pull back of

the pipeline into the drill in the last phase of the installation process. After this point the stresses

in the pipeline, and the associated failure risks, reduce rapidly due to the stress creep property

of the pipe. After the first few weeks/months after installation, the risks are reasonably assessed

as low, although there will always be some remaining risk.

The impact of a HDD pipeline failure includes the release of contaminants to the environment,

potentially for a significant period until a repair/replacement can be implemented and/or a

significant period of loss of service.

The options to mitigate this risk are:

Provision of a HDD enveloping pipe of larger diameter than the proposed carrier pipe, to

enable insertion. This option would have little or no impact on the likelihood of a pipeline

failure, however it may reduce the extent of contaminant release to the environment and

potentially the time duration required to undertake a repair subject to the lead time

required to access the necessary replacement pipe quickly. The key implications of this

option is that it would more than double construction costs. No allowance has been made

in the cost estimates to address this risk at this stage.


Provision of a second HDD crossing:

– Again this option would not change the likelihood of a pipeline failure or the extent of

the contaminant release in the first instance. However the availability of a second

pipeline would facilitate a faster response to an incident and therefore mitigate the

duration of the loss of service and the total contaminant release to the environment.

Key implications of adopting the option is that it will nearly double the cost of the HDD

crossing works. No allowance has been made in the cost estimates to address this

risk at this stage.

5.3 Location of new STP and effluent disposal

The provision of a STP at Stuarts Point has the benefit of eliminating the need for a HDD

sewage transfer pipeline and associated risks. However when locating effluent irrigation areas,

it is essential to ensure the neighbouring sensitive environments are considered and the

required buffer distances (as nominated by EPA) are maintained. Considering the proximity to

natural water courses, drinking water bores and residential areas within the study area, this

option would therefore add the following potential risks:

Insufficient buffer zones for onsite effluent disposal

Adequate management of buffer zones

Contaminant release from a new STP

5.4 Key environmental constraints

Based on a review of licenced and publically available mapping, the key environmental

constraints for all options are:

Aboriginal heritage

Coastal wetlands

State and Commonwealth listed threatened species, populations and/ or communities

National Park estate

Acid sulfate soils

Scenic protection lands

Available mapping of environmental constraints above is provided in Figure 5, 6 and 9 in

Appendix A. Further discussion of the associated environmental planning approval requirements

is provided in Section 6.


6. Environmental and planning review

6.1.1 Planning Approval Pathway

The Environmental Planning and Assessment Act 1979 (EP&A Act) is the principal planning

legislation in NSW. Planning instruments are made under Part 3 of the EP&A Act. Several

instruments define the approval pathway based on a number of factors such as development

location, capital investment value, type of development etc. The most applicable planning

instruments are discussed below.

State Environmental Planning Policy (Infrastructure) 2007

State Environmental Planning Policy (Infrastructure) 2007 (ISEPP) aims to facilitate the effective

delivery of infrastructure across the state through increased regulatory certainty and improved

efficiency and flexibility in the location of infrastructure and service facilities while providing

adequate stakeholder consultation.

ISEPP relates primarily to public infrastructure projects developed for or on behalf of public

authorities. In accordance with Clause 106 (2), development for the purpose of sewage

treatment plants may be carried out without consent on land in a prescribed zone in the

prescribed circumstances. Clause 106 (3B) states that development for the purpose of sewage

reticulation systems may be carried out without consent on any land in the prescribed

circumstances.

Prescribed circumstances (refer Clause 106 (1)) occur if the development:

(a) is carried out by or on behalf of a public authority, or

(b) consists of the construction or operation of water industry infrastructure and, under the

Water Industry Competition Act 2006, a network operator’s licence is required before the

development may be carried out.

A prescribed zone (refer Clause 105) is defined as any of the following zones:

(a) RU1 Primary Production

(b) RU2 Rural Landscape

(c) RU4 Primary Production Small Lots

(d) IN1 General Industrial

(e) IN3 Heavy Industrial

(f) SP1 Special Activities

(g) SP2 Infrastructure

If the proposal meets the above, it would be considered development permissible without

consent and a Review of Environmental Factors (REF) would be prepared for determination by

Council.

If the proposal does not meet the requirements for prescribed circumstances, Clause 106 (2A)

and (3B) state that a sewage treatment plant or sewage reticulation system may be carried out

with consent on any land. However in the case of an STP (Clause 2(A)), the development must

be within a prescribed zone.


Clause 8 (2) of ISEPP states that “if there is an inconsistency between a provision of this Policy

and any of the following provisions of another environmental planning instrument, the provision

of the other instrument prevails to the extent of the inconsistency:

(a) clauses 10, 11 and 19 of State Environmental Planning Policy (Coastal Management) 2018’.

