Notice of Meeting

Floodplain Management Advisory Committee Meeting

A Floodplain Management Advisory Committee Meeting of Byron Shire Council will be held as follows:

 

Venue

Conference Room, Station Street, Mullumbimby

Date

Tuesday, 16 May 2023

Time

11.30am

 

 

Phil Holloway

Director Infrastructure Services

I2023/716

                                                                                                                             Distributed 09/05/23

 

 

 

 


CONFLICT OF INTERESTS

What is a “Conflict of Interests” - A conflict of interests can be of two types:

Pecuniary - an interest that a person has in a matter because of a reasonable likelihood or expectation of appreciable financial gain or loss to the person or another person with whom the person is associated.

Non-pecuniary – a private or personal interest that a Council official has that does not amount to a pecuniary interest as defined in the Code of Conduct for Councillors (eg. A friendship, membership of an association, society or trade union or involvement or interest in an activity and may include an interest of a financial nature).

Remoteness – a person does not have a pecuniary interest in a matter if the interest is so remote or insignificant that it could not reasonably be regarded as likely to influence any decision the person might make in relation to a matter or if the interest is of a kind specified in the Code of Conduct for Councillors.

Who has a Pecuniary Interest? - a person has a pecuniary interest in a matter if the pecuniary interest is the interest of the person, or another person with whom the person is associated (see below).

Relatives, Partners - a person is taken to have a pecuniary interest in a matter if:

·                The person’s spouse or de facto partner or a relative of the person has a pecuniary interest in the matter, or

·                The person, or a nominee, partners or employer of the person, is a member of a company or other body that has a pecuniary interest in the matter.

N.B. “Relative”, in relation to a person means any of the following:

(a)  the parent, grandparent, brother, sister, uncle, aunt, nephew, niece, lineal descends or adopted child of the person or of the person’s spouse;

(b)  the spouse or de facto partners of the person or of a person referred to in paragraph (a)

No Interest in the Matter - however, a person is not taken to have a pecuniary interest in a matter:

·                If the person is unaware of the relevant pecuniary interest of the spouse, de facto partner, relative or company or other body, or

·                Just because the person is a member of, or is employed by, the Council.

·                Just because the person is a member of, or a delegate of the Council to, a company or other body that has a pecuniary interest in the matter provided that the person has no beneficial interest in any shares of the company or body.

Disclosure and participation in meetings

·                A Councillor or a member of a Council Committee who has a pecuniary interest in any matter with which the Council is concerned and who is present at a meeting of the Council or Committee at which the matter is being considered must disclose the nature of the interest to the meeting as soon as practicable.

·                The Councillor or member must not be present at, or in sight of, the meeting of the Council or Committee:

(a)     at any time during which the matter is being considered or discussed by the Council or Committee, or

(b)     at any time during which the Council or Committee is voting on any question in relation to the matter.

No Knowledge - a person does not breach this Clause if the person did not know and could not reasonably be expected to have known that the matter under consideration at the meeting was a matter in which he or she had a pecuniary interest.

Non-pecuniary Interests - Must be disclosed in meetings.

There are a broad range of options available for managing conflicts & the option chosen will depend on an assessment of the circumstances of the matter, the nature of the interest and the significance of the issue being dealt with.  Non-pecuniary conflicts of interests must be dealt with in at least one of the following ways:

·                It may be appropriate that no action be taken where the potential for conflict is minimal.  However, Councillors should consider providing an explanation of why they consider a conflict does not exist.

·                Limit involvement if practical (eg. Participate in discussion but not in decision making or vice-versa).  Care needs to be taken when exercising this option.

·                Remove the source of the conflict (eg. Relinquishing or divesting the personal interest that creates the conflict)

·                Have no involvement by absenting yourself from and not taking part in any debate or voting on the issue as of the provisions in the Code of Conduct (particularly if you have a significant non-pecuniary interest)

Committee members are reminded that they should declare and manage all conflicts of interest in respect of any matter on this Agenda, in accordance with the Code of Conduct.

