Flood Studies

Flood Prone Land Policy

Under the NSW Flood Prone Land Policy the management of flood prone land is, primarily, the responsibility of councils. The primary objective of the policy is to reduce the impact of flooding and flood liability on individual owners and occupiers of flood prone property, and to reduce private and public losses resulting from floods, utilising ecologically positive methods wherever possible. That is:

  • A merit approach shall be adopted for all development decisions in the floodplain
  • To take into account social, economic and ecological factors, as well as flooding considerations;
  • Both mainstream and overland flooding shall be addressed, using the merit approach, in preparation and implementation by councils of strategically generated floodplain risk management plans;
  • The impact of flooding and flood liability on existing developed areas identified in floodplain risk management plans shall be reduced by flood mitigation works and measures, including on-going emergency management measures, the raising of houses where appropriate and by development controls; and
  • The potential for flood losses in all areas proposed for development or redevelopment shall be contained by the application of ecologically sensitive planning and development controls.

Council is currently developing flood studies and floodplain risk management studies in accordance with the Flood Prone Land Policy and the Floodplain Development Manual.

Bowral Floodplain Risk Management Study & Plan

Wingecarribee Shire Council engaged Bewsher Consulting Pty Ltd to prepare a Flood Study and a Floodplain Risk Management Study & Plan for two catchments in Bowral: the Mittagong Creek catchment and the “Beavan Place” sub-catchment.

The Mittagong Creek catchment starts to the west of Old South Road, runs under a number of Bowral streets, passes under the railway near the Swimming Centre and travels along the western side of the railway past the Sewerage Treatment Plant before joining the Wingecarribee River. 

The study assessed various potential floods and developed plans to mitigate the effects of flooding in Bowral.

The study was completed in 2009 and was adopted by Council.

The flooding information about Bowral floodplain can be found in the following links:

Burradoo BU2 Catchment Flood Study & Plan

Wingecarribee Shire Council engaged Cardno Lawson Treolar Engineering Consultants to undertake a flood study of the Burradoo Catchment BU2.

The catchment covers an area of 244 hectares and stretches from the ridgeline to the west of Eridge Park Road, centring on the intersection of Moss Vale Road and Holy Road; it then crosses Burradoo Road near the Yean Street intersection before outletting under the railway just north of Burradoo Station to join Mittagong Creek.

The study assessed potential flood behaviour in the catchment. The flood study was the first step towards the overall Floodplain Risk Management process in accordance with the NSW Floodplain Development Manual. The flood study was completed and adopted by Council in 2011. The Floodplain Risk Management Study for the Burradoo catchment BU2 is in progress and is expected to be complete in 2013.

The flooding information for the catchment can be accessed through the following links:

Gibbergunya Creek Flood Study

In 2002 Wingecarribee Shire Council engaged Catchment Simulation Solutions, consulting engineers, to undertake a flood study for the Gibbergunyah Creek catchment.

The Gibbergunyah Creek catchment occupies a total area of 10.5 km2. The creek originates in the vicinity of Mount Gibraltar and drains in a northerly direction through the Mittagong urban area, where it is joined by the Chinaman’s Creek and the Iron Mines Creek and eventually joins the Nattai River.

The study assessed potential flood behaviour in the catchment. The flood study is the first step towards the overall floodplain risk management process in accordance with the NSW Floodplain Development Manual 2005. The flood study was completed in August 2013 and subsequently adopted by Council in September 2013.

Maps

The following maps provide details of the study as described.

AEP = Annual Exceedence Probability

ARI = Annual Recurrence Interval

Nattai River Flood Study

Wingecarribee Shire Council recently engaged consulting engineers Catchment Simulation Solutions to undertake a flood study for the Nattai River catchment.

The Nattai River catchment occupies a total area of 6.75 square kilometres. The Nattai River Flood Study is the first step towards preparing a Floodplain Risk Management Study and Plan for the catchment.

The flood study was completed in early 2014 and subsequently adopted by Council in March 2014.

Flood Map Attachments

1. Catchment plan

2. 1% AEP (100 year ARI) Flood Risk Precincts Maps

3. 1% AEP Depths & Velocities Maps

Nattai Ponds Catchment Floodplain Risk Management Study & Plan

The Nattai Ponds Catchment Floodplain Risk Management Study and Plan was completed in 2019 and the final report was adopted by Council on 12 February 2020.

The study report can be accessed via the following links:

Nattai River Floodplain Risk Management Study & Plan

Council appointed WMA Water Pty Ltd to undertake a floodplain risk management study & plan for the Nattai River Catchment in Mittagong.

The study was completed in 2016 and was adopted by Council in April 2017. 

Whites Creek Flood Studies & Plans

Review of the Whites Creek Floodplain Risk Management Study and Plan

The Review of the Whites Creek Floodplain Risk Management Study and Plan was completed in 2020 and the study report was adopted by Council on 24 June 2020.

Please use the following links to access the report:

Wingecarribee River Flood Study

Wingecarribee Shire Council recently engaged consulting engineers Snowy Mountains Engineering Corporation (SMEC) to undertake a flood study for the Wingecarribee River catchment.

The Wingecarribee River catchment occupies a total area of 225 square kilometres. The flood study covers the area upstream of the Wingecarribee Dam to Wallaby Rocks in Berrima.

The study assessed potential flood behaviour in the catchment.

The flood study is the first step towards the overall floodplain risk management process prescribed by the NSW Floodplain Development Manual 2005.

The flood study was completed in February 2014 and subsequently adopted by Council in March 2014.

The attached Web Upload document contains the following maps:

1. Catchment plan

2. 1% AEP (100 year ARI) Flood Depths

3. 1% AEP Provisional Hydraulic Hazard Maps

4. 1% AEP Flood Depths-Berrima

5. 1% AEP Flood Depths- Burradoo

Nattai Ponds Flood Study

Council appointed Catchment Simulation Solutions to undertake a flood study for the Nattai Ponds catchment. The flood study was completed in 2016 and was adopted by Council on 12 October 2016.

The information can be downloaded by clicking on the following files:

Wembley Road and Farnborough Drive Catchments Overland Flow Study

Wembley Road and Farnborough Drive Catchments Overland Flow Study

Council appointed Catchment Simulation Solutions Pty Ltd to undertake an overland flow study for the Wembley Road and Farnborough Drive Catchments in Moss Vale. The Overland Flow Study was completed in August 2017 and was adopted by Council on 13 September 2017.

The study report can be downloaded by clicking on the following link:

Robertson Village Overland Flow Study

Council commissioned J Wyndham Prince to undertake an overland flow study for Robertson Village. The flood study was completed in 2016 and was adopted by Council on 14 June 2017.

The study report can be downloaded by using the following links:

Gibbergunyah Creek Floodplain Risk Management Study & Draft Plan

The Gibbergunyah Creek Floodplain Risk Management Study & Plan was completed in early 2016 and the study report was adopted by Council in July 2016.