This is discussed further below.

State Environmental Planning Policy (Coastal Management) 2018

State Environmental Planning Policy (Coastal Management) 2018 (Coastal Management SEPP)

aims to promote an integrated and co-ordinated approach to land use planning in the coastal

zone in a manner consistent with the objectives of the Coastal Management Act 2016.

The proposal contains several areas that are mapped under the Coastal SEPP. Key areas when

determining the approval pathway for the project are those mapped as coastal wetlands and

littoral rainforest (see Figure 7 in Appendix A). Any development within these areas may be

carried out only with development consent (pursuant to Clause 10 of the Coastal SEPP). The

application for consent must be accompanied by an environmental impact statement (EIS).

As discussed above, in accordance with Clause 8(2) of ISEPP, the Coastal Management SEPP

prevails over ISEPP. Therefore any of the options that intersect the mapping shown in Figure 7,

will require development consent and an EIS.

For local development (i.e. not regional or state significant, discussed below), the applicant must

seek the Secretary’s environmental assessment requirements (SEARs) for the EIS from the

Department of Planning and Environment (DPE). The EIS would then be prepared to address

the SEARs and the relevant requirements of the EP&A Act and Regulation. The EIS is

submitted to Council for determination.

State Environmental Planning Policy (State and Regional Development) 2011

State Environmental Planning Policy (State and Regional Development) 2011 (SEPP SRD)

defines development that is considered state significant development (SSD), state significant

infrastructure (SSI), critical SSI and regionally significant development (RSD).

A project meets the definition of SSD as per Clause 22 of Schedule 1 of SEPP SRD if:

a) handles more than 10,000 EP (equivalent population), or

(b) has a capital investment value of more than $30 million, or

(c) has a capital investment value of more than $10 million and is located in an environmentally

sensitive area of State significance.

An environmentally sensitive area of State significance includes land identified as ‘coastal

wetlands’ or ‘littoral rainforest’ under the Coastal Management SEPP.

For SSD, the applicant must also seek the SEARs for the EIS from the DPE. The EIS would

then be prepared to address the SEARs and the relevant requirements of the EP&A Act and

Regulation but is then submitted to the DPE for determination.

The proposal would not meet the definition of SSI or critical SSI.

RSD is defined under Schedule 7 of SEPP SRD. Council related development with a capital

investment value of over $5 million is defined as RSD. In this case the EIS is submitted to

Council for assessment but is determined by the Joint Regional Planning Panel (JRPP).

There may be an opportunity for the proposal to split approvals i.e. EIS and determination by

DPE for the transfer options and REF and determination by Council for the STP option. This

approach should be confirmed with DPE.


The application of the above to each of the options assessed is summarised in Table 6-1.

Table 6-1 Summary of Approval Considerations

Option Coastal SEPP mapping – wetland and rainforest

CIV estimate* Prescribed circumstances#

Approval pathway

Option 1A Yes - Consent required

RSD

Option 1B Yes - Consent required

SSD

Option 1C Yes - Consent required

RSD

Option 2A No Yes Consent not required

Option 1 No No

(zoned RE1)

Consent required

RSD

Option 2+ No Yes

(zoned RU2)

Consent not required

Option 1A + 1 Yes - Consent required

SSD

Option 1B + 1 Yes - Consent required

SSD

Option 1C + 1 Yes - Consent required

SSD

Option 2A + 2 No Yes Consent not required

* Estimate only, see Section 7.2. Costs do not include low-pressure collection network costs

(common to all options), contingencies, preliminaries and engineering on-costs etc.

# Refer land use zones shown in Figure 10 in Appendix A.

+ We have assumed that offsite effluent disposal proposed for STP option 2 can be defined as

reticulation not treatment.

Review of Table 6-1 highlights the following:

Transfer options 1A, 1B and 1C all require development consent in accordance with

Clause 10 of the Coastal Management SEPP (EIS).

Transfer option 1B meets the definition of SSD, while option 1A and 1C currently fit the

definition of RSD (this may change if cost estimates are updated) as per Schedule 1 and

7 of SEPP SRD.

In accordance with Clause 106 (3B) of ISEPP, transfer option 2A is development

permissible without consent. A REF would be prepared in accordance with Part 5 of the

EP&A Act. Council would be the determining authority.

STP option 1 would require consent. It would also meet the definition of RSD (this may

change if cost estimates are updated) as per Schedule 7 of SEPP SRD. Sewage

treatment plants are permissible with consent in the RE1 zone under the Kempsey Local

Environmental Plan (LEP) 2013.