RECORDING OF VOTING ON PLANNING MATTERS

Clause 375A of the Local Government Act 1993 – Recording of voting on planning matters

(1)  In this section, planning decision means a decision made in the exercise of a function of a council under the Environmental Planning and Assessment Act 1979:

(a)  including a decision relating to a development application, an environmental planning instrument, a development control plan or a development contribution plan under that Act, but

(b)  not including the making of an order under that Act.

(2)  The general manager is required to keep a register containing, for each planning decision made at a meeting of the council or a council committee, the names of the councillors who supported the decision and the names of any councillors who opposed (or are taken to have opposed) the decision.

(3)  For the purpose of maintaining the register, a division is required to be called whenever a motion for a planning decision is put at a meeting of the council or a council committee.

(4)  Each decision recorded in the register is to be described in the register or identified in a manner that enables the description to be obtained from another publicly available document and is to include the information required by the regulations.

(5)  This section extends to a meeting that is closed to the public.

OATH AND AFFIRMATION FOR COUNCILLORS

Councillors are reminded of the oath of office or affirmation of office made at or before their first meeting of the council in accordance with Clause 233A of the Local Government Act 1993. This includes undertaking the duties of the office of councillor in the best interests of the people of Byron Shire and the Byron Shire Council and faithfully and impartially carrying out the functions, powers, authorities and discretions vested under the Act or any other Act to the best of one’s ability and judgment.


BYRON SHIRE COUNCIL

BUSINESS OF MEETING

 

1.    Apologies

2.    Declarations of Interest – Pecuniary and Non-Pecuniary

3.    Adoption of Minutes from Previous Meetings

3.1       Adoption of Minutes from Previous Meeting.............................................................. 6

 

4.    Staff Reports

Infrastructure Services

4.1       Federation Bridge Debris Contol Measures............................................................ 15

4.2       North Byron Sky Pump Proposal............................................................................... 74

4.3       Byron Drainage Upgrade Strategy............................................................................ 81

4.4       Byron Shire Post 2022 Flood Analysis Update....................................................... 89     

 

 


BYRON SHIRE COUNCIL

Adoption of Minutes from Previous Meetings                                                   3.1

Adoption of Minutes from Previous Meetings

 

Report No. 3.1       Adoption of Minutes from Previous Meeting 

Directorate:                         Infrastructure Services

Report Author:                   Dominika Tomanek, Executive Assistant Infrastructure Services

File No:                                 I2023/678

 

  

 

RECOMMENDATION:

That the minutes of the Floodplain Management Advisory Committee Meeting held on 14 February 2023 be confirmed.

 

 

Attachments:

 

1        Minutes 14/02/2023 Floodplain Management Advisory Committee, I2023/168 , page 9  

 


 

Report

The attachment to this report provides the minutes of the Floodplain Management Advisory Committee Meeting of 14 February 2023 . 

 

Report to Council

The minutes were reported to Council on 23 March 2023.

Comments

In accordance with the Committee Recommendations, Council resolved the following:

23-091

Resolved that Council adopts the following Committee Recommendations:

Report No. 4.1 Byron Shire Council-Strategic Fill Policy

Committee Recommendation 4.1.1

That the Floodplain Management Advisory Committee advises Council:

1.      That committee members will meet between quarterly meetings to consider;

          a)        changes to strengthen Chapters B14 and C2 of the 2014 Byron Shire Council Development Control Plan in relation to Fill on Floodplains;

          b)        the value of a broader Policy that goes beyond what the DCP can achieve in limiting Fill on Floodplains;

          and that the support of appropriate planning staff would be greatly appreciated in such considerations.

2.      To resolve that the 2014 Byron Shire Council Development Control Plan should be updated as a priority each and every time a Floodplain Risk Management Study is created or updated within the Shire or across our Shire boundaries (eg the Tweed – Byron Coastal Creeks Flood Study of 2010).  

