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Brisbane’s FloodSmart

Future Update 2016

Catchment FloodplainManagement Planning

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Brisbane’s FloodSmart Future

– Catchment FloodplainManagement Planning

Introduction

Brisbane is a thriving, world class city,enjoyed for its subtropical climate.During the summer months severestorms with heavy rainfall are commonand can result in flooding.

Managing and minimising the impactsof flooding have always been a priorityfor Brisbane City Council.

To ensure that Brisbane is betterprepared for flooding in the future andto address the recommendations madeby the Queensland Floods Commissionof Inquiry, Council developed theFlood Action Plan, establishing itscommitment to undertake catchmentfloodplain management planning.

This document outlines the catchmentfloodplain management planning,which has been undertaken to date fora number of Brisbane’s creeks.

Together we can build a moreresilient city; a city that is safe,confident and ready.

Contents

Introduction, page 2

FloodSmart Future Strategy2012-2031, page 3

Catchment floodplainmanagement planning, page 4

Catchment profiles, pages 5-15

Achievements in catchmentfloodplain management planning, page 16-17

Future floodplain managementplanning opportunities, page 18

What does Council do with theopportunities once they havebeen identified?, page 19

How you can Be Prepared, page 20

This document is:
  • a framework for planning and decision making
  • a strategic guide for Council, businesses and the general public
  • a suite of potential projects which could be implemented in the short mediumor long term.
This document does:
  • seek to reduce flood risk to people and the developed and natural environment
  • consider creek flooding and storm surge.
This document isn’t:
  • a statutory plan
  • detailed advice on specific locations or projects
  • a financial commitment to undertake every project.
This document doesn’t:
  • consider river flooding or overland flow.

River flooding will be considered as part of the Brisbane River Flood Studies being carried out by the Queensland Government. Council has a program of ongoing drainage investigation, design, upgrade and construction works which considers overland flow flooding.

FloodSmart Future Strategy 2012-2031

The Flood Action Plan also recognised the need for a long-termstrategic approach to flood risk management, and so theFloodSmart Future Strategy 2012-2031 was developed. Thestrategy aims to build a more resilient city; a city that is safe,confident and ready. The strategy outlines Council’s approachto flood risk management and forms an overarching approachto meet the challenge of managing flooding in Brisbane.This strategic approach to flood risk management is basedon gathering a comprehensive understanding of thebehaviour and consequences of flooding across a fullrange of flood events and then identifying an integratedsuite of measures to manage the risks.

Council is undertaking flood studies and floodplainmanagement planning for Brisbane’s creek catchments,to better understand flood behaviour and consequenceswithin our catchments. The flood studies provide the mostup-to-date technical information regarding flood behaviourincluding flood frequency, flow rate, depth, velocity, andextent. The information provided by the flood studies isthen used to understand the consequences of floodingand identify an integrated suite of floodplain managementmeasures through a process known as catchment floodplainmanagement planning.

Our vision is for communitieson floodplains that aresafebecause they understand theirlevel of flood risk and are takingaction to manage it.

Our vision is for growing ourcity and economy responsibly,confidentin how we adaptto flooding.

Our vision is for connected andengaged communities that arereadyfor flooding.

Catchment FloodplainManagement Planning

A catchment is an area of landsurrounded by natural featuressuch as hills, within which waterflows to a common low point,such as a creek, lake, river or bay.A floodplain is an area of land thatis subject to inundation by floods.Catchment floodplain managementinvolves assessing and managingflood risks within a catchment, orseries of catchments, to reduce theimpact on people and to property.

The FloodSmart Future Strategy usesfour tools for flood risk management:

1. flood mitigation infrastructure

2. flood awareness and information

3. land use planning anddevelopment control

4. flood emergency management.

Up until the 1970s, flood mitigationinfrastructure (e.g. dams, levees,channel modifications) was theprimary method of managing floodrisks in Australia.

A series of large floods in the 1970sresulted in a change of focus frommitigation infrastructure to land useplanning as a means of controllingdevelopments on floodplains. The1990s saw a focus on flood emergencymanagement and more recently therehas been an emphasis on providingflood awareness and information.

It is now recognised that best practicefloodplain management requires thecoordinated application of all of thesemanagement tools. Catchment floodplainmanagement planning makes useof these tools to identify a range ofmeasures to better manage flood riskwithin a catchment.

The process of catchment floodplainmanagement planning considers theconsequences of flooding on thecommunity, environment, businesses andinfrastructure. It aims to reduce the floodrisk to people and property, maintain localeconomic development and growth, ensureappropriate land use planning, protect thelocal environment and minimise impacts toinfrastructure and services.

