Agenda of Flood Management Advisory Committee

Flood Management Advisory Committee Meeting

28 May 2025

Minutes of the Flood Risk Management Advisory Committee Meeting – 26 February 2025

Directorate Name	Infrastructure
Date / Time	26 February 2025 - 3:00 PM
Venue	Microsoft Teams
Chairperson	Councillor Mat Howard
Voting Attendees	Clr Mat Howard	Clr Olivia Barlow	Michael Carney (SES)
Community Representatives


Non – Voting Technical Advisory Attendees	Ryann Midei (IWC)	David Paton (IWC)	James Ogg (IWC)
	Rafaah Georges (IWC)	Sadeq Zaman (DCCEEW)
	Claire Wheeler (CRA)	Michael Rosenthal (Rhelm Consulting)
Observers	Simon Myall	Tim Harnett	Jaan Ranniko
	Matthew Murphy	Bowen Hicks	Emily McGrath
	Pilar Lorenzo	Tiffanie Ong

Apologies	David Grasby (Sydney Water)	Lachlan Broadbent	Liam Hogan

1. 2. Acknowledgement Of Country – Clr Howard

I acknowledge that we are meeting on the land of the Gadigal and Wangal people of the Eora Nation and pay my respects to the elders past and present and I extend that respect and acknowledgement to any Aboriginal people who are here with us today.

3. Disclosures of Interest

Nil.

4. Confirmation of Minutes

That the Minutes of the Flood Risk Management Advisory Committee Meeting held on 24 July 2024 be confirmed.

The minutes were confirmed by Councillor Matt Howard and seconded by Michael Carney

5. Staff Reports

5. 1 - FMACC0724(1) Item 1 Outstanding Actions Register

SUMMARY

The following table provides the status of outstanding actions from previous Flood Management Advisory Committee meetings.

Meeting	Item	Actions	Comments	Status
29/2/24	4.1	That the Flood Management Advisory Committee endorse the updated Terms of Reference subject to replacing Transport for NSW Roads with Transport for NSW.	The Terms of Reference were adopted by Council at its meeting on 9 April 2024	Completed
29/2/24	5.1	That the Flood Management Advisory Committee support the schedule of actions to be taken to facilitate flood education within Inner West Council.	Noted	No action required
29/2/24	5.2	That Council develop communications regarding flooding and relevant services in the local area including the SES that can be made available through customer service centres, libraries and be made available to local real estate or rental agencies for new residents to the local community	An update will be provided at the next Committee meeting	In Progress
29/2/24	5.3	That Council better support and promote the activities of the SES, including in our local newsletter.	An update will be provided at the next Committee meeting	In Progress
29/2/24	5.4	That in the development of the Flood Information Hub, Council work to make emergency information for accessible and visible, that Council investigates the reporting of local road closure information.	An update will be provided at the next Committee meeting	In Progress
29/2/24	5.5	That the proposed information sessions undertaken with the Alexandra Canal Flood Risk Management Study and Plan and Johnstons Creek Whites Creek Flood Risk Management Study and Plan be undertaken with SES Officers.	SES Officers participated in the four information sessions during the exhibition period.	Completed
29/2/24	5.6	That Council investigate the publication of evacuation routes among consideration of public signage.	An update will be provided at the next Committee meeting	In Progress
29/2/24	5.7	That Council engage directly with community groups on the foreshore impacted by flooding.	An update will be provided at the next Committee meeting	In Progress
29/2/24	7.1	That the Flood Management Advisory Committee endorse the public exhibition of the Alexandra Canal Flood Risk Management Study and Plan.	Council resolved to exhibit the Study and Plan at its meeting on 9 April 2024. Exhibition is now complete, with its outcomes being tabled at July committee meeting	Completed
29/2/24	7.2	That the Flood Management Advisory Committee endorse the public exhibition of the Johnstons Creek and Whites Creek Flood Risk Management Study and Plan	Council resolved to exhibit the Study and Plan at its meeting on 9 April 2024. Exhibition is now complete, with its outcomes being tabled at July committee meeting	Completed

OFFICERS RECOMMENDATION

That Flood Management Advisory Committee receive and note the report.

DISCUSSION

Item 5.2. and 5.3 actions are still in progress. Item 5.4 has been deferred in its development as council undergoes a website review. Item 5.7 is in progress within the LGA and item 17.2 as per the outstanding actions register for 26 February 2025 regarding flooding in Despointes Street is still being investigated and in progress with further update to be provided in the next meeting.

Michael Carney raised an issue regarding letting SES attend council events, SES is not receiving any information on events happening in the area.

Request for Michael Carney to receive the contact details of who to speak to, to pass along email address of the units.

James Ogg to action and speak to the events team and Michael Daley.

COMMITTEE RECOMMENDATION

Councillor Barlow moves the action register and seconded by Michael Carney.

For Motion: Unanimous.

5.2 - FMACC0225(1) Item 2 Update on adopted Flood Risk Management Plan Options

SUMMARY

To date, Council has completed and adopted nine Flood Studies and six Flood Risk Management Studies & Plans (FRMSP) across 90% of the Local Government Area including:

• Eastern Channel Subcatchment Management Plan (Golder Associates, 2011)

• Leichhardt Flood Risk Management Study & Plan (Cardno, 2017)

• Marrickville Valley Flood Risk Management Study and Plan (Cardno,2017)

• Dobroyd Canal & Hawthorne Canal Flood Risk Management Study and Plan (WMA, 2019)

• Whites Creek & Johnstons Creek Flood Risk Management Study and Plan (Stantec, 2024)

• Alexandra Canal Flood Risk Management Study and Plan (Stantec, 2024)

Marrickville South is the only catchment of the Inner West LGA without a contemporary flood study or flood risk management plan. Council has been successful in securing two-thirds grant funding from the Department of Climate Change, Energy, the Environment and Water to support the delivery of this Flood Study. Council will be issuing a request for quotation to engage specialist flood consultants in early March.

The completed Flood Risk Management Studies and Plans propose a total package of structural mitigation measures valued at approximately $300 million across assets owned by Council and other utilities, with 26 options considered high priority totalling approximately $105 million.