3.      To update the 2020 North Byron Floodplain Risk Management Study as soon as possible to reflect the February 2022 flood event. 

4.      To update the 2020 North Byron Floodplain Risk Management Plan as soon as possible to reflect changes caused by the February 2022 flood event.

23-092

Resolved that Council adopts the following Committee Recommendation:

Report No. 4.2 Modelling of Various Flow Scenarios at South Golden Beach

Committee Recommendation 4.2.1

That Council includes in the information it will disseminate under AGRN1012 -Local Government Recovery Grant Program results of a basic review of extracting water from the floodplain north of New Brighton.

23-093

Resolved that Council adopts the following Committee Recommendations:

Report No. 4.3 Hydrology Inputs to the North Byron 2020 Flood Model

Committee Recommendation 4.3.1

That Council:

1.      Notes that all catchment inflows are included in the Council adopted North Byron Flood Risk Management Study; and

2.     Includes in the information it will disseminate under Local Government AGRN1012 - Recovery Grant Program results discussed by WMA in Attachment 1 of this report.

23-094

Resolved that Council adopts the following Committee Recommendations:

Report No. 4.4 Byron Shire Post 2022 Flood Analysis Update

Committee Recommendation 4.4.1

That Council:

1.      Notes the report to the Floodplain Management Advisory Committee; and

2.      Circulates the 2022 Flood Analysis Reports as soon as they are available and then call an extraordinary Committee meeting to consider the reports.         

 

 


BYRON SHIRE COUNCIL

Adoption of Minutes from Previous Meetings                                         3.1 - Attachment 1






 


BYRON SHIRE COUNCIL

Staff Reports - Infrastructure Services                                                            4.1

Staff Reports - Infrastructure Services

 

Report No. 4.1       Federation Bridge Debris Contol Measures

Directorate:                         Infrastructure Services

Report Author:                   Scott Moffett, Drainage & Flood Engineer, IS - Works - Infrastructure Planning

File No:                                 I2023/651

Summary:

Byron Shire Council (BSC) has commissioned Arcadis to undertake an assessment of possible control measures (structural or otherwise) to resolve the issues associated with accumulation of debris under Federation Bridge.

This report discusses the outcomes of the options investigation and shows that option 3 is the preferred option.

Council staff and Arcadis will present the project to the Floodplain Advisory Committee.

  

 

 

RECOMMENDATION:

That the Floodplain Management Advisory Committee notes the attached report, the presentation and approves the preferred option 3 in accordance with the multi criteria analysis detailed within Attachment 1 (E2023/41906) Federation Bridge Debris Control Options Assessment

Attachments:

 

1        0005-30156205-AAS-01- Federation Bridge Debris Control - Stage 1 Options Assessment - SENT 27th April 2023, E2023/41906 , page 18  

 


 

Report

Byron Shire Council (BSC) have commissioned Arcadis to undertake an assessment of possible control measures (structural or otherwise) to resolve the issues associated with accumulation of debris under Federation Bridge.

Stage 1 of the project provides the options assessment and recommended option to then be carried forward into Stages 2 and 3, design and implementation.

Federation Bridge is a multi-span bridge on Murwillumbah Road that crosses Brunswick River in Mullumbimby, NSW and connects the eastern and western sides of Mullumbimby township and Billinudgel township to the north.

The requirement for debris controls measures for Federation Bridge to be investigated, were based on one of the recommended outcomes given in the North Byron Floodplain Risk Management Plan (FRMP) (WMA, 2020a).  Due to the substantial community support for debris control measures, implementing debris control measures for Federation Bridge was adopted as a high priority in the North Byron FRMP.

The first stage was to undertake the options assessment, via a Multi-Criteria Analysis (MCA) process to determine the most viable debris control measure’s available in order to minimise the debris accumulation under Federation Bridge, and to reduce the impact of debris especially during flood events.