STP option 2 is development permissible without consent in accordance with Clause 106

(2) of ISEPP. A REF would be prepared in accordance with Part 5 of the EP&A Act.

Council would be the determining authority.


Combined transfer options 1B, 1A or 1C and STP Option 1 all require consent in

accordance with Clause 10 of the Coastal Management SEPP and would all meet the

definition of SSD.

Combined transfer option 2A and STP Option 2 is development permissible without

consent in accordance with Clause 106 (2) and (3B) of ISEPP. A REF would be prepared

in accordance with Part 5 of the EP&A Act. Council would be the determining authority.

6.1.2 Other Legislation Review

Legislation other than the EP&A Act (addressed above) that may apply to the project is

summarised in Table 6-2.

Table 6-2 Preliminary Legislation Review

Legislation Requirements and Comment

Commonwealth Legislation

Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act)

Under the EPBC Act a referral is required to the Australian Government for proposed ‘actions that have the potential to significantly impact on matters of national environmental significance or the environment of Commonwealth land.’

A search for matters of national environmental significance would need to be completed and potential impacts assessed. If impacts are considered likely to be significant, the project would need to be referred to the Commonwealth Minister for the Environment for a determination as to whether EPBC Act approval is required.

Native Title Act 1993 The Native Title Act 1993 recognises and protects native title and provides that native title cannot be extinguished contrary to the Act. Essentially, the Act covers actions affecting native title and the process for determining whether native title exists and compensation for actions affecting native title. It establishes the Native Title Registrar, the National Native Title Tribunal, the Register of Native Title Claims and the Register of Indigenous Land Use Agreements, and the National Native Title Register (NNTR).

A search of the NNTR did not identify any active or approved claims in the project area, however Council have indicated they are aware of an incomplete land claim on the proposed site of the Stuarts Point STP.

Furthermore, Aboriginal stakeholders have noted their support for a Stuarts Point STP.

NSW Legislation

Roads Act 1993 Section 138 of the Roads Act requires that a person must not carry out work in, on or over a public road or dig up or disturb the surface of a public road without the prior consent of the appropriate roads authority.

The project would require works within the road reserve and this approval would likely be required.

Fisheries Management Act 1994 (FM Act)

Under Part 7 of the FM Act, a permit is required for dredging and reclamation, obstruction of fish passage, harm to marine vegetation and use of electrical or explosive devices in a waterway. Dredging and reclamation, and harm to marine vegetation are likely. However as SSD, an approval is not required.

Threatened aquatic species, populations and communities are listed under the FM Act. This would need to be assessed for the project.



National Parks and Wildlife Act 1974 (NPW Act)

The NPW Act aims to conserve nature, objects, places or features (including biological diversity) of cultural value within the landscape. If an impact to an Aboriginal heritage object or site is likely from a proposal, a permit must be sought under Section 90. However as SSD, an approval is not required.

Approval must also be sought for any activity on national park estate under this Act. The closest protected area is the Fisherman Bend Nature Reserve (see Figure 8 in Appendix A). The project is unlikely to directly impact on the park.

Biodiversity Conservation Act 2016 (BC Act)

The BC Act outlines the factors to be considered when making an assessment of impact of a proposal on biodiversity. If a significant impact is deemed likely following this assessment, a Species Impact Statement or a Biodiversity Development Assessment Report may be required.

It is possible the project would impact on threatened species, populations and communities or their habitat and this would need to be assessed in the EIS.

Heritage Act 1977 The Heritage Act 1977 aims to ensure that the heritage of NSW is adequately identified and conserved. Under Section 57, a permit must be obtained for works, which have the potential to interfere with a heritage item or place, which is either listed on the State Heritage Register or the subject of an interim heritage order.

There are no listed heritage items in or near the project.

Water Management Act 2000 (WM Act)

The WM Act aims to ensure that water resources are conserved and properly managed for sustainable use benefitting both present and future generations. It also provides formal protection and enhancement of the environmental quality of waterways and in-stream uses as providing protection of catchment conditions.

Water use approvals are required under the WM Act for the taking of water unless an exemption under the Regulation applies. However as SSD, an approval is not required.

The WM Act also requires controlled activity approvals to carry out specified controlled activities on or under waterfront land. The proposal would be undertaken on waterfront land (within 40 metres of the bed of a river or estuary) and as such comprises a controlled activity under the WM Act. Councils are exempt from acquiring activity approvals under the WM Act.

Protection of the Environment Operations Act 1999 (POEO Act)

Under Section 48 of the Act, an environmental protection licence relating to air, water and noise pollution or waste management is required for scheduled activities as listed under Schedule 1 of the Act.