Council currently budgets $1.5 million to stormwater upgrade projects addressing local catchment issues as well as some of the smaller mitigation investigations and design. Council seeks additional funds through state and federal grants to supplement this work, however due to the limited funding available through these grants, or the increasing level of detailed design required to support such a grant, this is generally beyond the financial capacity of Council to deliver in the short to medium term without significant impact on other Council services.

Currently the primary management actions to manage and mitigate the impact of flooding are therefore primarily dependent on non-structural measures such as planning controls, emergency response planning and reactive maintenance including undertaking CCTV and cleaning of stormwater assets.

OFFICERS RECOMMENDATION

DISCUSSION

Council Officer advised the report outlines what the flood risk management process is, the process is guided by the Department of climate change, energy, environment and water. Council through its floodplain risk management and its officers look after flood risk management within the local government area which is carried out across different stages. A flood study is carried out, which has been done for ~90% of the LGA, before moving to a floor risk management study and flood risk management plan. The study indicates where hazards are, where evacuations may need to be thought through and what measures to reduce or plan for risk. The study reviews all potential options, impacts the options may have and makes a cost benefit analysis and multi criteria analysis to come up with a list of prioritisation within the study for council to pursue and determine which plans are implemented.

Council Officer advises the works are undertaken by Council and the Department of Climate Change, Energy, Environment and Water provide 2/3 grant funding for these activities, in 2024 there was approximately 10 millions in grants on offer for the state, this is a competitive grants process and must be applied for each year. Stormwater fund is separate, council has funds committed, approximately 1.5 million for stormwater renewal for all stormwater assets and about 1 million for stormwater upgrades.

Community member Simon Mya raised concerns regarding extreme flooding in Hearn Street Leichhardt on February 10^th, and noticed the area was not covered by the study from last year in, and despite flood study carried out in 1990 around the Whites Creek catchment area included severe observations around flooding in the area which is still recurrent now, and enquires why it is still not covered in the new 2024 report.

Council Officer advises the Hearn Street was part of a previous study started by Leichhardt Council at the time, to which Hearn Street in particular is within the Leichhardt flood risk management study and plan. The 2024 Whites Creek and Johnston Street flood risk management plan focused on areas south of Parramatta Road.

Simon Mya questioned if there were no actions proposed for the Whites Creek catchment area as part of the earlier study.

Council Officer advises no actions were listed specifically within the previous study plan. Hearn Street backs on to Whites Creek, which is part of what causing flooding, the Sydney water channel runs at a particular capacity and how swiftly water can drain into the channel once it is full. There were options in and around Whites Creek, contingent around upgrades around the channel itself to relive pressure downstream.

Simon Mya raised concerns that in the 2024 study, many of the proposed actions were upstream of the Whites Creek area which could potentially exacerbate flooding issues in Hearn Street and downstream north of Parramatta road, and this issue has not be addressed.

Council Officer notes, any option upstream has to demonstrate that works will not impact downstream. This excludes many options, for much of Whites Creek there is only one options in the Whites Creek management plan that was adopted in 2024 as there is only a small portion that sits below Parramatta Road, all the items within Whites Creek are within the Leichhardt flood risk management study and plan as Hearn Street areas above Parramatta Road were part of the former Leichhardt Council who commenced the Leichhardt flood risk management study ahead of Marrickville and Ashfield.

Councillor Howard recommend James Ogg and Simon Mya discuss this after the meeting regarding further queries.

Simon Mya requested for clarification regarding if the action plan was still open and under review, James notes that the table within item 2 in the report speaks to the different flood risk management plans, and the Leichhardt management plan includes parts of Hawthorne Canal, Whites Creek and Johnstons Creek and areas around Hearn Street and above Parramatta Road was included. 8 flood risks management plans have been carried out to date, Marrickville South, and the areas around Dulwich Hill, the flood study is set to commence this year. The last two catchments being William Street and Cooks River are small contributors to other catchments and other councils, a small portion of land in Croydon that drains into Canada Bay and portion of Ashfield that drains into Canterbury Bankstown, but these are minor contributor catchments and will not be looking into details for those. Each of the 8 flood risk management plans proposed certain options, there is about $80-90 projects for all those with a projected cost of ~300 million, and the high priority options with a projected cost of ~$100-105 million. Part of prioritising that is working out where council can deliver most impact fastest, or, the larger multi million dollar projects in Leichhardt involves correspondence and engagement with Sydney Water as the larger dollar value projects are on Sydney Water Assets. Each of the 8 plans has a ranking and prioritisation within the plan itself, moving forward the outcome is to rank all the projects against each other on the same scale to formally prioritise them. From the current plans, Council this year has completed and upgraded Centennial Road, inlet upgrade in Northcote Marrickville, works in Fitzroy Street, stormwater replacement and upgrade in Wardley Street Balmain. There are project scheduled to happen this year in Haberfield and Enmore, and Victoria Road and Railway Parade in Marrickville. Council is also progressing designs this year for Illawarra Road, Addison Road and Edgeware Road, the three designs came from the Marrickville and Eastern Channel flood risk management plan. Council as advises in response to the stormwater and flooding from last year, there is another 6 upgrade designs progressing for construction next year. The flood mitigation options are done with the stormwater upgrades.

COMMITTEE RECOMMENDATION

Council Howard declares a non-significant and no pecuniary interest in this item as he does not reside within the area of concern. The report is just being notes, no funding decisions are being made,

Councillor Barlow moved the report and Michael Carney seconded.

For Motion:

Unanimous

5.3 FMACC0724(1) Item 3 LOCAL INCIDENTS OF FLOODING ON 10 FEBURARY 2025

SUMMARY

This report supports the following strategic directions contained within Council’s Community Strategic Plan: 1: An ecologically sustainable Inner West 2: Liveable, connected neighbourhoods and transport

At approximately 12pm on Monday 10 February Sydney experienced widespread thunderstorms affecting homes and flooding roads, including areas of Inner West Council. Rainfall data from nearby rain gauges at Sydney Olympic Park, Canterbury Racecourse and Sydney Observatory indicates that approximately 25mm water fell over the Inner West over the course of 30 minutes. This dispersion of rain is approximately equivalent to a 20% AEP event. Council has received 133 requests related to stormwater and flooding since this event. 46 of these requests have since been completed, with a further 54 in progress at the time of this report. The remaining requests require further investigation to determine possible civil works in the short and medium term. These requests primarily came from Leichhardt, Marrickville. Annandale and Ashfield.