Attachment 1 provides an overview and the outcomes of the options assessment investigation. The report nominates option 3 as the preferred option.

Key issues

Structural options versus non-structural options have been assessed.  All structural options came with downsides therefore a non-structural options has been recommended within the report.

Options

1)   Structural: Debris fins

2)   Structural: Debris sweeper

3)   Camphor Laurel management and bush regeneration (preferred option)

4)   Targeted Flood Event Management

5)   Periodic Removal and habitat creation

6)   Business as Usual - do nothing

Next steps

·    Attachment 1 provides the outcome of the options assessment. Option 3 is shown to be the preferred option based on the MCA.

·    Explore potential fundings options and develop a business case, which outlines flood mitigation benefits as well as wider environmental and community benefits.

Legal/Statutory/Policy Considerations

The Floodplain Development Manual supports the policy and guides councils through the floodplain risk management process.  The manual helps councils develop and implement local floodplain risk management plans and outlines the technical assistance provided by the NSW Government.

The manual details the roles and responsibilities of various NSW agencies and includes information on:

·      the preparation of flood studies, floodplain risk management studies and plans

·      floodplain risk management options

·      flood planning levels and areas

·      hydraulic and hazard categorisation

·      emergency response planning.

 

The manual was gazetted in 2005 as the manual relating to the development of flood-liable land for the purposes of section 733 of the Local Government Act 1993.

Financial Considerations

Refer to attached report. Further funding will be required for the construction or on ground works stage.

Consultation and Engagement

Key stakeholder consultation was undertaken as part of this project.  This included all State and Federal agencies including the Environmental Protection Agency (EPA), Transport for NSW, Martine Services, Fisheries in additional to Councils bush regeneration team.

 


BYRON SHIRE COUNCIL

Staff Reports - Infrastructure Services                                                 4.1 - Attachment 1

























































BYRON SHIRE COUNCIL

Staff Reports - Infrastructure Services                                                            4.2

Report No. 4.2       North Byron Sky Pump Proposal

Directorate:                         Infrastructure Services

Report Author:                   Scott Moffett, Drainage & Flood Engineer, IS - Works - Infrastructure Planning

File No:                                 I2023/652

Summary:

On 24th March 2023 Council resolved the following committee recommendation (23-092)

Council adopts the following Committee Recommendation:

·    Report No. 4.2         Modelling of Various Flow Scenarios at South Golden Beach File No: I2023/89

Committee Recommendation 4.2.1

That Council includes in the information it will disseminate under AGRN1012 -Local Government Recovery Grant Program results of a basic review of extracting water from the floodplain north of New Brighton.

This report addresses this resolution and other actions requested by the committee.

  

 

 

RECOMMENDATION:

That the Floodplain Management Advisory Committee recommends Council support the proposed scope for the North Byron Sky Pumps Proposal

 

 

 


 

                               

Report

On 24th March 2023 Council resolved the following committee recommendation (23-092)

Council adopts the following Committee Recommendation:

·    Report No. 4.2         Modelling of Various Flow Scenarios at South Golden Beach File No: I2023/89

Committee Recommendation 4.2.1

That Council includes in the information it will disseminate under AGRN1012 -Local Government Recovery Grant Program results of a basic review of extracting water from the floodplain north of New Brighton.

In order to achieve this action it is proposed to model a ‘Sky Pumps’ scenario in the North Byron Flood Model.  The following is the proposed scope.

Model two versions of the 100 year flood to understand the pump volumes, rates and size that would be required to prevent a prescribed amount of flooding for each event scenario

Develop and run the following scenarios in the North Byron Flood Model

·    Flood Event Scenario A - A ocean dominated 100 year flood with a 100 year tail water of 2.6m AHD and 100 year rainfall.