By 2015, Council had completed a programof creek flood studies that provided thelatest creek flood data for more than 80%of urbanised areas across the city. Councilhas used this data to undertake catchmentfloodplain management planning for ourcreek catchments. The understanding offlood behaviour across the city and themanagement of Brisbane’s catchmentswill evolve as further information becomesavailable from Council’s ongoing programof flood studies.

Catchment Profiles

Brisbane is built around its waterways and all of Brisbane’s residents live within a catchment.

Some creeks start small, running through bushland high in the catchment, others flow acrossour suburbs and through parks. They crisscross our city until eventually flowing into Moreton Bay.

The following 10 catchment profiles will focus on a number of Brisbane’s creek catchments. They describe the size and location of the catchment, the history of flooding within the catchment,what we know about flooding in the catchment as well as some of the existing measures Council has in place to manage flooding.

There are some important points to note before you read on.

  • Some catchment profiles will include one catchment, while others include more than one. In some cases a number of the smaller catchments have been grouped together. For example, the Northern catchments are located to the north of Brisbane City and include some or all of
  • Albany Creek, South Pine River, Bald Hills Creek, Brighton Creek and Pine River floodplain.
  • There are a number of roads in many of the catchments that may become inundated during a flood – cars can be swept away from only a minor amount of fast flowing water. Roads which have at least a 50% chance of flooding in any given year are identified in the catchment profiles. Remember, if it’s flooded, forget it – never drive through or enter floodwaters.
  • Some catchments contain critical infrastructure routes – these are routes which are utilised foremergency access or evacuation during and following a natural disaster. Where these routes exist within a catchment, they have been identified in the catchment profiles.
  • The majority of creeks are made up of a number of tributaries. A tributary is a smaller stream or creek which flows into a larger creek.
  • Brisbane has 38 major creek catchments and 630 kilometres of waterways.
  • The combined catchment area of the creeks and rivers flowing into Moreton Bay is 21,220 square kilometres.

Breakfast/Enoggera CreekCatchment Profile

The Breakfast/Enoggera Creekcatchment covers an area of80 km2 and is located in thenorth-western suburbs ofBrisbane, starting in the BrisbaneState Forest in the D’AguilarRange and eventually joining theBrisbane River at Newstead.

The catchment contains four major creeks– Enoggera Creek, Breakfast Creek,Ithaca Creek and Fish Creek – whichflow through the suburbs of The Gap,Ashgrove, Bardon, Red Hill, Enoggera,

Paddington, Newmarket, Wilston,Windsor, Kelvin Grove, Herston,Spring Hill, Fortitude Valley, Albion,Lutwyche, Clayfield, and Bowen Hills.

The Breakfast/Enoggera Creekcatchment has a long history of significantflood events. Records indicate thatflooding has occurred in the catchment inFebruary 1931, June 1967, February and

April 1972, January 1974, April 1989,May 1996, May 2009 and January 2013.

To manage flooding in the catchment,the following floodplain managementmeasures have been implemented:

  • Enoggera Dam constructed in 1866and subsequent spillway works in1973 and 1976
  • two sections of Breakfast Creekstraightened in the lower reachesin 1931
  • in 2011, maintenance dredgingof the area of the creek betweenBowen Bridge Road and Kelvin Grove Road began
  • 20 properties purchased by Councilunder the Voluntary House PurchaseScheme since 2006
  • a Creek Flooding Alert Serviceestablished for the Herston andWindsor areas
  • four rainfall gauges and four streamlevel gauges installed to monitorthe rainfall and stream level heightsthroughout the catchment.

There are three criticalinfrastructure routes that traversethe Breakfast/Enoggera Creekcatchment: Bowen Bridge Road,Lutwyche Road and the Inner CityBypass.

The following roads located inthe Breakfast/Enoggera Creekcatchment have at least a 50%chance of flooding in any givenyear: Bowman Parade, CarwoolaStreet, Hilder Road, Quirk Street,Glenrosa Road, Gresham Streetand Kenwyn Road. Remember, ifit’s flooded, forget it – never drivethrough or enter floodwaters.

In the Breakfast/EnoggeraCreek catchment, there areapproximately 1000 buildingswhich have a 1% chance of beingaffected by creek flooding in anygiven year.

The waterway corridor alongwhich the creek flows hasgenerally been set aside asparkland and there are severalnatural assets within thecatchment including D’AguilarNational Park, Enoggera Reservoir,Mt Coot-tha Reserve, WaltonBridge Reserve, Banks StreetReserve, Woolcock Park, DowneyPark and Northey Street Markets.