Many of these requests related to blocked stormwater pits and inlets resulting from heavy leaf drop due to strong winds in late January, which consequently limited the speed at which water could be drained away from the roadway.

OFFICERS RECOMMENDATION

Council Officer advises that the increase flooding on Illawarra Road between Hill Street and Wharf Street has been noted and this will be investigated, and continue to raise issue on Railway Terrace with TfNSW through the local emergency management committee. Information was provided to TfNSW around the catchment around that space and they are investigating ways to improve the inlets and this will also be reviewed before committing to work.

DISCUSSION

The table within the report provides a breakdown of the suburbs that were mainly affected, a big concentration within the Leichhardt, Marrickville, with Annandale and Ashfield being with the impacted areas.

Council Officer notes one of the factors seen was high number of report of leaf litter or blocked pits that resulted from strong winds in January. The report lists multiple areas where resident reported the same flooding area, this included Darley Road and Elswick Street, Leichhardt, Station Street Petersham, Queen Street / Pyrmont Street, Holden Street / Palace Street, Ashfield, Probert Street Camperdown, Camden Street Enmore and Newington Road Marrickville. Some of these locations where already known to Council through the flood risk management study of previous events. Council is in progress of designing and delivering upgrades in four of these location. Camden Street Enmore is expecting a stormwater upgrade in April, Pyrmont and Queen Street, council has commenced community consult on the proposed design that has happened within the last week and the design is expected to be completed later this year for construction late 2025. Elswick Street, Council expects to construct early 2026, similar to Holden and Palace Street. The remaining three streets, Station Street Petersham, Probert Street Camperdown and Newington Road, more assessment is be undertaken and this will be included in future capital works programs. Darley Road, which is a state road and Council has informed TFNSW regarding on going risks and the request Council has received.

Michael Carney raised concerns of increased flooding at Illawarra Road Marrickville between Hill Street and Wharf Street over the last 18 months which previously did not occur. Requesting for investigation if the pits need cleaning or another issue. In regard to TFNSW, Michael has raised a discussion point about Railway Terrace at Petersham, and an increase in flooding and there will be shared infrastructure at that location and is waiting to hear back.

COMMITTEE RECOMMENDATION

For Motion:

Michael Carney moves the report and seconded by Councillor Barlow

Unanimous

5.3 FMACC0225(1) Item 3 Local Incidents of Flooding on 10 Feburary 2025

SUMMARY

Presentation from Cooks River Alliance by Michael Rosenthal from Rhelm Consulting.

OFFICERS RECOMMENDATION

DISCUSSION

A recent study was undertaken as part of the coast management program for the Cooks River looking at inundation from the coastal side.

The coastal management programme is led by the state government and developed over 5 stages, the inundation hazard assessment sits in stage 2 of the programme, the study is currently moving from stage 2 to 3, and identifying and evaluating options for inclusion in the coastal management programme. The CMP will be publicly exhibited and certified by the Minister to allow councils to access grant fundings. The coastal management programme is being built around 9 values which were identified through community and stakeholder consultation, flood resilience is one of the 9 value themes of which is specifically relevant to the Flood management advisory committee.

The CMP study area for the Cooks River spans 6 councils and cover the entire catchment of the Cooks River. As part of stage 2, the inundation hazard assessment was carried out with the purpose of talking to all the councils involved with the CMP to determine a fit for purpose methodology that works for everyone and identifying appropriate sea level rise scenarios to consider within the study and mapping coast and tidal inundation. The maps were then used to do a first pass on assets and infrastructure exposure assessment under the different types of flooding. The CMP looked at different scenarios, for tidal inundation a focus on high water of spring, looking at present day sea level 0.2m, 0.5m and 0.9m, for costal inundation for event based flooding, looking at present day, 5, 10 and 100 year storm.

The map shown provides an overview of present day coastal inundation, note, many of these areas that would be impacted by a coastal storm are much more impacted by catchment flooding, and some of these areas are already known problem areas when it rains.

Tidal inundation (sunny day flooding) was another area of flooding that was looked at. Haberfield is not within the study area for the Cooks River, but a known location where high high tides are can come up through the stormwater system and impact the roads. The study looked at where in the Cooks River area is the to happen more and more frequently. Tidal inundation become more frequent over time with sea level rise and is there to stay. It starts by coming up through the stormwater system and eventually peaking into the low points of road and eventually overtopping the bank and surpassing the stormwater system entirely.

The study look at different areas that would be impacted by overbank flooding and backwater flooding, differentiate between areas that management at the stormwater system could be used to mitigate flooding and areas where more topographical changes are needed to limit the flooding. Another idea explored was the drainage window concept, where the invert and overt of the stormwater outlet when submerged in low tide, the water in the catchment cannot drain out and over time the drainage capacity of the systems is reduced, and to look at further investigation and adaptation would need to occur.

When looking at the pits and pipe system to determine areas that might be exposed to back water flooding, a caveat to the assessment was that they were unaware of floodgates or assume any losses to the system. Key areas around the study area were looked at, the study looked at asset exposure to get a picture of the risk for each of the areas. The study also looked at days inundated, the map indicated areas that are frequently inundated and areas that are not frequently impacted. The map of Marrickville shows with 0.9m of sea level rise, the drainage window concept means the stormwater drainage efficiency with the boundary conditions in the channel would mean the draining is diminished and drainage capacity diminished.

Rhelm Consulting has spoken to all the councils affected by this issue and for this information to be brought to the flood committee. This study will need to be released to the public domain but before doing so are seeking councils guidance on the best way to do this, and what is council’s longer term response to this issue and be part of the stage 2 of the CMP. The CMP development is expected to take another 9 -12 month before it is out for public exhibition.

