Agenda of Floodplain Risk Management Advisory Committee

Reports submitted to the Floodplain Risk Management Advisory Committee to be held on Thursday 16 April 2026.

Floodplain Risk Management Advisory Committee AGENDA AND BUSINESS PAPER

Thursday 16 April 2026

ORDER OF BUSINESS:

CLAUSE PRECIS PAGE

ACKNOWLEDGEMENT OF COUNTRY 2

APOLOGIES 2

DECLARATIONS OF INTEREST 2

Reports from Staff

RP-1 WWCC MOFFs FFL Amendment review 3

RP-2 2021-22-FM-0032 - Uranquinty Levee Upgrade - Investigation and Design 16

RP-3 2022-FMP-0103 Humula and Mangoplah Flood Studies 43

RP-4 DCCEEW 2024 Floodplain Grants 45

RP-5 17866- Levee System Upgrade - North Wagga 47

RP-6 2023 FMP 0073 Early Warning System Model Development 49

RP-7 2021-22-FM-0039 - Lake Albert Flood Mitigation Options - Feasibility Study 51

RP-8 2021-22-FM-0024 - Glenfield Drain and Flowerdale Storage Flood Mitigation Works 53

RP-9 Flood Project Implementation Status 55

QUESTIONS WITH NOTICE 83

ACKNOWLEDGEMENT OF COUNTRY

APOLOGIES

DECLARATIONS OF INTEREST

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-1

Reports from Staff

RP-1 WWCC MOFFs FFL Amendment review

Author: Sam Robins

General Manager: Peter Thompson

Summary:

Council has engaged GLN Planning and WMS Engineering to review the Flood Planning Area and the Finish Floor Level (FFL) in the MOFFs Study and Plan.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note that a detailed report is being prepared with the intent that it will be available for consideration at July’s meeting.

Report

Background:

Councils ‘Wagga Wagga Major Overland Flow Floodplain Risk Management Study and Plan 2021’ (MOFFs) makes a recommendation that the minimum appropriate freeboard for flood planning levels for properties is 0.3m above the 1% AEP.

This height came from discussions with the consultant and Council’s town planning staff and was based on the position that at the time this was generally consistent with what other Councils were applying.

Whilst no update to the Development Control Plan has occurred since the adoption of the study, Council’s practice has been to implement this recommendation. What we have found is that this decision raises the following issues:

· Impact on built form, overlooking, overshadowing

· Impact on accessibility of the building

· Impact on streetscape

· Impact on construction cost.

These factors have led to a view that the Finished Floor Level (FFL) is a restrictive factor in the development of brownfield sites and infill development within areas where other policy position supports and encourages intensification.

Council planning staff are of the view that there is a substantial difference between the impact of a riverine flood event and a MOFFs event and the marginal difference in freeboard does not reflect this.

Next Steps

Council is therefore requesting a review of this recommendation and of how the Flood Planning Area (FPA) was determined.

Details of the review and desired outcomes are as follows:

MOFFs modelling

· Review with the intent of removing isolated areas of the FPA created by the level of accuracy within the modelling. Provide a report that justifies the areas to be removed and ensures the recommended changes to the defined FPA remain consistent with the NSW Flood Risk Management Manual.

· Provide Council with advice on whether the edges of the current modelling can be ‘smoothed’, and if so, what would be the cost and time frames involved in this process.

· Provide Council with any other options (excluding remodelling) for improving the accuracy of the modelling in terms of defining the FPA.

MOFFs Study and Plan

· Review recommended FFL with the intent of reducing the requirement for a freeboard in certain circumstances.

· Provide a report that either:

o Supports the proposed amendment to the FFL recommendation and outlines the steps required to implement the amendment correctly, or

o Disagrees with the position to amend the FFL and provides explanation as to why.

· Ensure any recommendation remains consistent with the NSW Flood Risk Management Manual and therefore provide Council the protection it requires under section 733 of the Local Government Act 1993.

Council staff will present on the issue to the meeting.

Financial Implications

Council funding from internal budget.

Policy and Legislation

Environmental Planning and Assessment Act 1979

Local Government Act 1993

Link to Strategic Plan

Regional Leadership

Ethical Leadership

Provide strategic direction and leadership for our region to deliver key community priorities.