Bulimba CreekCatchment Profile

The Bulimba Creek catchment isthe second largest of Brisbane’smajor creek systems with an areacovering 125 km2. The catchmentis located to the south of theBrisbane River and extends fromCalamvale in the south to Lyttonin the north.

It is bounded in the west by ridgesextending from Calamvale to Mt Gravattand Mt Gravatt to Cannon Hill andin the east by ridges extending fromRochedale South to Wynnum West.The highest point of the catchmentis Mt Gravatt. Flowing in a northerlydirection, Bulimba Creek dischargesdirectly into the Brisbane River about6.5 km upstream of Moreton Bay.

The catchment consists of eight majortributaries which include: Bulimba CreekEast, Bulimba Creek West, MimosaCreek, Spring Creek, Salvin Creek,Phillips Creek, Tingalpa Creek andLindum Creek.

Detailed records of flooding in Bulimbahave been collected since the 1960s andareas adjacent to the lower reaches ofBulimba Creek have suffered frequentflooding. Historically the largest floodto have occurred in Bulimba Creekin recent times was January 1974.Sections of the upper catchment wereheavily affected in the 2001 and 2004flood events. More recently, the lower

end of the catchment was affected bythe Brisbane River flood of 2011. Thesummer of 2013 saw two significantflood events within the catchment.

To manage flooding in the catchment,the following floodplain managementmeasures have been implemented:

  • Cleveland Rail bridge crossingupgraded in 1994
  • Mimosa Creek de-weeded in 2008
  • hydraulic structures such as the concrete channel near Bilan Street, Carina constructed in 1990\seven properties purchased by Council under the Voluntary House Purchase Scheme since 2006
  • a Creek Flooding Alert Service established for the Hemmant area
  • twelve rainfall gauges and three stream level gauges installed to monitor the rainfall and stream level heights throughout the catchment, with records extending from 1972.

In the Bulimba Creek catchmentapproximately 700 properties areat risk of a flood event that hasa 1% chance of occurring in anygiven year.

There are several significantnatural assets in the BulimbaCreek catchment which include

Wally Tate Park, Toohey Forest,Mt Gravatt Outlook Reserve,Belmont Hills Bushland Reserve,Whites Hill Bushland Reserve,Minnippi Parklands, Seven HillsReserve, Murarrie RecreationalGround and HemmantRecreation Reserve.

There is one critical infrastructureroute that lies within the BulimbaCreek catchment, the GatewayMotorway. Other interim criticalroutes within the catchmentinclude Belmont Road, ManlyRoad, Wondall Road andRandall Road.

Cabbage Tree CreekCatchment Profile

The Cabbage Tree Creekcatchment lies north of theBrisbane River and covers anarea of 45 km2 extending fromFerny Hills in the upper reachesof the catchment and joiningwith the mouth of Nundah Creekbefore flowing into Bramble Bayat Shorncliffe.

There are two main tributaries thatform the Cabbage Tree Creekcatchment; Cabbage Tree Creek andLittle Cabbage Tree Creek. There arealso several small tributaries includingCarseldine Channel, Taigum Channeland Gertrude Street Drain.

Cabbage Tree Creek and its tributariesflow through the Brisbane suburbs ofEverton Hills, Everton Park, Shorncliffe,Deagon, Sandgate, Taigum, Zillmere,Fitzgibbon, Boondall, Aspley, Carseldine,Bracken Ridge, Bridgeman Downsand McDowall.

The Cabbage Tree Creek catchmenthas experienced a number of historicflood events, including two events inJanuary 1974 and another event inFebruary 1992.

To manage flooding in the catchment,the following floodplain managementmeasures have been implemented:

  • regular channel maintenanceregime involving desilting upstreamand downstream of numeroushydraulic structures
  • weed management betweenBeckett Road and Lemke Roadincluding the removal of unwantedvegetation species and the plantingof native trees
  • three properties purchased by Councilunder the Voluntary Home PurchaseScheme since 2006
  • a Creek Flooding Alert Serviceestablished for the DeagonCreek area
  • six rainfall gauges and five streamlevel gauges installed to monitorthe rainfall and stream level heightsthroughout the catchment.

There are several natural assetswithin the catchment includingthe Boondall Wetlands, D’Aguilar

National Park, FitzgibbonParklands, Chermside Hills, CurlewPark, Bunyaville State Forest Park,Brisbane Entertainment Centreand the Mountain to Mangrovesnature trail.

In the Cabbage Tree Creekcatchment approximately 500properties have a 1% chance ofbeing affected by creek floodingin any given year.