The main points brought to the committee, is that the notification of the study and the stage 2 study and the maps need to be released to the public and cooks river alliance will facilitate that. The approach being to prepare and circulate public facing fact sheet/web copy to support release of the study to help guide the community. Once the Councils who are affected by the issue have the information and comfortable with the fact sheet to then upload their reports to the CMP website.

Council Officer clarifies where council sits with this study. Council received the information within the last couple of weeks and have carried out preliminary looks in terms of the areas affected, and there are properties already in the area that have been tagged for known inundation. At this stage the study does not speak to planning changes, this is a risk identification study and not a response study. There are features that don’t take into account existing infrastructure to such as flood gates or flood valves to stop tidal flows around the Marrickville space.

Council Barlow requests a copy of the presentation.

Ryann Midei advises this is just early consultation for information purposes, there is still discussion and approval processes from a council perspective before this is shared.

COMMITTEE RECOMMENDATION

For Motion:

Councillor Howard notes the report and seconded by Councillor Barlow.

Unanimous

6. General Business

Jaan Ranniko raised query regarding the flooding issue at Illawarra Road, and the drains at Cahill Place appear to have minor damages and request for that to be looked at.

Raised enquiry regarding tidal inundation, and will backfill and cause more floods and where more information could be found regarding this.

Council Officer advises that Marrickville was a former swamp land and there is a low lying area that cannot drain by gravity itself, and drainage from Marrickville is pumped out to the Sydney Basin. There are no invert levels in the pipe, as such the pipe is higher than the river and does not have the same impact as the report may show.

Councillor Barlow notes that as per the forum held in Ashfield, there are a few places notes for overland flooding that had not flooded before or to the extend that it was. The streets mentioned include Arthur Street, Abergeldie Street and Holden Street which are both known overland risk areas.

Ryann Midei advised that a register of enquiries that were made and officer already making calls.

Tim Harnett raised the issue regarding fallen trees on the road at the bottom of Hearn Street which is blocking the drainage channel which is exacerbating the flood risk at the junction of Albion Road and Hearn Street and the clearing of leaves appears to be on an 8 week rotation that does not appear to be enough to clear the drainage channels.

Councillor Howard request for Ryann and team to action to look at the frequency to which the works are being carried out. Ryann has advised that there is a scheduled run of sweeping footpath and cleaning roads in areas which there is a larger amount of leaf matter, and this can be looked at to be done more frequently.

Tim Harnett also notes Wardell Road Petersham that the flooding is becoming more pronounced and the frequency of clearing of leaves may be a factor to this.

Meeting Closed: 4:08pm

Flood Management Advisory Committee Meeting

28 May 2025

Item No: FMACC0525(1) Item 1

Subject: Outstanding Actions Register

Prepared By: Rafaah Georges - Project Engineer - Stormwater & Emergency Planning

Authorised By: David Paton - Engineering Services Manager

RECOMMENDATION

That the Outstanding Actions Register be received and noted.

Meeting	Item	Actions	Status	Comments
FMAC 29/02/24	5.2	That Council develop communications regarding flooding and relevant services in the local area including the SES that can be made available through customer service centres, libraries and be made available to local real estate or rental agencies for new residents to the local community	In Progress	Council’s existing web page for emergency information has been updated to include information links to support services like SES and Red Cross. Emergencies - Be prepared - Inner West Council
FMAC 29/02/24 5.4	5.4	That in the development of the Flood Information Hub, Council work to make emergency information for accessible and visible, that Council investigates the reporting of local road closure information.	In Progress	Planned road closures are currently reported to state agencies and digital mapping services via the NSW Government OneRoad portal. Council will review capacity to provide similar updates for Emergency operations.
FMAC 29/02/24	5.6	That Council investigate the publication of evacuation routes among consideration of public signage.	In Progress
FMAC 29/02/24	5.7	That Council engage directly with community groups on the foreshore impacted by flooding	In Progress
Ordinary Council 12/11/24	C1124(1) Item 17.2	That Council investigate placing stoppers (at Despointes Street, Marrickville) to maintain the ability for the rainwater to enter the drain without being diverted onto the footpath and ponding creating a safety issue.	Completed	Existing road width does not allow for parking spaces to be provided with wheel stops while remaining compliant with Australian Standards. An alternative design to extend the stormwater drainage and increase inlet capacity has been prepared for future detailed design, subject to grant funding.
Ordinary Council 12/11/24	C1124(1) Item 26.6	That Council provide for members of the public to present to the Flood Risk and Management Committee on flood related matters by establishing a public forum, as is the case with the Inner West Council Traffic Committee.	In Progress	Report provided to the Committee at this meeting for initial discussion.
Ordinary Council 18/02/25	C0225(1) Item 39	That Council officers list flooding at Northcote Street and area flooding at the next Flood Management Advisory Committee, including the extent of flooding, mitigations currently in place and future options to mitigate and manage flooding	Completed	Report provided to the Committee at this meeting.
Ordinary Council 18/02/25	C0225(1) Item 39	That Council request officers report to the April Council meeting with information and future options to mitigate and manage flooding at Northcote Street, Marrickville	Completed
Ordinary Council 11/03/25	C0325(1) Item 40.1	That Council develop a plan for safe and effective flood management across Evan Jones Playground and Whites Creek Lane, Leichhardt and upgrades to the infrastructure in this playground and street, including: a) reviewing and reporting on the timeline	Completed	Report provided to 20 May Council meeting.
Ordinary Council 11/03/25	C0325(1) Item 40.2	That Council report the plan for flood improvement for Evan Jones Playground and Whites Creek Lane, Leichhardt to the May 2025 Council meeting.	Completed	Report provided to 20 May Council meeting.
Ordinary Council 29/04/25	C0425(1) Item 7.1	That Council receive the minutes and adopt the recommendations of the Flood Management Advisory Committee held on 26 February 2025	Completed
Ordinary Council 29/04/25	C0425(1) Item 7.2	That Council approve appointment of the Community Representatives to the Flood Management Advisory Committee.	Completed
Ordinary Council 29/04/25	C0425(1) Item 30.1	That Council receive and note the report for flooding in the area of Northcote Street, Marrickville	Completed
Ordinary Council 29/04/25	C0425(1) Item 30.2	That Council write to residents of Northcote Street to provide an update on actions being undertaken to address flooding in the area of Northcote Street, Marrickville	In Progress	Draft Letter prepared at time of publication.
Ordinary Council 20/05/25	C0525(1) Item 19.1	That Council receive and note the report - Flood Management Plan for Evan Jones Playground	Completed
Ordinary Council 20/05/25	C0525(1) Item 19.2	That Council write to Sydney Water requesting updated costing associated with upgrading of the Whites Creek stormwater channel.	In Progress
Ordinary Council 20/05/25	C0525(1) Item 19.3	That Council identify grant funding options available, and preparatory work that would be needed to apply for such grants, to fund these upgrades.	In Progress
Ordinary Council 20/05/25	C0525(1) Item 19.4	That Council report the outcomes of these engagements to Council in August 2025.	In Progress