It is possible the project meets the definition of a scheduled activity under Schedule 1 if the project has a processing capacity that exceeds:

(a) 2,500 persons equivalent, as determined in accordance with guidelines established by an EPA Gazettal notice, or

(b) 750 kilolitres per day,

If the above applies, an environmental protection licence under the POEO Act would be required.



Biosecurity Act 2015 This Act provides for the declaration of priority weeds and biosecurity zones by the Minister for Primary Industries. The Act also lists plant pests and diseases that are prohibited and notifiable in NSW. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable.

Any priority weeds identified under the Act must be treated as prescribed if encountered.

Waste Avoidance and Resource Recovery Act 2000

This Act provides a framework to identify and implement the most efficient use of resources in order to reduce the potential for environmental harm arising from the generation of waste.

The construction contractor would be required to conform to the provisions of the Act in relation to waste management by adopting the resource management hierarchy principals (in order of priority) of avoidance, resource recovery and disposal.

Crown Land Management Act 2016

The project would require works on Crown land and Crown waterways. The work proposed would require a licence under this Act prior to the commencement of works. As owner of the land, consent to submit the EIS would also be required from the Crown.

Marine Safety Act 1998 The Marine Safety Act 1998 ensures the safe operation of vessels in ports and other waterways. Aquatic licences are issued under the Marine Safety Act 1998 for any activity (whether or not vessels or equipment are involved) that’s conducted, organised or promoted in, or on, any navigable waters that restricts the availability of those waters for normal use by the public. The project may require a licence for any works on the waterway.

Coastal Management Act 2016 (CM Act)

The CM Act establishes the framework and overarching objects for coastal management in New South Wales.

The purpose of the CM Act is to manage the use and development of the coastal environment in an ecologically sustainable way, for the social, cultural and economic well-being of the people of NSW. The CM Act establishes management objectives specific to four management areas mapped under the Coastal Management SEPP, reflecting their different values to coastal communities. Works within the coastal zone (which applies to most of the proposal site) must be considered against the requirements of the CM Act, where relevant.


In accordance with Section 4.41 of the EP&A Act, the following approvals (relevant to the

project) do not apply to SSD:

A permit under section 201, 205 or 219 of the Fisheries Management Act 1994

An Aboriginal heritage impact permit under section 90 of the National Parks and Wildlife

Act 1974

A water use approval under section 89, a water management work approval under

section 90 or an activity approval (other than an aquifer interference approval) under

section 91 of the Water Management Act 2000.

6.1.3 Reassessment of Environmental and Planning Review

The assessment included in the preceding sections, should be reviewed once more detailed

designs for the proposal are developed. The assessment constitutes a preliminary review only

based on conceptual design, location and constraints information only.


7. Comparison of options

7.1 Multi Criteria assessment

The sewage treatment options and transfer pipeline options developed in Chapters 3 and 4

were compared using a high-level, multi criteria analysis.

The evaluation criteria selected comprise:

Constructability

Maintainability

Environmental/Social Issues

Financial

The following weighting was assigned to each criteria following a workshop between GHD and

KSC.

Criteria Weighting

Constructability 25%

Maintainability 25%

Environmental Risk/Social Issues 25%

Financial Impact 25%

Total 100%

For each of these criteria, a score between 0 – 5 was assigned based on the following rating

system.


Table 7-1 MCA Ranking Table

Points Range

Impact Rating Constructability Maintainability Environmental/Social

0 Unacceptable Service (Eliminate from consideration as viable option)

Construction requires materials and expertise that are not available.

Unacceptable community impacts.

Unacceptable construction conditions from a safety or constructability viewpoint.

Facility will increase the operation and maintenance workload at considerable cost.

Frequent maintenance intervention will be required AND/OR difficult and unfamiliar maintenance requirements.

High risk of license noncompliance without rapid response maintenance attention.

Safety Risks are high.

Construction will provide the most interruption to the community and the environment.

1 Very High (Least Preferred - NOT desirable)

Construction using difficult techniques involves high safety risks and long lead times for supply of materials or equipment.

Contains high risk of delays.

Constructability severely constrained by prevailing conditions.

Facility will require significant increased maintenance workload and cost with new facility.

Frequent maintenance intervention will be required AND/OR difficult and unfamiliar maintenance requirements.

Safety risks are high.

Construction will provide a very high impact to the environment and interruption to the community.

2 High (Requires significant management)

Construction using difficult techniques involves significant safety risks has some community impacts that would be difficult to manage.

Facility will require significant increased maintenance workload and cost with new facility.

New maintenance systems may be required.

Construction will provide a high impact to the environment and interruption to the community.