Risk Management Issues for Council

Ensure any recommendation remains consistent with the NSW Flood Risk Management Manual and therefore provide Council the protection it requires under section 733 of the Local Government Act 1993.

Internal / External Consultation

N/A

Attachments

1 ⇩.

MOFFS Amendment Presentation

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-2

RP-2 2021-22-FM-0032 - Uranquinty Levee Upgrade - Investigation and Design

Author: Andrew Mason

General Manager: Peter Thompson

Summary:

The project is progressing as per the required program. The 80% design is in progress an, the extension of the Connorton St section of the levee has been completed and a design report provided to Council for review.

Recommendation

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

Report

The 80% design is complete, Council and DCCEEW have reviewed the design and provided feedback to RHDHV .

RHDHV and Council staff presented the 80% design to the community of Uranquinty on the12th March, any appropriate feedback has been incorporated into the design as presented today.

Public Exhibition

A levee design does not normally require going to public exhibition, once Council and FRAMC accept the design then the project is complete and can move onto implementation. There is no budget allocation for RHDHV to put the design on Public Exhibition.

Once the 80% design is accepted by FRMAC and Council, RHDHV will progress the design and associated reports to conclusion and the final design will be will provided to Council in line with the current project timeline.

The following update has been provided by Royal Haskoning (RHDHV) who are the consultant engaged to deliver this project.

· The drawings and report are currently being updated to address comments received from Council. Expecting to have these addressed by the end of April.

· As part of the finalisation and an outcome from the community consult, we are including a section recommending prioritisation of the levee upgrade sections, based on maximising the benefit cost.

· We are finalising a draft version of the levee operation manual and Review of Environmental Factors that will be ready in the next week.

· Look to have the project wrapped up by the end of May 2026

RHDHV will be presenting the 80% design to this meeting.

Aboriginal Land Claim

The NSW Aboriginal Land Council has recently issued a claim over Crown land across many areas of the LGA. These claims include blocks of land that contain both the existing and potential future levee alignment. As per our current practice in this situation, Council will approach the Land Council to negotiate a solution for these parcels of land which will involve the removal of the relevant parcels from the claim or Council acquire an easement over the parcel for drainage, flood and maintenance purposes.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Regional Leadership

Ethical Leadership

Provide strategic direction and leadership for our region to deliver key community priorities.

Risk Management Issues for Council

N/A

Internal / External Consultation

N/AN/A

Attachments

1 ⇩.

Uranqunity Levee Upgrade presentation

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-3

RP-3 2022-FMP-0103 Humula and Mangoplah Flood Studies

Author: Andrew Mason

General Manager: Peter Thompson

Summary:

WMAWater have completed the modelling and reporting for the flood model for the study for Humula and Mangoplah and are seeking endorsement to place the model and report on Public Exhibition .

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update provided in relation to the Humula and Mangoplah Flood Studies Project and endorse the model and report to go on Public Exhibition

Report

Council engaged WMAWater in late September 2023, to undertake the Humula and Mangoplah Flood Study.

WMAWater have been preparing the reporting for the Mangoplah and Humula Flood Study. In preparing the report, it was identified that some additional model simulations were required. These have been progressed, and the Draft Flood Study report has been provided to Council.

WMA Water is seeking endorsement from FRMAC to place the report on Public Exhibition. The outcomes of the Public Exhibition will then be presented to the July FRMAC meeting for consideration and recommendation to Council to finalise the Flood Studies and complete the project.

A time extension until September 2026 has been approved by DCCEEW for this project. This allows time for Public Exhibition, FRMAC meetings and Council meetings.

WMAWater will be presenting to this meeting.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Regional Leadership

Ethical Leadership

Provide strategic direction and leadership for our region to deliver key community priorities.

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-4

RP-4 DCCEEW 2024 Floodplain Grants

Author: Andrew Mason

General Manager: Peter Thompson

Summary:

This Report provides an outline of the DCCEEW Floodplain Grant Applications for 2026

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the report with regard to the 2026-27 Floodplain Management Program.

Report

As at the end of August 2026 Council will have completed either the implementation or feasibility studies for the high priority recommendations from both the 2018 Riverine FRMSP and the 2021 MOFFS studies.