ATTACHMENTS

Nil.

Flood Management Advisory Committee Meeting

28 May 2025

Item No: FMACC0525(1) Item 2

Subject: FLOODING IN THE AREA OF NORTHCOTE STREET MARRICKVILLE

Prepared By: James Ogg - Stormwater and Asset Planning Coordinator

Authorised By: Manod Wickramasinghe - Acting Director Engineering

RECOMMENDATION

That Flood Management Advisory Committee receive and note the report.

STRATEGIC OBJECTIVE

This report supports the following strategic directions contained within Council’s Community Strategic Plan:

1: An ecologically sustainable Inner West

2: Liveable, connected neighbourhoods and transport

4: Healthy, resilient and caring communities

EXECUTIVE SUMMARY

Residents have experienced flooding in Northcote Street and Malakoff Street on several occasions since February 2022, affecting several properties and flooding vehicles parked in the street.

Following initial consultation with residents in 2022, stormwater upgrade works were planned and completed in November 2024 at a cost of approximately $180,000 to increase drainage capacity in Northcote Street, which has improved the capture of stormwater within the street and reduced the length of time that flood waters remain in the street.

Further works within Carew Lane and Malakoff Street are included in the draft FY26 budget in the amount of $240,000.

Despite the completed works having improved the drainage system in Northcote Street, the capacity of the stormwater channel running between Northcote Street and Malakoff Street remains a constraint on the system and impacts on the effectiveness of the above works.

The Marrickville Valley Flood Risk Management Plan includes a proposal to divert and upgrade the existing stormwater pipelines within Jarvie Park and Petersham Road to further reduce flood risk in Northcote Street at an estimated cost of $800,000.

Funding has been included in the draft FY26 budget for feasibility assessment of a more targeted pipeline diversion within Jarvie Park, which could potentially be delivered at a lower cost. The results of this investigation would be presented to Council ahead of budget considerations for FY27 and beyond.

BACKGROUND

At the Council meeting held on 18 February 2025, Council resolved the following:

1. That Council note the ongoing flooding of streets in Northcote and surrounding streets.

2. That Council acknowledges the work undertaken by Inner West Council to increase the intake capacity of stormwater on Northcote Street in the 2024-2025 Budget.

3. That Council request officers list flooding at this location for discussion at the next Flood Management Advisory Committee, including the extent of flooding, mitigations currently in place, and future options to mitigate and manage flooding at the location.

4. That Council request officers report to the April council meeting with information and future options to mitigate and manage flooding at this location.

5. That Council write to Sydney Water requesting a meeting to discuss options to improve the capacity and effectiveness of the water channel that runs through the area.

Council Engineers have been consulting with the residents of Northcote Street and Malakoff Street since flooding impacted several properties and flooding parked vehicles in the street in February 2022. Drainage upgrade works were completed in Northcote Street in November 2024, improving the capture of stormwater and reducing the length of time that flood water remains in the street.

However, the stormwater channel that runs between Northcote Street and Malakoff Street, runs full in significant storms and impacts on the effectiveness of the recently completed works.

Council staff met with representatives from Sydney Water in March this year to discuss the concerns of the local residents, along with flood mitigation options.

DISCUSSION

History of Flooding at this Location

Inner West Council is a highly urbanised Council, with much of the area subdivided and developed prior to current awareness and understanding of long-term rainfall patterns and intensity. Many residential areas have been built either immediately adjacent to or across major creek lines which were channelised in the early 1900s.

This has resulted in many areas across the Local Government Area that have ongoing exposure to latent flood risk to varying degrees.

Specifically, Northcote Street is situated within a local low point of a major tributary to Cooks River via what was, prior to the industrialisation of Marrickville, the Gumbramorra Swamp. Inner West Council now calls this catchment Marrickville Valley, draining to the Sydney Water pumping station in Sydenham before being pumped out to Cooks River.

The portion of catchment draining to this location is in the order of 140 hectares and extends to New Canterbury Road. In the 1960s the Department of Public Works constructed a 1.9km underground channel which intercepted the open channel just upstream of Malakoff Street and diverted stormwater directly to Cooks River at Thornley Street, rather than via the Western Channel in Carrington Road.

Attachment 1 outlines the depth and extent of flooding affecting the area from Northcote Street to Garners Avenue. The figures are extracted from Council’s Marrickville Valley Flood Risk Management Study.

In February 2022, Inner West Council experienced significant flooding across areas of Marrickville, including Northcote Street and Malakoff Street, and was one of 61 Councils included in the Declared Natural Disaster AGRN 1012 - NSW Severe Weather and Flooding: 22 February 2022 onwards.

Current and Future Mitigation Options

Following the flooding in February 2022, Council developed plans to improve the capacity of the existing pits and pipelines directly draining Northcote Street and Malakoff Street. This was split into three projects with design and delivery to be staged between 2023 and 2026.