·    Flood Event Scenario B - A 100 year flood with 100 year rainfall flood and a 20 year climate change tailwater boundary condition.

Each Flood Event Scenario above will assess three ‘Sky Pumps’ operating together. The location of the pumps is provided in the below images. The pumps will run together in three different set ups.

Set Up One – Commence pumping when water levels reach 200mm below the 100 year flood peak for the location. The pumps are to be sized to prevent any water level increase above the turn on level for the duration on the flood.

Set Up Two - Commence pumping when water levels reach 400mm below the 100 year flood peak for the location.  The pumps are to be sized to prevent any water level increase above the turn on level for the duration on the flood.

Set Up Three - Commence pumping when water levels reach 600mm below the 100 year flood peak for the location.  The pumps are to be sized to prevent any water level increase above the turn on level for the duration on the flood.

The term ‘Sky Pump’ has been used because for assessment purposes the discharge water from the pumps will disappear into the aether.  The purpose of this assessment is to understand the extraction volumes and rates required to achieve three different flood mitigation outcomes. Disposal of this water will be investigated further if required following this initial investigation.

Typical costs to achieve the desired mitigation volumes and rates will also be discussed.

The three ‘Sky Pump’ locations is shown in the below images.  They were selected on the basis that they are:

·    Low elevation (around 1.2m/ 1.3 AHD), hence will be an area that will be inundated early in a flood event

·    Still have semi-intact remnant drainage channels that will carry floodwater from overflow from Marshalls Creek or Billinudgel Nature Reserve

Locations are:

1.      North of sports field at New Brighton (153.5491, -28.5037) – this land is privately owned.

2.      South of levee at SGB (154.5499, -28.4984) – this land is a mix of Crown and National Parks land.

3.      Remnant dredged channel from 1970s in Billinudgel Nature Reserve (intersects remnant channel which carried water to Helen Street outlet) (153.5506, -28.4856) - this land is privately owned, however, some National Parks land is to the south.


 

Location One:


 

Location two:


 

Location 3:

 

Key issues

The proposal does simplify a complicated flood mitigation scenario; therefore, the assessment does have its limitations. However, the proposal will provide a simple understanding of potential extraction volumes and rates required to achieve three different flood mitigation outcomes. This will help with community understanding what is needed to achieve these scenarios.

Disposal of pumped water will not be considered; this would need to be understood better as it could make pumping a very costly or difficult mitigation solution.

Next steps

The proposed scope will be added to an existing Request For Quote for a Third Party Peer review and community consultation process on Council previous flood mitigation investigations in the North of the shire.

Recent Resolutions

·        23-092

Legal/Statutory/Policy Considerations

The Floodplain Development Manual supports the policy and guides councils through the floodplain risk management process. The manual helps councils develop and implement local floodplain risk management plans and outlines the technical assistance provided by the NSW Government.

The manual details the roles and responsibilities of various NSW agencies and includes information on:

·      the preparation of flood studies, floodplain risk management studies and plans

·      floodplain risk management options

·      flood planning levels and areas

·      hydraulic and hazard categorisation

·      emergency response planning.

 

The manual was gazetted in 2005 as the manual relating to the development of flood-liable land for the purposes of section 733 of the Local Government Act 1993.

Financial Considerations

This assessment will be funded under an existing grant funded catchment assessment.

Consultation and Engagement

Staff met with Robert Crossley, his group and Cr Lyon and Cr Hunter to discuss the proposed scope on Friday 28th April 2023.

 


BYRON SHIRE COUNCIL

Staff Reports - Infrastructure Services                                                            4.3

Report No. 4.3       Byron Drainage Upgrade Strategy

Directorate:                         Infrastructure Services

Report Author:                   Scott Moffett, Drainage & Flood Engineer, IS - Works - Infrastructure Planning

File No:                                 I2023/653

Summary:

The Byron Bay Drainage Upgrade Strategy is a Floodplain Management Measure in the Council adopted Belongil Creek Floodplain Risk Management Plan (2015).

