Flood management

flood risk management

Middle Harbour northern catchments

Council is calling on residents and business owners to share their ideas to improve flood management in the Middle Harbour northern catchments.

The catchment area includes Middle Harbour Creek (and associated tributaries) in St Ives and Rocky Creek (including Stoney Creek and High Ridge Creek) in Gordon/East Killara which flow into Middle Harbour.

This flood study commenced in 2020 and the project team is now seeking feedback from the community. A letter and information leaflet will be mailed to residents in the catchment area.

The public are also invited to complete a survey.

Complete the survey here

More information

For more information about this study please read the community newsletter(PDF, 2MB).

Middle Harbour southern catchments

Council has received funding for the Middle Harbour southern catchments flood study through the NSW Office of Environment and Heritage Floodplain Management Program grants 2018–19.

The Middle Harbour Southern Catchments Flood Study area consists of five catchments. These include Echo Point and Moores Creek in Roseville, “Wellington Road” and Gordon Creek in Lindfield and “Northern and Southern Creeks” in Killara, all flowing into Middle Harbour.

Steep terrain and ridge-top development have led to major flood risk within Ku-ring-gai, from flash flooding along headwater streams and drainage depressions.

This flood study commenced in 2019 and has been completed.

More information

Flood Risk Management Committee

The Flood Risk Management Committee is an advisory committee of Council and its establishment is the first formal step in the floodplain risk management process.

The management committee acts as both a focus and forum for the discussion of technical, social, environmental, cultural and economic issues and for the distillation of possibly differing viewpoints on these issues during the development of the flood studies and flood risk management plans. Consequently, its membership is diverse and consists of representatives from Council (elected representatives and staff), relevant government agencies including Office of Environment and Heritage, National Parks and Wildlife Service NSW, Sydney Water and the State Emergency Service, as well as representatives from the local community.

Council’s Floodplain Risk Management Committee (established in 2015) is currently overseeing implementation of the floodplain risk management process for sub-catchments in the LGA, in partnership with the NSW Office of Environment and Heritage.

There are currently 5 community representatives on Ku-ring-gai’s Flood Risk Management Committee in addition to Chair Councillor Callum Clarke and Deputy Chair Councillor Donna Greenfield.

Meetings of the Committee are held as required. Meeting agendas and minutes are published on Council's website.

Completed studies, reports and mapping

Blackbutt Creek Catchment

Blackbutt Creek Flood Risk Management Study and Plan was completed in August 2016.

This report builds on the findings from the Blackbutt Creek Flood Study (2014) and outlines measures to mitigate flooding including land use planning, community awareness, flood warning and infrastructure changes and upgrades.

Blackbutt Creek Flood Risk Management Study Report(PDF, 445KB)

Preliminary Floodplain Management Measures(PDF, 3MB)

Floodplain Risk Management Plan and References(PDF, 50KB)

Appendix A Locality Plan, Pipe Network and Vulnerable Locations

Appendix A Locality Plan(PDF, 2MB)

Appendix A Pipe Network Capacity(PDF, 4MB)

Appendix A Vulnerable Locations(PDF, 2MB)

Appendix A Emergency Response Classification Maps

Appendix A AEP Emergency Response Classification Maps(PDF, 7MB)

Appendix A PMF Emergency Response Classification(PDF, 4MB)

Appendix A Flood Risk Precinct 20% & 5% AEP

Appendix A Flood Risk Precinct Maps 20% AEP Proposed True Hazard Classification(PDF, 5MB)

Appendix A Flood Risk Precinct Maps 5% AEP Proposed True Hazard Classification(PDF, 5MB)

Appendix A Flood Risk Precinct 1% and AEP

Appendix A Flood Risk Precinct Map 1% AEP Proposed True Hazard Classification(PDF, 5MB)

Appendix A Flood Risk Precinct Map PMF Proposed True Hazard Classification(PDF, 5MB)

Appendix A Flood Modification Options

Appendix A Flood Modification Mitigation Options(PDF, 5MB)

Appendix B Assessment of Changes in the Blackbutt Creek Catchment

Appendix B Assessment of Changes in the Blackbutt Creek Catchment(PDF, 3MB)

Appendix C Draft Flood Planning Matrix – Appendix D Sensitivity Memorandum

Appendix C Draft Flood Planning Matrix(PDF, 39KB)

Appendix D Sensitivity Memorandum(PDF, 189KB)

Appendix D Sensitivity Memorandum Map(PDF, 5MB)



Blackbutt Creek Flood Study

The Blackbutt Creek Flood Study is the first of a series of detailed flood studies to be undertaken in Ku-ring-gai. This study used historical information, landscape survey, stormwater pipe data and computer modelling techniques to indicate areas likely to be impacted by flooding. The original Flood Study was completed in December 2014.

Final Report Blackbutt Creek Flood Study – Appendix A – B Community Consultation Survey and Summary(PDF, 4MB)

Appendix C – Flood Depth Mapping(PDF, 10MB)

Appendix D Flood Level Mapping – Appendix E Summary of Peak Flows – Appendix F Hydraulic Categories Mapping(PDF, 9MB)

Appendix G Provisional Flood Hazard Mapping(PDF, 6MB)

Appendix H Flood Planning Area Mapping – Appendix I Preliminary Flood Emergency Response Classification of Communities – Appendix J Climate Change Impact Mapping(PDF, 5MB)

Lovers Jump Creek Flood Study Review Report

The Lovers Jump Creek Flood Study Review Report (2018) was adopted by Council in November 2018.

Lovers Jump Creek Flood Study Review Report 2018

Final Report(PDF, 2MB)

Appendix A - D(PDF, 5MB)

Appendix E - F(PDF, 3MB)

Appendix G - J(PDF, 6MB)

Appendix K - L(PDF, 3MB)