1. Pipe replacement and inlet upgrades in Northcote Street – Designed FY24 and delivered November 2024

2. Pipe renewal and new pits in Carew Lane – To be delivered FY26

3. Inlet Upgrades in Malakoff Street – New pits connecting directly to Sydney Water infrastructure in Malakoff Street. Designed by Council and approved by Sydney Water for construction in FY26.

The Marrickville Valley Flood Risk Management Study and Plan was adopted by Council in 2018. Council has been progressively investigating the feasibility of the options proposed in the Plan, including high priority items between Despointes Street and Silver Street, and Illawarra Road and Shepherd Street.

The Flood Risk Management Plan includes a further option within Jarvie Park as a medium priority item (Item FM3.1). The project would upgrade pipelines in Petersham Road and intercept existing stormwater pipelines from Cecilia Street and Depot Lane within Jarvie Park to drain directly to the Malakoff Street underground channel downstream of Northcote Street. It is anticipated that this would divert 23 hectares (approximately 15% of the total catchment) away from Northcote Street and reduce flood levels of up to 100mm in the 1% AEP flood event.

Council has been prioritising the development of High Priority options across the Local Government Area. Consequently, this option does not currently form part of Council’s Long Term Financial Plan or Delivery Program. The total estimated cost of this option is roughly $800,000, which would impact on the delivery of flood mitigation works elsewhere in the Inner West Council area.

The report to Council on the 29 April 2025 proposed that an initial investigation and feasibility study for this option be brought forward to be undertaken as part of the FY26 Operational Plan to review the scope of works and develop a more targeted measure that could potentially be delivered at a lower cost. This has been included within the Draft Budget currently on exhibition, noting that formal approval by Sydney Water would be required for any connections to the stormwater infrastructure in Malakoff Street.

Council’s Director Infrastructure, Engineering Services Manager and Coordinator Stormwater & Asset Planning met with representatives from Sydney Water in March this year to discuss the concerns of local residents, along with the above mitigation option. The Sydney Water representatives supported the proposal in principle and are committed to working with Council and the community to support measures to improve flooding in the area.

The Draft Budget also includes further investigation and design of downstream inlet improvements and upgrades in Despointes Street, Illawarra Road, Silver Street and Sydney Street, in addition to the physical works in Carew Lane and Malakoff Street outlined above.

Council considered the above matters at the 29 April 2025 Council Meeting and subsequently resolved:

1. That Council receive and note the report.

2. That Council write to residents of Northcote Street to provide an update on actions being undertaken.

These letters to residents are currently being prepared.

FINANCIAL IMPLICATIONS

The renewal of the pipeline in Carew Lane and upgrade of stormwater inlets in Malakoff Street are included in the draft budget for FY26 in the amount of $100,000 and $140,000 respectively.

An amount of $60,000 has been included in the draft budget for FY26 for the feasibility assessment and detailed design of the Jarvie Park stormwater diversion works. An application for funding is being made through the NSW Flood Recovery and Resilience Grant Program to support this work.

ATTACHMENTS

1.⇩

Map of Flood Extents and Depths around Northcote Street

Flood Management Advisory Committee Meeting

28 May 2025

Item No: FMACC0525(1) Item 3

Subject: Flooding in the Area of Evan Jones Park

Prepared By: James Ogg - Stormwater and Asset Planning Coordinator

Authorised By: Manod Wickramasinghe - Acting Director Engineering

RECOMMENDATION

That Flood Management Advisory Committee receive and note the report.

STRATEGIC OBJECTIVE

This report supports the following strategic directions contained within Council’s Community Strategic Plan:

1: An ecologically sustainable Inner West

2: Liveable, connected neighbourhoods and transport

4: Healthy, resilient and caring communities

EXECUTIVE SUMMARY

On Monday 10 February 2025, Sydney experienced widespread thunderstorms affecting homes and flooding roads, including areas of Inner West Council.

Community members have reported extensive overland flow from Evan Jones Playground into the lane, together with the lid of the gross pollutant trap (GPT) near Evan Jones Playground dislodging and causing a dangerous hazard. Additionally, there has been debris accumulation, including soft-fall wood chips from the playground, regularly blocking the drainage system and impacting on flooding.

A subsequent investigation was conducted to examine opportunities to minimise flooding impacts on Evan Jones Playground and Whites Creek Lane. The primary mitigation options involve significant upgrades of the trunk drainage systems which are cost prohibitive to upgrade.

Therefore, the available actions to manage and mitigate the impact of flooding are non-structural measures such as planning controls, emergency response planning and inspection and maintenance of stormwater assets. To reduce the impact of future event, maintenance activity to the playground and gross pollutant trap (GPT) have been completed.

BACKGROUND

On Monday 10 February 2025, Sydney experienced widespread thunderstorms affecting homes and flooding roads, including areas of Inner West Council.

Rainfall data from nearby rain gauges at Sydney Olympic Park, Canterbury Racecourse and Sydney Observatory indicate that approximately 25mm water fell over the Inner West over the course of 30 minutes. This dispersion of rain is approximately equivalent to a 20% AEP event (sometimes known as a 1 in 5 year storm event). Council received more than 130 stormwater and flood-related requests following that event.

The local community have documented the impacts of recent weather events that have impacted Evan Jones Park and the adjacent Whites Creek Lane, including this event in February. Community members have reported extensive overland flows through Evan Jones Park into the lane, together with impacts to the playground and gross pollutant trap (GPT) within the park, causing dangerous hazards.

At the Council meeting held on 11 March 2025, Council resolved the following:

1. That Council develop a plan for safe and effective flood management across Evan Jones Playground and Whites Creek Lane, Leichhardt and upgrades to the infrastructure in this playground and street, including:

a) reviewing and reporting on the timeline for the implementation of any relevant recommendations of the Leichhardt Flood Risk Management Plan which applies to flood management in this area;

b) undertake investigations of all components of the stormwater drainage system which drains from Emma Street to the Whites Creek Channel through Evan Jones Park, in collaboration with Sydney Water;

c) ensuring that stormwater improvements are included as part of the playground upgrade for Evan Jones Playground planned in FY2025/2026, including the replacement of bark chips in the playground with a surface that does not clog local drains;

d) clearing and preparing a maintenance plan for the stormwater drains in Whites Creek Lane, in collaboration with Sydney Water where necessary;

e) reviewing the street sweeping schedule for the lane and advising Whites Creek Lane residents via letterbox drop of the schedule;

f) Council officers to hold a public meeting with residents to publicly discuss and assess the grove of trees in the reserve land on the corner of Whites Creek Lane and Styles Street for any danger and soft soil as the result of recent heavy rains; and

g) reviewing and improving the dead-end signage at the entrance to Whites Creek Lane at Reserve Street.