3 Moderate (Negotiable)

Construction using techniques that involves new technology AND/OR has significant community impacts that can be managed.

Facility will provide no change to operability workload.

New or less widely used technical solution that will work with appropriate construction and management in service.

Requires more operational intervention.

Construction will provide a moderate impact to the environment and interruption to the community.

4 Normal (Acceptable)

Construction using well tested and familiar construction and familiar construction techniques.

Facility will provide some improved operability through reduced or enhanced maintenance workload and cost and negligible operational risk.

Construction will provide an acceptable level of interruption to the community and the environment.


Points Range

Impact Rating Constructability Maintainability Environmental/Social

5 Low (Most Preferred)

Construction using well tested and familiar construction techniques.

Facility will provide extensive improved operability through reduced maintenance workload and cost and negligible operational risk.

Facility will provide improved environment when maintenance is required.

Construction will provide the least interruption to the community and the environment.

*Financial scoring was calculated based on a relative score to the minimum cost


7.1.1 Sewage Treatment MCA

Evaluation Criteria Weighting Option 1

Augment STP on South West Rocks Option 2

Construct New STP on Stuarts Point Scoring: 1 - least preferred to 5 - most preferred

%

Criteria: Meets objectives/drivers Meets all objectives Meets all objectives

Criteria: Constructability Moderate

(Negotiable) Normal

(Acceptable)

To ensure that the existing South West Rocks treatment plant is capable of handling the additional Stuarts Point load requires a planning study to review the hydraulic and biological capacity of the plant. This process also requires a review of the licensing requirements and additional investigation to construct suitable effluent disposal systems

This is the construction of a new sewage treatment plant in Stuarts Point. The risk involved in construction and capacity are low. However, obtaining approval and new licensing may be challenging.

Score 3 4

Weighted score 25% 0.75 1

Criteria: Maintainability Normal

(Acceptable) Low

(Most Preferred)

Since the works involve augmenting an existing plant, the existing maintenance practices shall prevail. As such, maintainability is moderate since the plant includes a majority of the original assets which may not be contribute to short-medium term defects.

The plant is expected to be in suitable working order following commissioning.

Score 4 5

Weighted score 25% 1 1.25


Evaluation Criteria Weighting Option 1

Augment STP on South West Rocks Option 2

Construct New STP on Stuarts Point Scoring: 1 - least preferred to 5 - most preferred

%

Criteria: Environmental/Social Issues

Moderate

(Negotiable) High

(Requires significant management)

Since the plant requires augmentation, there may be an increase in outfall and a potential trigger for a new license.

The construction of a new wastewater treatment plant adjacent to a major roadway poses significant environmental and social risks to be managed by Council. New environmental approval will be required for a new contaminated site. Proximity to residents may have negative impacts due to odour without sufficient mitigation measures. However, a Stuarts Point STP may provide re-usable effluent for avocado farm irrigation.

Score 3 2

Weighted score 25% 0.75 0.5

Financial

Order of Capital Cost (excl GST)

Criteria: Lowest Capital Cost favoured.

Score 4.84 5.00

Weighted score 25% 1.21 1.25

Scores – (Weighted score) 100% 3.71 4.00

Highest is preferred


7.1.2 Sewage Transfer Route MCA

Evaluation Criteria Weighting Option 1A

Northern Crossing of Macleay River to Quarry Street

Option 1B Northern Crossing of Macleay River to New Entrance Road

Option 1C Southern Crossing of

Macleay River

Option 2A Rising Main Up to New

Stuarts Point STP

Scoring: 1 - least preferred to 5 - most

preferred %

Criteria: Meets objectives/drivers

Meets all objectives Meets all objectives Meets all objectives Meets all objectives

Criteria: Constructability

Moderate

(Negotiable)

High (Requires significant

management)

Very High (Least Preferred - NOT

desirable)

Normal (Acceptable)

Heritage consultants and searches have found that Shark Island Crossing may be inappropriate due to cultural significance of the area. The risk of HDD across Macleay river is similar to Option 1, however, the staged and shorter HDD crossings may improve constructability and reduce the associated risks.

Heritage consultants and searches have found that Shark Island Crossing may be inappropriate due to cultural significance of the area. The risk of HDD across Macleay river is similar to Option 1, however, the staged and shorter HDD crossings may improve constructability and reduce the associated risks. The implications of odour management and high point management is present along Keith Andrews Drive.

Heritage consultants have informed the corridor between Fisherman's Reach and Lindsay's Trail contain repatriated aboriginal skeletal remains. The

Kempsey Shire Council...2018/12/18 · GHD | Report for Kempsey Shire Council - Stuarts Point...

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