Flood Impact Emerald District Fitzroy Flood Forum, Wednesday 6 August 2008 Bill Wilkinson Environmental Recovery Program Leader Seconded from Natural Resources and Water About this talk The Event Key Streams that Flooded Impact Response Key Issues Lessons Learned Before the Event Recovering from citrus canker Mini tornado Sept 07 Last flood of any consequence Policemans Creek - Rubyvale 2004 Nogoa River - Emerald 1990 Fairbairn dam 36% capacity. Then the Rain Very heavy rainfall 16 th to 20 th January. Headwaters of creeks along Drummond. 700mm at Bogantungan (>1:2000 ARI) 650mm at Jo Jo Station 520mm at Anakie (1: ARI) 500 mm at Peakvale (1:2000 ARI) (Note: These are rainfall probabilities - not flood return frequencies) Rain amount and intensity decreased going east, north east and south east. Key Streams Theresa / Carbine Retreat / Centre Blackboy / Woodbine Medway / Ducabrook Echo / Joe Joe Flood affects large area.. Sapphire Source: Dartmouth University, NRW and CHRC mapping Central Highlands Regional Council Flood Peaks A subsection of the Nogoa Catchment :00am :00am :00am :00pm :00am :00pm :00am :00pm Inundation 300,000ha - Belyando / Suttor 270,000ha - Nogoa / Comet Fairbairn Dam Reached 4.4m over spillway, 158.3% capacity Peak inflow into dam 6200 m 3 sec total inflow 2,388,860 ML Peak outflow 2990 m 3 sec total outflow 1,555,960 ML The rate and rise of creeks took many people by surprise. Relativity to Previous Events Nogoa River (Vince Lester Bridge) m m m m m m Jan m Theresa Creek (Gregory Highway) m Jan m Gemfields Retreat Creek - ???? No hard data. Policemans Creek - Smaller then 2004 event Fairbairn Dam completed 1972 Impacts Direct and indirect Tangible and intangible Some areas inundated for weeks Others less then 24 hours Recovery is a long process Transport.. Gregory Highway Grasstree Creek Homes.. Retail.. Cropping Spring Sorghum Before Spring Sorghum After Grazing Mining / Industrial.. Sport & Rec Cricket Grounds Became Ski Grounds Golf became Mini Golf - 1 hole, plenty of water traps Managing Sightseers became a Full Time Job Impacts 3,160 residents registered for evacuation. 166 homes, 73 units and 10 uncompleted buildings seriously damaged. 80 homes with minor water damage. Damage to 10 industrial sheds, 1 shopping centre, 1 day care centre,1 big box retail and 1 not-for- profit agency. Increase in Ross River Fever and Barmah virus Impacts Local Business : Cleanup and repairs, Re-establishment, Relocation Depleted, Stressed, Tired workforce 30-70% downturn in turnover Transport operators severely constrained by road restrictions Smaller communities buy out of food and fuel Impacts Irrigation 6 properties - total damage >$1million 10 properties between $250K and $1 million Grazing Generally 20 40km of major fence repair Road and water storage repairs Stock displacement and loss (high in Belyando) Pasture death and weed incursion. Impacts Coal Mining Sector Roughly, we estimate the industry lost between $1.5-2 billion worth of production as a consequence of heavy rainfall and flooding that extended from Sonoma (Collinsville in the north) to Jeebroopilly (near Amberley). Qld Resources Council Pasture, Weeds.. Up to 95% buffel death if inundated >7 days Yield decline kg to 300kgha Slow recruitment of desirable species Incursion of Parthenium, Nogoora Burr, Parkinsonia, Harissia CactusHymanachne?? Native grasses on lighter country OK Response Shire Council established the Central Highlands Community Recovery Group (see Kerrys talk) Approach very successful, a good model High level of co-operation between Agencies, Industry, Private Sector and Community Dedicated Recovery Team Economic recovery Infrastructure recovery Environmental recovery Social recovery Key Issues Flood warning and communications. Quantifying damage & recovery needs accurately. Measuring flood behaviour, timing and water levels. Coordination of aerial / imagery capture. Emergency rescue resources. Insurance and building repair timeframes. Roads and transport. The flood was big affected a large area, significant cost to many individuals / businesses Some Positive Outcomes Flood mapping and review of modelling Review of flood warning instruments & communications Radar station Community engagement and feedback process Increase in SES volunteer numbers Ongoing commitment by Council, Agencies and sectors to complete tasks and tools that will assist future flood preparedness Flood Inundation Mapping Detailed inundation maps Fairbairn Dam to Emerald township High Tide Line Only approx 350km Nogoa Floodplain Nogoa at Rutland Retreat Creek at Sapphire Portion of Policemans Creek Other streams where not done because of time and previous floods were larger A number of high water elevations in AHDm Nogoa Floodplain Dam to Comet Around Sapphire Stream cross sections and gradients in critical areas All this data did not exist before. It has been provided to modellers. Not All Under Water At Same Time The maps do not represent an instantaneous point in time. The peak water level changes, as water moves down the catchment. Each map represents the highest flood points that occurred over the duration of the whole event. Some Lessons Many of us live on the floodplain we have forgotten flood cycles given the last years of drought cycles. Integrity of civil infrastructure levees, design and construction standards. Catchment flood prediction models were very close to what occurred. Communications need attention. Need to improve some gauging station gaps, communications and warnings out, and business and community preparedness. Lessons Learned ctd Maps, data and disaster management tools be exchanged before next flood with emergency response groups. State / local government standardise a radio TV tune like the Cyclone warning for on the hour, every hour Responsibility for flood warning and response, cant rest with one or two organisations - requires broader partnerships, commitment and sharing skills and knowledge, established upfront. Central Highlands Regional Council approach is an example of how things can and should work. 15.78m (Nov 1950) 15.36m (Jan 2008) 12.97m (Feb 1978) Maybe Flood cycle has returned m (Feb 1984) Often have repeat floods in the same period eg. 1950, 1955, 1956, 1963