2. That Council report this plan to the May 2025 Council meeting, in time to inform the budget.

A report was subsequently presented to the 20 May 2025 Council Meeting. The discussion below includes the details regarding the Leichhardt Flood Risk Management Plan, the Sydney Water drainage system within Whites Creek and Evan Jones Park, and recurrent maintenance of the stormwater system and laneway.

DISCUSSION

Evan Jones Park is located at the confluence of two significant trunk drainage systems, being Whites Creek, which is located along Whites Creek Lane, and one of its tributaries which extends up to Balmain Road in Leichhardt. Both these drainage systems are owned and managed by Sydney Water.

Whites Creek was channelised between 1898 and 1935, replacing the natural creek line as development progressed through Leichhardt and Annandale. The channelised creek takes the form of an underground culvert between Parramatta Road and Moore Street, upon which it becomes an open channel through Whites Creek Valley Park and beyond to Rozelle Bay.

Gross pollutant traps (GPTs) have been constructed to collect litter, silt and debris from these trunk drainage lines, with both located in Evan Jones Park. Sydney Water owns and cleans the GPT connected to the Whites Creek Channel, whilst Council is responsible for the GPT near the Evan Jones Playground which services the tributary.

a) Leichhardt Flood Risk Management Plan

Council adopted the Leichhardt Flood Risk Management Study and Plan (FRMSP) in 2018, which included mitigation options to address the risk of flooding across all catchments in the former Leichhardt Local Government Area, including this area of Whites Creek.

The Leichhardt FRMSP identifies the following potential flood mitigation options for this area:

· Upgrade of the Whites Creek stormwater channel, which is largely located within Whites Creek Lane, but extends from Rozelle Bay to Norton Street and upstream of Parramatta Road.

· Upgrade of the stormwater pipeline which extends from Whites Creek Lane to Balmain Road.

Although these trunk drainage lines are owned by Sydney Water, previous discussions with their representatives have indicated that the costs associated with any upgrade or amplification of these pipelines would need to be funded by Council. The combined cost for the above works was estimated in 2017 to be approximately $35 million, which is a prohibitive for Council to fund alone.

While Council does seek additional funds through state and federal grants to support these types of major upgrades, due to the limited funding available through these grant programs and the increasing level of detailed design required to support such a grant, it is likely that such works would be beyond the capacity of Council to deliver in the short to medium term without significant impact on other Council services.

Therefore, the current primary management actions to manage and mitigate the impact of flooding are therefore primarily dependent on non-structural measures such as planning controls (raising houses and garages above flood levels), emergency response planning (evacuation routes and education) and inspection and maintenance of stormwater assets (video survey of pipelines and cleaning where required).

It must be noted that any upgrade of Whites Creek and its surrounds would not remove flooding in its entirety through the former creek line and that these non-structural measures would still need to be kept in place regardless of the delivery of any stormwater upgrade.

b) Drainage system from Emma Street

The trunk drainage line between Emma Street and Whites Creek Lane extends as far north as Balmain Road. This drainage line is owned and maintained by Sydney Water.

Sydney Water advise that they undertake yearly condition assessments of their stormwater pipelines. Council has requested that they undertake a CCTV inspection of this line in light of the recent flooding event.

c) Drainage maintenance

Maintenance and cleaning of all Council GPTs is conducted on a quarterly schedule, with the Evan Jones GPT serviced in December 2024, then again in March 2025 following the storm event.

The most recent service indicated that the unit was operating as expected, with a volume of collected materials consistent with previous cleans. However, it was identified that the lids of the GPT had missing or damaged bolts which have been repaired/replaced.

A specialist consultant has also been arranged to conduct a comprehensive audit of the GPT in the next four weeks to confirm the unit is operating effectively and whether any improvements are necessary.

As above, Council staff have requested that Sydney Water undertake an inspection of their drainage pipeline to ensure that it is operating at full capacity.

Staff are also in discussions with Sydney Water to review our maintenance scheduling and processes to identify whether there is an opportunity for both organisations to collaborate to improve our respective maintenance services for the community.

d) Street sweeping

Whites Creek Laneway is currently serviced on Council’s endorsed 40 working day cleaning program for residential streets and laneways across the LGA. Council operations teams will continue to monitor this site and assess the need for an increase in service. White’s Creek Lane is next due to be serviced in May as per the current program. This service will include weed removal, collection of dumped rubbish, gutter cleaning, and debris removal. Council operations teams will letterbox drop the surrounding properties notifying them of the current service levels, the last service date and the next proposed service date as per the current service program.

e) Trees on corner of Styles Street and Whites Creek Lane

Council’s Public Tree team will lead a meeting on site to discuss any tree matters across the site. Council’s engagement and Public Tree team will work with the community to finalise a meeting date and time which is expected to be in the first week of June.

f) Street signage

The intersection of Whites Creek Lane and Reserve Street has been reviewed by the Traffic and Transport Planning team who advise that both approaches have sufficient signage indicating that the road (Whites Creek Lane) is a ‘No Through Road’ north of Reserve Street. However, the signage will be repositioned to improve visibility.

Council considered the above matters at the 20 May 2025 Council Meeting and resolved:

1. That Council receive and note the report.

2. That Council write to Sydney Water requesting updated costing associated with upgrading of the Whites Creek stormwater channel.

3. That Council identify grant funding options available, and preparatory work that would be needed to apply for such grants, to fund these upgrades.

4. That Council report the outcomes of these engagements to Council in August 2025.

Items 2, 3 and 4 are currently being actioned.

