Agenda of Floodplain Risk Management Advisory Committee

Reports submitted to the Floodplain Risk Management Advisory Committee to be held on Thursday 7 December 2023.

Floodplain Risk Management Advisory Committee AGENDA AND BUSINESS PAPER

Thursday 7 December 2023

ORDER OF BUSINESS:

CLAUSE PRECIS PAGE

ACKNOWLEDGEMENT OF COUNTRY 2

APOLOGIES 2

Confirmation of Minutes

CM-1 Floodplain Risk Management Advisory Committee Minutes - 19 October 2023 2

DECLARATIONS OF INTEREST 2

Reports from Staff

RP-1 2021-22-FM-0032 - Uranquinty Levee Upgrade - Investigation and Design 3

RP-2 2018-19-FM-0071 - North Wagga Flood Mitigation Options 5

RP-3 2021-22-FM-0024 - Glenfield Drain and Flowerdale Storage Flood Mitigation Works 6

RP-4 2021-22-FM-0039 - Lake Albert Flood Mitigation Options - Feasibility Study 8

RP-5 2022-FMP-0103 Humula and Mangoplah Flood Studies 10

RP-6 Local & Regional Risk Reduction Stream - Levee Pump Augmentation 12

RP-7 DPE Floodplain Manual Revision 14

RP-8 Flood Project Implementation Status 17

QUESTIONS WITH NOTICE 19

ACKNOWLEDGEMENT OF COUNTRY

Wagga Wagga City Council acknowledges the traditional custodians of the land, the Wiradjuri people, and pays respect to Elders past, present and future and extends our respect to all First Nations Peoples in Wagga Wagga.

We recognise and respect their cultural heritage, beliefs and continuing connection with the land and rivers. We also recognise the resilience, strength and pride of the Wiradjuri and First Nations communities

APOLOGIES

Confirmation of Minutes

CM-1 Floodplain Risk Management Advisory Committee Minutes - 19 October 2023

Recommendation

That the Minutes of the proceedings of the Floodplain Risk Management Advisory Committee Meeting held on 19 October 2023 be confirmed as a true and accurate record, noting Council’s adoption of these minutes at its meeting on 6 November 2023.

Attachments

1 ⇩.

FRMAC Committee Minutes

DECLARATIONS OF INTEREST

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-1

Reports from Staff

RP-1 2021-22-FM-0032 - Uranquinty Levee Upgrade - Investigation and Design

Author: Andrew Mason

Director: Phil McMurray

Summary:

The project is progressing as per the required program. Preliminary fieldwork and analysis has been completed.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the Uranquinty Levee project.

Report

Royal HaskoningDHV (RHDHV) have now completed the majority of the background investigations, this includes:

· Site inspection of the proposed levee alignment.

· Geotechnical investigations and boreholes along the alignment.

· Survey investigation of the levees.

· Services investigation of the levees.

· Review of hydraulic modelling files including results.

RHDHV have commenced with the preliminary design and freeboard analysis and have provided extensive commentary on this in their attached report.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Be responsive to emergencies

Risk Management Issues for Council

N/A

Internal / External Consultation

N/AN/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-2

RP-2 2018-19-FM-0071 - North Wagga Flood Mitigation Options

Author: Andrew Mason

Director: Phil McMurray

Summary:

The project is progressing well and the next stage of the community consultation will commence shortly.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the North Wagga Flood Mitigation Options Project.

Report

The consultant CIE and Woolcott have been working on the format and wording of the community and online survey. The feedback from FRMAC has been received and noted and the survey is currently underway and will be completed shortly.

The economic analysis has been completed and CIE have been working towards the developing the economic BCR of each option and once the community consultation has been completed and analysed, CIE will provide options to FRMAC to consider for adoption.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Be responsive to emergencies

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-3

RP-3 2021-22-FM-0024 - Glenfield Drain and Flowerdale Storage Flood Mitigation Works

Author: Andrew Mason

Director: Phil McMurray

Summary:

Lyall and Associates have provided an update on the project.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the Glenfield Drain and Flowerdale Storage Area Flood Mitigation Works Project.

Report

From Lyall and Associates:

“Council had asked us to provide him with a fee to update the structure of the City MOFFS model to make it fit for the purpose of identifying individual allotments as Flood Control Lots, noting that this refinement process would need to take place before we progressed further with the basin assessment process.

We provided Council with a variation under the main Glenfield Road Drain contract on Friday 24/11/23.

While we would need to review the key milestone dates, I anticipate that we will need to submit a time variation request given the time it will take us to update the structure of the model.”

If Council proceeds with this variation it will only be a time and scope variation to the DPE grant as the grant funding amount is fully allocated.

