Launceston was settled at the junction of three rivers - the North Esk, South Esk and Tamar Rivers. These are fed by a system of rivers and lakes that cover 14% of Tasmania.
Most of Invermay and some parts of Newstead sit within the flood plain, an area that will flood in a natural river system. In fact, Invermay's ground level is actually below the high tide, and if the flood levees were not in existence some parts of Invermay would be subject to water inundation twice a day with high tide.
Since Launceston's establishment, there have been 36 significant floods with 1929 reputedly the worst. However the years 1852, 1863 and 1893 are also recorded as very serious flood events.
The 1929 flood saw the evacuation of 4,000 people. 1,000 homes were inundated and 20 ultimately condemned. During the flood, 4,250 cumecs* of water flowed from the South Esk River and 567 cumecs flowed from the North Esk River, prompting authorities to seriously consider a new levee system.
Most recently in In June 2016, 2,375 cumecs of water from the South Esk River and approximately 800 cumecs from the North Esk River resulted in the largest flood since 1969. The levees held, limiting damage; however some unprotected homes and businesses near the Tamar Yacht Basin, Newstead, St Leonards and Nunamara were inundated and Invermay was threatened. Traffic was disrupted due to parts of the city being cut off. The City of Launceston relied heavily on social media to communicate regular updates and evacuation notices, which kept much of the community well-informed.
*Flood events are measured in cumecs, which refers to cubic metres per second, and are recorded by stream gauges.
The Flood Levee Project began in the 1960s however the need for a system of levees was identified after the devastating 1929 flood.
A series of levees - some as high as four metres - were built as part of the Flood Levee Project to protect the low lying areas on the flood plain, separating the city from the rivers. These levees have now been repaired and rebuilt.
These levees require regular and ongoing maintenance. While they are unlikely to fail, the levees may be overtopped in an extreme flood event.
Any levee system may fail. Those in Launceston are no exception: they may collapse or water may flow over the top of them, and the adequacy of the system can't be guaranteed. Should the levees fail, some properties in Launceston may be affected by flood waters isolating the property or even rising above the floor level.
It's important the community is educated about this risk, preparedness, evacuations and recovery during a flood event.
Below are key suggestions but for detailed information on what to do before, during and after a flood event, please read our Flooding in Launceston brochure(PDF, 1MB).
- Flood waters can be dangerous no matter what the depth is and we don't know what is beneath the surface
- Listen to ABC Local Radio 91.7FM and watch the City of Launceston's social media pages such as Facebook for regular updates and official evacuation notices
- Should you be required to evacuate your home, an evacuation siren will sound and emergency personnel will be active in the area
- Leave before flood waters arrive and lock your home
- Take your pets secured in a pet container, on a leash or muzzled
- Go to the home of a family or friend or to a Council-run Evacuation Centre
- Do not drive, swim, walk or wade in flood waters
- Never drink floodwater and wash your hands and feet thoroughly with soap and clean water. Floodwater can contain sewerage and/or chemicals
- Stay clear of fallen power lines and electrical wires as electricity passes easily through water
- Stay away and keep children away from storm water drains: during a flood, water rushes through these systems which are usually dry for most of the year. Also, be careful of slippery surfaces which can cause falls and injuries
- Be aware there may be displaced and stressed wildlife including snakes and spiders inside your home and yard. They will be looking for somewhere dry, too.
- Call your insurance company or landlord as soon as possible. The City of Launceston can provide information about hardship grants or charities that may be also able to assist
- If you return to your home or business, be alert, tread carefully in protective clothing and do not touch electricity sources until a qualifies electrician has checked all of these
- Once you have returned to your home or business, use a permanent ink pen to mark on a wall the maximum height of the floodwater
- Take photos of any flood damage to your home or business
- If you're unable to return to living in your home due to flood damage, the Department of Health and Human Services can help with temporary accommodation.
Contaminated floodwater and mud can carry an increased risk of infections and diseases. Floodwater can be contaminated with sewerage, animal faeces, chemicals and debris.
Avoid contact with floodwater if you:
- Are prone to infections, particularly young children, pregnant women, the elderly and people with chronic diseases
- Have broken skin or wounds. If you get any cuts or abrasions or other wounds clean with soap and clean water, cover with a dressing, and see your doctor if you have any concerns.