FINANCIAL IMPLICATIONS

An amount of $150,000 has been included in the draft budget for the 2026/27 financial year for the upgrade of the Evan Jones Playground.

Maintenance undertaken to date, including installation of timber edging in the park and cleaning of the Evan Jones GPT, was funded through existing operational budgets.

ATTACHMENTS

Nil.

Flood Management Advisory Committee Meeting

28 May 2025

Item No: FMACC0525(1) Item 4

Subject: Public Forum to the Flood Management Advisory Committee

Prepared By: James Ogg - Stormwater and Asset Planning Coordinator

Authorised By: Manod Wickramasinghe - Acting Director Engineering

RECOMMENDATION

1. That Flood Management Advisory Committee receive and note the report.

2. That a revised Terms of Reference including details of the Public Forum is provided to the Flood Management Advisory Committee in August following a review by Council’s Governance team.

STRATEGIC OBJECTIVE

This report supports the following strategic directions contained within Council’s Community Strategic Plan:

5: Progressive, responsive and effective civic leadership

EXECUTIVE SUMMARY

The Inner West Flood Management Advisory Committee was first established in 2017 in accordance with the Floodplain Development Manual (2005).

The committee is advisory in nature and does not have or exercise any formal powers of Council. The committee is established by Council and reports its recommendations to Council via a report and publication of its minutes. Any resulting actions ultimately require the approval of Council.

This report reviews the purpose of the Flood Management Advisory Committee, compares the operation and procedures of the Local Traffic Committee and makes suggestions for implementation of a public forum for the Flood Management Advisory Committee, ahead of formal recommendations at a later meeting.

BACKGROUND

The Inner West Flood Management Advisory Committee (FMAC) was first established in 2017 in accordance with the Floodplain Development Manual (2005) – since superseded by the Flood Risk Management Manual (2023) (the Manual).

The FMAC is established by Council to support and oversee the flood risk management process in accordance with the guidance of the Manual.

At its meeting on 12 November 2024 (C1124(1) Item 26), Council resolved:

6. That Council provide for members of the public to present to the Flood Risk and Management Committee on flood related matters by establishing a public forum, as is the case with the Inner West Council Traffic Committee.

DISCUSSION

Under the guidance of the Manual, the main objective of a Flood Management Advisory Committee is to assist councils in undertaking flood studies and developing Flood Risk Management Plans for a given study area, including advice on priorities for implementation. The committee primarily acts as a forum to discuss technical, social, economic, environmental and cultural issues and distil these viewpoints into the final Flood Studies and Flood Risk Management Plans adopted by the Council.

The committee is advisory in nature and does not have or exercise any formal powers of Council. The FMAC reports to the Council through the reporting of its minutes, with any recommendations requiring the approval of Council, which has the final decision-making authority.

It is similar to, though not directly comparable with, Council’s Local Traffic Committee (LTC). Like the Flood Management Advisory Committee, the Local Traffic Committee is advisory in nature with no decision-making powers. The LTC is primarily a technical review committee designed to consider the technical merits of proposals, ensuring that any proposal meets current technical guidelines, prior to being approved by Council.

Current Operation of the Local Traffic Committee

The LTC is primarily a technical review committee, made up of representatives of Council, NSW Police, Transport for NSW and the local State MP. The LTC is designed to consider the technical merits of proposals, ensuring that any proposal meets current technical guidelines, prior to being approved by Council. The merits of the scheme, from a public perspective, is the responsibility of the Council and thus residents’ views should be taken into account by the Council rather than the LTC.

Noting this, public participation in the LTC operates on an invitational basis. Residents and other stakeholders are notified when a specific report is to be tabled at the LTC relating to their immediate area or an item that they have previously been consulted on or made a submission to.

Reports to the Committee are typically prepared following completion of an investigation into requested parking or traffic management changes, exhibition of a Local Area Traffic Management Plan, or the detailed design of structures that might change road shape or performance (such as a raised pedestrian crossing).

Those interested in making a submission to the committee are required to register their intention by the close of business the day before the meeting is held.

Considerations for a Flood Management Advisory Committee Public Forum

As noted above, the main objective of a FMAC is to assist the council in undertaking flood studies and develop a Flood Risk Management Plan for a given study area, including advice on priorities for implementation.

The ongoing input and engagement of residents, businesses and community groups is important to this process of ongoing oversight and review. The design of a public forum process should aim to improve the Committee and Council’s understanding of matters under consideration to achieve better decision-making outcomes.

With these in mind, the following measures are put forward to the FMAC for consideration:

Reports to the committee:

- Progress reports and consultation reports during the preparation of a Flood Study or Flood Risk Management Plan will continue to be presented to the FMAC in accordance with the guidance of the Flood Risk Management Manual.

- It is proposed that a standing item be included within the meeting agenda where staff report on requests related to substantial flooding of a street or building, and the outcome (not including drainage or minor nuisance flooding within a street, such as might be caused by gutter damage or minor stormwater overflows).

- A location that receives multiple requests from separate addresses may trigger a report to be presented to the committee

- An investigation that proposes new flood mitigation works would be presented to the committee for review

- The committee can resolve that an investigation be undertaken into a specific location or issue, and a report provided at a following committee meeting.

Submissions:

- Where a request has resulted in proposed capital works, the resident is informed of this and advised of the next meeting of the FMAC where this will be presented

- Where multiple requests have triggered a report to the FMAC, all those who submitted a request will advised of the next meeting of the FMAC where this will be presented

- Any member of the public requesting to speak to an item at the meeting is required to register their intent prior to the meeting to receive an invitation to the online meeting

- Submissions are to be made at the start of a meeting for the consideration of members during the remainder of the meeting

- Submissions are to be limited to three minutes in accordance with the Council’s Code of Meeting Practice.

Note that detailed design undergoes a separate community engagement and submissions are managed within this process

Following the feedback of the committee Council officers will undertake a review of procedures with the support of Council’s Governance team and provide an updated Terms of Reference to the August committee meeting for endorsement.

FINANCIAL IMPLICATIONS

There are no financial implications associated with the implementation of the proposed recommendations outlined in the report.

ATTACHMENTS

Nil.