The project is funded by the "Preparing Australian Communities" grant to develop the drainage strategy through Concept Design to Detailed Design.  Essentially developing a construction ready project.

This report provides a status update for the project.

 

  

 

 

RECOMMENDATION:

That the Floodplain Management Advisory Committee notes the update on the Byron Drainage Upgrade Strategy.

 

 


 

Report

The Byron Bay Drainage Upgrade Strategy is a Floodplain Management Measure in the Council adopted Belongil Creek Floodplain Risk Management Plan (2015).

The project is funded by the "Preparing Australian Communities" grant to develop the drainage strategy through Concept Design to Detailed Design.  Essentially developing a construction ready project.

The project has three proposed stages that make up the Byron Bay Drainage Upgrades. They can be delivered separately or together as follows:

·    Town Centre – Includes upgrades of the gravity drainage system within the town centre.

 

·    Shirley Street – Includes construction of the towns main pump station, a levee protecting the properties of the Shirley Street area from regional flooding and installation of flood pumps to cater for local drainage within the leveed area.

 

·    Cowper Street – Includes construction of a flood storage basin (Sandhills wetland) and upgrades to Cowper Street pipe outlet to Clarkes Beach. It also includes upgrades to cross drainage linkages between the Town Centre drainage, Cowper Street trunk drainage and possible flood pump. (The Sandhills Wetland can be delivered separately to the peripheral works).


 

There are 5 stages to deliver the detailed design of the drainage upgrades. The scope, status, dependencies and timeframes are summarised below:

Stage

Scope

Status

Dependencies

Program Timeframe

1

Strategy Review

Deliverable: Strategy Review report identifying issues with the current strategy and opportunities for optimisation in concept design

100%

Completed

Data Collection

14/4/2023

2

Detailed Survey of project area

80% Completed

 

30/4/2023

3

Concept Design of drainage upgrades

3a

Deliverable:

Draft Concept Design Drawings and report including flood modelling results and mapping

 

0%

Completion of survey

Sandhills Wetland Design

Byron Town Centre Masterplan

Clarks Beach Masterplan

25/8//2023

3b

Councillor Workshop

 

0%

Project review and general concept discussion

July 2023

3c

Deliverable:

Final Concept Design Drawings and report

0%

Consultation and information sessions with community

Draft Review and milestone Meeting with Technical Staff

11/9/2023

3d

Councillor Workshop

Report to Council General Meeting

Council Adoption of Concept Design

0%

Finalisation of Concept Design

Oct 2023

4

Environmental Assessment

Deliverable: Environmental studies, documentation and proposed approvals

0%

Identification of planning and regulatory pathways

(Note that timing will vary depending on specialist studies and need for EIS)

Finalise Concept Design

6/11/2023

5

Detailed Design

Deliverable: Construction drawings and specifications

0%

Council adoption of concept design

Pot holing to obtain utility depths

Environmental assessments and approvals

Electrical design and Essential Energy approvals (for pump stations)

26/3/2024

 


 

Key issues

The project scope overlaps with several other Council projects currently in progress and future masterplan projects. The drainage design upgrades will need to integrate with:

·    Sandhill’s Wetland – The detailed design of the Sandhills Wetland is complete, and EIS is currently being prepared.

 

·    Road Reconstruction projects - Including the underground drainage upgrades with road reconstruction / renewals is the best delivery method for Council.  It benefits the community by minimising disruption and avoids the costs associated with temporary works or reinstatement costs that would be necessary if drainage works were solely undertaken separately from road works.

 

·    The detailed design of the drainage upgrades will cover the necessary underground works required within the footprint of the Lawson Street and Byron Street Road reconstruction projects currently in Councils Capital Works program.

