IntroductionWollongong is a coastal city of around 180,000 people located approximately 80 kilometres south of Sydney. It is bounded by a steep escarpment to the west forming a coastal strip ranging in width from less than a kilometre wide in the north to around 20 in the south.
There are a number of small streams that cut through the network of streets and back yards of many of the homes along this coastal strip and they vary from slow shallow water channels to dry small ravines that are overgrown with vegetation. There are also a few Coal Mines, with their stock piles of coal and sludge ponds dotted along the upper reaches of the escarpment.
On Monday 17th August, intense rainfall caused major flash flooding to the city and the suburbs. A number of rainfall stations recorded more than 300mm and some more than 400mm in a 3-hour period during the evening of the 17th.
The EventOn the Monday rain had been falling for some time along the Illawarra escarpment and the ground had soaked up a considerable amount of water. It was not long, therefore, before the run off from the land was starting to affect the streams, waterways and the storm water systems.
By around 1800 hrs the rain intensity increased, with torrential rain falling in concentrated areas. Within a short time water that was lapping at the bottom of yards was now gushing through houses, meters deep. The once quiet suburban streets now became fast flowing rivers; the current that flowed was washing everything away including, people, cars, animals, BBQ gas bottles, fuel and other hazardous substances. Houses were being moved off their foundations. Once secure road bridges were moved due to the build up of debris that was blocking the flow.
People that were at home were unable to cope with the intensity of the rain and the storm water caused by it; people were now being swept off their feet and into dangerous situations. The intensity and resulting damage was too much for one agency to handle, so before long the State Emergency Service, Police, Fire Brigade and the general public were conducting heroic rescues. Vehicles were being washed off roads by storm waters, people that had tried to travel Bulli Pass found themselves trapped in vehicles by avalanches, boulders that were as big as cars started to roll down the road towards the vehicles.
This had now become a highly dangerous situation, with the onset of darkness, fast flowing water and Mother Nature at her worst. This was going to be one hell of an event.
The ResponseThe Wollongong City SES unit went active late on the Monday morning following a couple of minor requests for assistance due to leaking roofs etc. A rescue team was activated by the Duty Officer who controlled the situation from the headquarters for a couple of hours. By mid afternoon calls had started coming in a bit more quickly so operations staff were called in who then controlled the SES involvement for the remainer of the event. A second rescue team was also activated. Water was building up in the low lying southern suburbs of the city, and as a few roads had already been closed a flood rescue boat crew was called in and placed on stand-by.
With the onset of darkness the situation had started to get hectic. An additional response vehicle was hired to enhance our fleet of rescue vehicles to 4. Our Local Emergency Management Officer (LEMO) as well as senior representatives from the other Emergency services had started to arrive at our headquarters. We requested that our neighbouring units, both Kiama and Shellharbour would come to assist us as they had little or no requests for assistance in their areas. The focus of the operation had now shifted from protecting property to the rescue of trapped persons with the possibility of them being washed out of their homes or being washed away in their vehicles.
Between 2000 hrs and 2100 hrs the peak of the storm hit. At this time our own Headquarters was being threatened by rising waters and the possibility of our own personnel being washed away as they attempted to save their own vehicles from two creeks (rivers now) at both ends of our street. (This was a race against time as many of our own personal vehicles now fell victim to the flood).
Our phone system had now failed and was reduced to 2 manual phones which were constantly busy due to the volume of urgent calls for assistance being received. The Triple-0 system was also overloaded and the fax was spitting out a constant stream of urgent requests that were being forwarded from Police Radio. Many calls for assistance also went to the Illawarra Division and State Headquarters of the SES which are located in Wollongong, and both of these offices were overloaded.
The EOC personnel were relocated by 4WD due to our SES HQ being inundated by water. This proved pointless, as they were soon needed to be rescued by our flood boat - the vehicle used initially became a flood victim. The boat was then needed to rescue persons from houses in the street as water was now flowing dangerously fast around and through the homes.