The DCCEEW FMP grant for 2026-27 has opened and Council needs to decide which project or study to apply for in this round of funding which closes on the 15^th April 2026. The choice of what to apply for is across the projects listed below:

· Utilise Reconnecting River Country program data, new LiDar and imagery to develop a new riverine flood model with a smaller grid size and a combination of 1D and 2D modelling

· Utilise data and information completed as a part of the Glenfield Drain flood mitigation project, the investigation into floodgate 25 and other more recent smaller studies, to develop a new, more comprehensive and detailed MOFFs flood model for the city including pipes and pits and stormwater infrastructure.

· Glenfield Drain Flood Mitigation projects, this capital intensive project has a total cost of $27M . Perhaps key individual projects such as PFMM1 (Flowerdale Storage Area supplementary pipes) can be delivered at a cost of approximately $1M

· Lake Albert Flood Mitigation Options. The detailed design for this project could be developed, this would require, an REF, topographic survey and civil, building and environmental design components. Funding for the construction of this project would then need to be another DCCEEW grant in future founds.

· Uranquinty Levee construction, the detailed design of the levee will not be finalised until the end of May 2026 so perhaps this funding should be sourced in future rounds of DCCEEW grants.

In 2025 DCCEEW received grant applications to the value of $46M and provided funding for $8M .

Council is due to renew both the Riverine and MOFFs models. The availability of an extensive amount of cost effective and current data and the increase in computing power since the current models were developed results in this project being the next important step in Council’s floodplain management program.

Council staff consider that, given the scale of these projects and the ongoing development pressures in both the northern and southern areas of the city, a staged approach is necessary. The approach will be to update and extend the existing MOFFS model for the 2026 grant funding and then the update of the riverine model will follow in 2027.

Financial Implications

A $600,000 grant application will result in Council needing to fund $200,000 of this project.

Policy and Legislation

N/A

Link to Strategic Plan

Safe and Healthy Community

Objective: Our community feel safe

Monitor and enforce public safety

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-5

RP-5 17866- Levee System Upgrade - North Wagga

Author: Andrew Mason

General Manager: Peter Thompson

Summary:

The project to upgrade the North Wagga levee has commenced with preliminary tasks completed and with some grant funding closures becoming due.

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the update to the Levee System Upgrade – North Wagga.

Report

A new project specifically about the implementation of the levee raising and third-party mitigation options has commenced.

The Project Sponsor is the Director Infrastructure Services.

An updated indicative timeline for the implementation of the raised levee and third-party mitigation options is provided below.

Stage	Duration	Commencement	Status
Topographic Survey	6 months	August 2024	Complete
Environmental Assessment	4 months	November 2024	Complete
Floodgate Pipe Relining	4 months	September 2025	Complete
Civil Design including mitigation options for residents adversely affected by the levee raising	6-12 months	December 2025	PWA NSW are the design consultant. Council will be negotiating with affected landholders
Levee contractor procurement	4 months	July 2026	Not due
Levee construction	24 months	November 2027	Not due

For the North Wagga levee, Council currently has a funding pool of:

· $6.1M in SRV funding

· $1.1M in the original Commonwealth Development Grant (CDG) to be expended by 30 June 2026.

· $9.1M in DRF round three funding

The CDG has been allocated to fund the floodgate pipe relining, the detailed design of the levee, purchase of sheetpiles and the purchase of 5 floodgates.

The status of the project is:

· The detailed survey for the levee design has been completed.

· The Review of Environmental Factors has been completed and accepted by Council

· The detailed design of the levee has been awarded to PWA NSW after negotiations with GHD failed to reach a successful conclusion.

· Pipeline Watertech have completed the relining of the existing 11 floodgates in the levee, the remaining three floodgates require significant levee work as well as the relining and this will be undertaken as a component of the levee rebuild.

· A project team has been engaged to oversee this complex project.

Financial Implications

N/A

Policy and Legislation

Local Government Act

Development Control Plan 2010

Flood Risk Management Manual

Link to Strategic Plan

Regional Leadership

Ethical Leadership

Provide strategic direction and leadership for our region to deliver key community priorities.

Risk Management Issues for Council

N/A

Internal / External Consultation

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-6

RP-6 2023 FMP 0073 Early Warning System Model Development

Author: Andrew Mason

General Manager: Peter Thompson

Summary:

This Report provides an update of the Early Warning System Model Development 2023 FMP 0073

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the report regarding the Early Warning and Flood Prediction Project.