 

·    Consultant Engeny will work with the Place Manager for Byron Bay to develop a civil works scoping report for locations where the road and footpath shape will likely remain unchanged or changed.  The locations where change is warranted or planned would be the higher priority for full street upgrades.  This reporting will help guide full street upgrade designs that need to be prepared.

 

·    The Clarks Beach Master Plan is about to commence on Main Beach reserve and will need to include any upgrade works that will be required to the Cowper Street Outfall.  This is in the early stages and will be a point of discussion at steering committee meetings.

 

·    Byron Bay Town Centre Master Plan -The drainage strategy has also been requested / listed at the next Byron Town Centre Master Plan meeting for a presentation / briefing for early April to coincide with the completion of the Drainage Strategy Review Report.

The current contracted program from Engeny is currently delivering detail design in March 2024 ahead of the grant deadline of August 2024, however the following external dependencies present risks to delivery to the contracted program:

·    Council approval of the Concept Design may extend delivery deadlines if staff are not confident to proceed with detail design following the Councillor Workshop.

·    Consultation with affected property owners– The extent of properties directly affected by the proposed upgrades (such as properties adjoining levees and pump stations) will be identified at the concept design stage. Additional consultation with individual properties may be required depending on the design impacts.

·    Environmental Assessments and obtaining environmental approvals.  Whilst most of the drainage upgrades would be considered exempt development or development with without consent, it is possible that parts of the project could trigger third party referrals/ approvals (such as Crown Lands, Cultural Heritage assessments, Cape Byron Marine Park Authority etc). Further an EIS maybe required for some elements.

·    Essential Energy Certified Design for electrical upgrades. The currently adopted preferred drainage strategy for Byron Town drainage includes flood pumps. Pump installations may require electrical upgrades if electric pumps are adopted and existing power supplies cannot meet pump demands. The scope of electrical design will not be confirmed until concept design and the current program does not have allowance for obtaining Essential Energy approvals. This may delay delivery of parts of the detailed design of pumps, should they be included in upgrades

If any of the above project dependencies are encountered the Engeny contracted program maybe extended via an extension of time request. This will be reported via the PRG. Under the grant funding agreement, the project currently has a 5 month delivery buffer.

See Risk Register in: Pulse | Enterprise Risk Management

 

Next steps

·    Finalise survey

·    Continue with concept design

·    Commence regular meetings with the internal Project Reference Group

 


 

Strategic Considerations

Community Strategic Plan and Operational Plan

 

CSP Objective

CSP Strategy

DP Action

Code

OP Activity

5: Connected Infrastructure
We have connected infrastructure, transport, and facilities that are safe, accessible, and reliable

5.3: Invest in renewable energy and emerging technologies

5.3.1: Future needs - Plan for the infrastructure needs of the current and future population

5.3.1.1

Review and update 10 year Flood and Drainage Renewal and Upgrade program

Recent Resolutions

Not applicable

Legal/Statutory/Policy Considerations

The Floodplain Development Manual supports the policy and guides councils through the floodplain risk management process. The manual helps councils develop and implement local floodplain risk management plans and outlines the technical assistance provided by the NSW Government.

The manual details the roles and responsibilities of various NSW agencies and includes information on:

·      the preparation of flood studies, floodplain risk management studies and plans

·      floodplain risk management options

·      flood planning levels and areas

·      hydraulic and hazard categorisation

·      emergency response planning.

 

The manual was gazetted in 2005 as the manual relating to the development of flood-liable land for the purposes of section 733 of the Local Government Act 1993.


 

Financial Considerations

Budget – $1.28M

To date, Council has committed $315K which covers the Engineering design and survey up to completion of concept design.

Detailed Design is a provisional item in the contract for Engineering Design and will be subject to final pricing at the completion and adoption of concept design when the scope can be confirmed.  Environmental planning assessments are excluded from the Engeny’s engineering design scope and is subject to a separate engagement. Preparation of RFQ documentation will be undertaken in April with appointment of a planning consultant planned for early May 2023.