When the time variation is supplied to Council a variation will be submitted to DPE.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Be responsive to emergencies

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-4

RP-4 2021-22-FM-0039 - Lake Albert Flood Mitigation Options - Feasibility Study

Author: Andrew Mason

Director: Phil McMurray

Summary:

There is a slight delay in this project while the procurement and contract process are finalised.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the Lake Albert Flood Mitigation Project.

Report

A workplan and cost variation has been submitted to DPE for approval. The procurement process has been finalised and Stantec are beginning to collate data and analyse various flood models for the two creeks and the Lake. Once the workplans are approved then Stantec will begin planning the community consultation with the required key stakeholders and groups.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Be responsive to emergencies

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-5

RP-5 2022-FMP-0103 Humula and Mangoplah Flood Studies

Author: Andrew Mason

Director: Phil McMurray

Summary:

WMAWater have commenced the study for Humula and Mangoplah including a site visit with Council staff

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the Humula and Mangoplah Flood Studies Project.

Report

Council engaged WMAwater in late September 2023, to undertake the Humula and Mangoplah Flood Study. A project inception meeting and site visit was undertaken in early November with Council staff and the WMAwater team. This was a great opportunity for the project team to see the study area and understand the flood impacts experienced by the communities in the 2010 and 2012 flood events.

WMAwater are currently in the data collection phase and are working with Council to gather everything they need. Data being collected includes topographic information to build their understanding of the terrain and key hydraulic structures, rainfall and water level data, as well as photos and anecdotal information for previous events, and design event input from Australian Rainfall and Runoff.

It is planned to undertake some initial community engagement early next year and present an update to FRMAC at the first meeting in 2024. The community engagement will aim to keep the community informed about the start of the study and what the study will achieve, as well as gathering further information about the community’s experiences in previous flood events. This information is extremely valuable to the study and helps ensure that the study outputs are informative and usable for Council and the community.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Be responsive to emergencies

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-6

RP-6 Local & Regional Risk Reduction Stream - Levee Pump Augmentation

Author: Andrew Mason

Director: Phil McMurray

Summary:

A consultant has been appointed for this project.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the Levee Pump Augmentation Project.

Report

Stantec have begun work on this project.

The following steps have been completed or are currently underway:

· Site visit to 5 floodgates

· Topographic survey of sites, pipes and levee

· Flood model analysis commenced

· Gate 15A assessment completed

· Gate 15A preliminary drawings 50% complete

There will be a cost variation submitted by Stantec to cover extra work required to finetune the flood model to reflect changes in ground topography and updated LiDAR information.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Community leadership and collaboration

Objective: Wagga Wagga has strong community leadership and a shared vision for the future

Plan long term for the future of Wagga Wagga

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-7

RP-7 DPE Floodplain Manual Revision

Author: Andrew Mason

Director: Phil McMurray

Summary:

DPE have issued a new Flood Risk Management Manual.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the update of the Flood Risk Management Manual by the NSW Department of Planning and Environment.

Report

Flooding results in significant risk to many communities across New South Wales. This risk stems from human interaction with flooding through the occupation and use of floodplains.

Since 1984 the NSW Flood Prone Land Policy (the policy) has set the direction for Flood Risk Management (FRM) in New South Wales. In 1986 the NSW Government released the first Floodplain Development Manual to support policy implementation. The policy and manual have since evolved in response to significant flood events, reviews and improvements in national and international flood risk management practice.

This manual (including the policy) replaces the Floodplain Development Manual (DIPNR 2005) as the NSW Government’s manual relating to the management of flood liable land in accordance with section 733 of the Local Government Act 1993 (LG Act). This provides councils, statutory authorities, and state agencies and their staff, with indemnity for decisions they make and information they provide in accordance with the manual.

10 Council staff attended a regional Workshop conducted by DPE staff that included the following topics:

The new Flood Damage Assessment tool has been applied to the North Wagga Mitigation Options Study by the consultant to ensure we are using the most up to date information in the assessment

Council has a Status Report attached as an agenda item for this meeting.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Be responsive to emergencies

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 7 December 2023

RP-8

RP-8 Flood Project Implementation Status

Author: Andrew Mason

Director: Phil McMurray

Summary:

This Report outlines the status of the flood projects across the various studies that Council currently has underway.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the report in relation to Flood Project Implementation Status

Report

Council has over 60 recommendations from the three recently completed studies and is working its way through the studies . The spreadsheet tracking these projects is an attachment to this report.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Be responsive to emergencies

Risk Management Issues for Council

As outlined in the Report.

Internal / External Consultation

N/A