Report

This project is a development of a recommendation from the 2018 FRMSP.

An initial project was completed by Stantec, and this has been developed into a specific and targeted approach to improve accessibility to flood and river data for the Council, the State Emergency Service and the public.

The approach is to enhance and improve existing Council systems and work collaboratively with the SES and Bureau of Meteorology to improve access to data across the Local Government Area and the wider catchment.

Worley was engaged to deliver the Early Warning and Flood Prediction project as an enhancement to the existing WaterRide software currently utilised by Council.

Status of project:

· Base Murrumbidgee River system operational

· Upstream lookup approach developed and to be integrated into WaterRIDE 11

· MOFFS flash flood base configuration complete

· Build URBS hydrology model (variation complete)

· Configuration of operational forecasting WaterRIDE projects complete

· Configuration of WaterRIDE LITE project complete

· Present beta version

· Setup/Delivery/Training/Manual complete

This initial project is complete and the system is up and running for Council staff to utilise. The public facing version of the software will be released shortly.

Council and Worley will continue to improve and enhance the system, Council has provided Sewer Pump Station data to Worley as critical action points where intervention is required by Council staff during emergencies.

Worley will be presenting the system and project to the FMA conference in a couple of weeks and also to the LEMC at their meeting on the 4 May 2026.

Financial Implications

The project is currently within budget allocations.

Policy and Legislation

N/A

Link to Strategic Plan

Regional Leadership

Ethical Leadership

Provide strategic direction and leadership for our region to deliver key community priorities.

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-7

RP-7 2021-22-FM-0039 - Lake Albert Flood Mitigation Options - Feasibility Study

Author: Andrew Mason

General Manager: Peter Thompson

Summary:

Work on this project is complete.

Recommendation

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

Report

Lake Albert Enhanced Flow Scheme – Feasibility Study

Stantec has been engaged by Wagga Wagga City Council to assess in further detail the feasibility of diverting additional flooding flows from Stringybark Creek and Crooked Creek and using Lake Albert to provide additional flood mitigation to the broader area, referred to as the ‘Lake Albert Enhanced Flow Scheme’.

This was first proposed as a flood mitigation option in the Wagga Wagga Major Overland Flow Floodplain Risk Management Study and Plan (MOFFRMS&P, WMA Water, 2021). The project has been divided into the following three stage sites:

· Stage 1 (LA01) Lake Albert Outlet Modification

· Stage 2 (LA02) Crooked Creek Modification

· Stage 3 (LA03) Stringybark Creek Modification

Stantec have completed the project and only Stages 1 and 3 are viable and prioritisation and funding for this project will need to be developed and sought by Council to implement this project.

Stantec are completing the design of some components of LA03 as a part of the Plumpton Road upgrade and these will be installed as that project progresses.

The Acquittal Report has been provided to DCCEEW to close out the project.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Regional Leadership

Ethical Leadership

Provide strategic direction and leadership for our region to deliver key community priorities.

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-8

RP-8 2021-22-FM-0024 - Glenfield Drain and Flowerdale Storage Flood Mitigation Works

Author: Andrew Mason

General Manager: Peter Thompson

Summary:

Lyall and Associates have completed the investigation into suggested mitigation options to reduce impacts in the Glenfield Drain catchment as identified in the Wagga Wagga Major Overland Flow Floodplain Risk Management Study and Plan (MOFFS).

Recommendation

That the Floodplain Risk Management Advisory Committee receive and note the report.

Report

The project has been completed and closed out with DCCEEW. Council is analysing components of this project for design and implementation . The design for the reconstruction of Glenfield Drain is complete and funding and prioritisation of the various components of this project and the upstream works is being determined by Council staff.

Financial Implications

N/A

Policy and Legislation

N/A

Link to Strategic Plan

Regional Leadership

Ethical Leadership

Provide strategic direction and leadership for our region to deliver key community priorities.

Risk Management Issues for Council

N/A

Internal / External Consultation

N/A

Report submitted to the Floodplain Risk Management Advisory Committee on Thursday 16 April 2026

RP-9

RP-9 Flood Project Implementation Status

Author: Andrew Mason

General Manager: Peter Thompson

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 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

Attachments

1 ⇩.

2023 Flood Studies Project Status