Police vehicles that had responded to calls for assistance were now calling for assistance themselves, as their own cars were being forced off the road by storm waters. Police Rescue and general duties officers were responding to people trapped on roofs and in houses as well as responding to looting that was going on.
Unfortunately there was a fatality due to the rapid rise of floodwater that caused a person to be trapped in their vehicle. In the same incident a taxi driver nearly lost his life as the taxi he was driving was swept into the raging waters. He was lucky to escape with his life only to see the headlights of his vehicle vanish as the water sucked it down to the bottom. It was eventually recovered with the aid of an excavator 5 days later.
Many vehicles were washed into the raging waters and tossed around like pebbles, wedged under bridges, stacked one on top of each other. We were unable to determine if there was any person trapped in the vehicles that we could see, so ropes and PFD's were fitted to rescuers and the vehicles searched.
With the intensity of the storm and the volume of rain tonnes of black sludge steam-rolled it's way down the mountain, taking with it anything that stood in its way. Whole streets and blocks of houses were inundated with this black substance. Houses were completely awash - up to a meter to two of this was in every room and every house within its path.
The Clean-upThe next day cars and debris alike littered the area, including highly volatile fuel and LPG containers, fire extinguishers and even bathtubs - if it wasn't nailed down then it ended up on the beach or out to sea. Even a VW Kombi van belonging to a local VRA member had been picked up and washed out to sea.
The EOC was established in the city and had taken control. On SES advice they divided the Wollongong local government area into 5 sectors. SES was given 2, Rural Fire Service 2 and the NSW Fire Brigade 1. Out of area SES units had began arriving from Sydney and the Southern Highlands in the early hours of the morning. At first light a street by street reconnaissance had begun with only assistance being given to life threatening situations and others tasked accordingly. By mid day all SES teams were deployed into the badly affected areas and designated to assist with anything that needed to be done in that area. Any calls that were received by any agency were given to the agency responsible for those sectors.
The SES was coordinating teams with shovels, bob cats, front-end loaders and bulldozers working to clean up and search for missing persons. The intensity of the water and coal moved foundations and cracked walls of houses to the extent of the possibility of collapse. Our teams cordoned off most of these sites and set to work jacking up the houses effected and stabilising with cribbing blocks and shoring up damaged walls with shoring techniques learnt over many years of Disaster Rescue training by our organisation. (Something that is starting to be referred to as USAR by other agencies).
Our unit continued to perform reconnaissance with the assistance of the SES State Training Team. These people who are trained in all aspects of rescue and were able to offer assistance, advice & suggest solutions to the many problems that faced us. They also have the same appointed role as Senior Emergency Officers and Emergency Officers. This was an added bonus as they were able to assist the other agencies as to our combat roll.
The routine for the remainder of the event consisted of tasking from first light through to just after dark. The activities varied from assisting householders with the removal of damaged property and furniture to the clean up the inside of the homes. Calls were still coming in for assistance to shore and stabilise homes that were still moving.
We kept a rescue team on stand-by at our headquarters throughout each night when the other rescue crews had stood down for welfare and rest. This team was used to respond to urgent calls for assistance that came in during the night. This included a number of landslips along the escarpment that threatened anything from a few residential homes to a whole village. These involved our team performing an initial reconnaissance, then assessment by a geotechnical engineer who recommended evacuations in a couple of the cases which we then carried out with the assistance of the Police.
Early on the Friday evening, control of the event was handed back to the local SES unit after 4 days and the EOC closed down. We were still utilising out of area teams up until the last day on Saturday 22nd to finish the clean up. Due to the fatigue and the non-urgent nature of the remaining assistance required, our headquarters closed down on Saturday night then reactivated on the Monday morning with members of our unit transporting and supervising a paid clean up labour force to carry out the remaining work such as hosing and loading debris into garbage trucks. This continued for most of the second week, at which time it was considered that our involvement was at an end.
SummaryIn closing this article, a final comment must be to highlight the assistance given to the city of Wollongong by the unpaid volunteers of the State Emergency Service and the Rural Fire Service, particularly those from outside Wollongong. Without these organisations and their dedication the cost of this incident would have been much higher.