Project is currently projected to be delivered under budget.

Should Council be successful in securing funding for the construction of the drainage upgrades, Council should aim to not commence any works on ground until Winter 2024 at the earliest. Accelerating the detailed design carries risks and tendering should be carried out on a finalised holistic design.

Consultation and Engagement

A communication plan is currently being prepared with Council’s Comms team and will be the first point of discussion at the first internal Project Reference Group meeting and Floodplain Management Advisory Committee

 


BYRON SHIRE COUNCIL

Staff Reports - Infrastructure Services                                                            4.4

Report No. 4.4       Byron Shire Post 2022 Flood Analysis Update

Directorate:                         Infrastructure Services

Report Author:                   Scott Moffett, Drainage & Flood Engineer, IS - Works - Infrastructure Planning

File No:                                 I2023/654

Summary:

Following the recent flooding and rainfall events in 2022, Council has been working closely with State Emergency Services (SES), the Department of Planning & Environment (DPE) and flooding consultants to undertake a post event data collection and summary report.

This report provides a summary of actions and ongoing activities for discussion by the Floodplain Management Advisory Committee (FMAC).

Draft reports have been received by DPE and are currently undergoing quality assurance and technical review.

  

 

 

RECOMMENDATION:

That the Floodplain Management Advisory Committee recommends:

Council notes the report, the update by DPE and the Floodplain Management Advisory Committee minutes.

 


 

Report

Following the recent flooding and rainfall events in 2022, Council has been working closely with State Emergency Services (SES), the Department of Planning & Environment (DPE) along with flooding consultants to undertake a post event/s data collection and summary report.

Council initiated the first phase internal post event survey protocols immediately following the recent events.  Council’s Flood and Drainage Engineer was contacted by SES to collaborate in obtaining post event survey marks.

SES contracted Public Works Advisory (PWA) to provide survey resourcing across the Byron Shire.  DPE then became involved to oversee the data collection.  Council’s Flood and Drainage Engineer worked closely with SES, DPE and PWA to isolate the areas of interest with a focus on the main urbanised areas of the shire.

Post event survey has now been completed, including an SES, DPE and PWA, along with Council undertaking quality assurance checks.  This data is now available for use by Council.  Survey has covered the Brunswick River, Belongil, Tallow Creek catchments and Bangalow.

Council also initiated the second phase of post event survey protocols.  This involved releasing media alerts to all shire residents to ask for assistance with collection of additional private property survey.  This initiative was very successful with over 200 responses received.  Council has mobilised survey resources collected all data from this survey.

DPE have agreed to fund all the post event technical analysis.

The post event technical analysis will cover the Brunswick River, Belongil, Tallow Creek catchments and Bangalow. Consultants WMA have been commissioned by DPE for the Brunswick River catchment and BMT have been commissioned by DPE for the Belongil and Tallow Creek catchments. QIT, Council Emergency Dashboard provider have also been commissioned to undertake a post event analysis of Councils flood warning system.

There is a large amount of works involved to complete the post event technical analysis and current estimates from DPE and consultants is likely to take two to three months as a minimum.

DPE has recently extended their proposed delivery. Staff understand that many flood specialist consultants are experiencing staff change and staff resourcing issues which has caused delays.

Post such significant flood events it is natural that the industry will be under pressure from flood related areas including; insurance companies, developers and local governments.

Draft reports have been received by DPE and are currently undergoing quality assurance and technical review.


 

Key issues

·    Timing of works (reliance on DPE and third-party consultants)

·    Privacy of data

Next steps

·    Review draft post event technical analysis

·    Finalise reporting and report back to the Floodplain Management Advisory Committee

Financial Considerations

·    Council’s Flood and Drainage Engineer’s time and resource allocation

·    All other activities are fully funded by DPE and SES (approx. $150 000)

Consultation and Engagement

Community consultation has been in the form of digital flood survey mark requests via media releases and Council’s website.