- Wash your hands with soap and clean water or a hand sanitiser after having contact with damaged material, floodwater or mud, before preparing or eating food, and when going to the toilet
- Throw out any medicines that may have had contact with floodwater. If your property has been without power and you have medication that requires refrigeration it may need to be discarded. Check with your Doctor and replace medications as soon as possible
- Dispose of any food that has come in contact with floodwater
- Wash the outside of any tinned food that has come in contact with floodwater, or sanitise it in bleach as soon as possible.
Injuries from falls can occur when cleaning up after a flood. Here are some tips to keep you safe:
- Seek assistance if cleaning up after a flood if the task is too big for you. Ask family, friends or neighbours to help, or contact the State Emergency Service
- Consider using a walking pole, such as a broom handle, to guide you safely around. Muddy surfaces can be slippery and can result in falls that could cause fractures and other injuries.
Snake and spider bites
Bites can occur from snakes or spiders that have taken refuge in your house or among the debris after a flood. Be vigilant when returning to your property: watch for snakes and spiders that may be hiding inside the house or debris.
Receding floodwaters and pooling water from heavy rainfall provide perfect breeding grounds for mosquito breeding, potentially leading to outbreaks of mosquito-borne infections. Although mosquito-borne diseases are typically associated with tropical climates, there have been cases of Ross River Fever reported as far south as Tasmania. Use insect repellent, wear long, loose light coloured clothing, empty and drain any containers and drains where water has accumulated to help prevent mosquitos from breeding.
For more detailed information please read and download our Flooding in Launceston brochure(PDF, 461KB).
Everyone must take particular care when they are in the vicinity of the storm water system as storm water drains, manholes, pits and grates pose a danger in both wet and dry weather.
The storm water system criss-crosses the city taking rainwater away from our streets and homes, sending it to the ocean. The system is more than 438 kilometres long, which is approximately the distance from Launceston to Hobart and back.
Some sections of the storm water drains are only a few metres long but others run for kilometres. They consist of pipes that narrow down, and expand back out. They have debris traps and deep pits with no ladders - and no means of escape.
When it is not raining they are homes to rats, snakes and spiders. When it rains, the pipes flow to full capacity, sucking in anything they can from bicycles to wheelie bins. The storm water system is dangerous in the dry and can be deadly in the wet.
Manholes indicate a change in direction for pipes. Manhole covers weigh between 20 and 30 kilograms (the same weight as a large full suitcase). When really full, manhole covers can sometimes be lifted and thrown by the pressure of water below. That means a person wading through floodwater risks falling into an open manhole full of water. Then, when the water begins to subside, it can rush in like a whirlpool, sucking you in.
A grate is constructed of steel weighing between 80 and 110 kilograms (the same weight as a small motorbike). Do not lift storm water grates or lids under any circumstances as these could cause serious injuries.
Storm water pits
Storm water systems have pits and debris traps which range from 1.2 to 3.6 metres long. The pits have no ladders and therefore no way to get out.
Fast moving storm water
Flowing storm water and hidden debris can easily knock a person over and sweep them away, possibly into storm water drains. It also has the potential to sweep cars of flooded causeways and roads. Never drive through flood water. Turn around and find a safer route.
Roads are usually flooded before properties. It is important that you stay informed of local road conditions to prevent you and your family becoming isolated. Many drivers rescued from flood waters report that they were in a hurry to get home safely, using this as an excuse to drive through floodwaters. Regardless of the type of car you drive, driving through flood water is extremely dangerous.
- Most flood-related deaths occur at night and involve cars driving on flooded roads;
- Creeks and rivers can rise very quickly and the road surface can wash away making water much deeper than it appears
- Once cars are swept downstream, they will often roll to one side and perhaps flip over entirely leaving the driver and occupants little time to escape.
Road condition updates can be found on the Tasmanian Police website.
Three short films have been created by Tasmanian Visual Artist Karen Revie, Invermay Primary School and Big Picture School. The 'Floodscapes' films each have a theme; Community Wise, Pet Wise and Water Wise and will be used for awareness campaigns, and during emergencies.