There are two critical infrastructureroutes that lie within the CabbageTree Creek catchment: GympieRoad and the Gateway Motorway.Other interim critical infrastructureroutes within the catchmentinclude Old Northern Road.

Kedron BrookCatchment Profile

The Kedron Brook catchmentcovers over 110 km2 of land thatextends from D’Aguilar National

Park, downstream to the west ofthe Brisbane Airport at Nudgee,emptying into Moreton Bay

as the Schulz Canal. Smaller creeksthat flow into the brook along theway include Cedar Creek, SandyCreek and Cannery Creek.

The Kedron Brook catchment includes36 suburbs and a diverse mix ofresidential, commercial, industrial andcommunity areas with over 30 parksand reserves adjacent to the creek andits tributaries, with uses ranging fromconservation, open space, sports fieldsand golf courses.

Kedron Brook transforms from a naturalwaterway with large conservation areas,such as the Brisbane Forest Park to ahighly-structured waterway. Finally, at theGateway Motorway Deviation Bridge,the canal becomes the Kedron BrookFloodway – a wide-walled waterwayflowing to its outfall into Moreton Bay,near Nudgee Beach.

The Kedron Brook catchment containsmore than 130 km of bikeway whichhas been designed to provide a directconnection to the waterway. The bikewaycrosses Kedron Brook waterway at31 locations, making it susceptibleto flooding.

To manage flooding in the catchment,the following floodplain managementmeasures have been implemented:

  • engineered saltwater channelconstructed in the lower reaches ofKedron Brook
  • eighteen properties purchased byCouncil under the Voluntary HousePurchase Scheme since 2006
  • a Creek Flooding Alert Serviceestablished for the Cannery Creek andPound Creek areas
  • four rainfall gauges and five streamlevel gauges installed to monitorthe rainfall and stream level heightsthroughout the catchment.

In the Kedron Brook Catchmentapproximately 440 buildings are atrisk of a flood event that has a 1%chance occurring in any given year.

There are significant natural assetsin the catchment that are used bycommunity members like SparkesHill, Grinstead Park, Kalinga Park,Nudgee Waterholes Reserve andthe Boondall Wetlands.

Boondall Wetlands is aninternationally recognised habitatfor migratory wader birds inMoreton Bay.

There are a number of criticalinfrastructure routes that lie withinthe Kedron Brook catchment:Gympie Road, Lutwyche Road,Airport Link Tunnel, SouthernCross Way, East West ArterialRoad, Airport Drive and theGateway Motorway. Other interimcritical infrastructure routeswithin the catchment includeOld Northern Road, South PineRoad and Stafford Road.

Norman Creek and Perrin CreekCatchment Profile

The Norman Creek and PerrinCreek catchments cover acombined area of almost 40 km2.

The Norman Creek catchment islocated to the south-east of theBrisbane CBD and its many tributariesform an integral part of the Brisbanesuburbs of Annerley, Norman Park, EastBrisbane, Woolloongabba, Greenslopes,Coorparoo, Camp Hill, Holland Park,Holland Park West, Mount Gravatt andTarragindi. The Perrin Creek catchmentis located to the east of the BrisbaneCBD flowing through the suburbs ofMorningside, Cannon Hill and SevenHills before discharging to theBrisbane River.

Detailed records of flooding in NormanCreek have been collected since the1960’s; however more recently, floodinghas been experienced in February 2010,January 2011, February 2012, January2013 and twice during the summer of2013. Records indicate that the PerrinCreek catchment experienced floodingin January 1974, April 1988, February1992, May 1996 and January 2011.

To manage flooding in the catchments,the following floodplain managementmeasures have been implemented:

  • a number of waterway modificationprojects undertaken within the catchments, which include workssuch as channelisation, channelwidening, channel diversion andclearing of vegetation
  • two properties purchased by Councilunder the Voluntary House PurchaseScheme since 2006
  • fifteen rainfall gauges and five streamlevel gauges installed to monitorthe rainfall and stream level heightsthroughout the catchments, withrecords extending from 1974
  • a Creek Flooding Alert Serviceestablished for the suburbsof Coorparoo, East Brisbane,Greenslopes and Woolloongabba.

There are approximately 600properties in the Norman Creekcatchment and 50 properties in

the Perrin Creek catchment, whichare within an area that has a1% chance of being affectedby flooding in any given year.

There are a number of key habitatareas in the Norman Creekcatchment including the Toohey

Forest, Tarragindi Hill Reserve,Wellers Hill Reserve, StephensMountain and Thornycroft Street

Park. Perrin Creek is located withina highly urbanised catchment andthe Seven Hills Bushland Reserveis a popular ecological asset withinthe catchment.