North Stradbroke Island – Natural Hazards and Critical Infrastructure

North Stradbroke Island – Natural Hazards and Critical Infrastructure

Natural Hazards

To view Natural Hazard mapping layers for bushfire, flood and storm tides, or landslides visit the Redlands Coast Disaster Dashboard.

Bushfire

North Stradbroke Island has a very real risk of bushfire, with the majority of the island being identified as having a high to very high bushfire risk. There is a significant level of residential development at each of the three townships of Dunwich, Amity Point and Point Lookout that either adjoin or fall within the high to very high bushfire risk areas. Due to the steep topography of the land, potential fuel loads on the ground and the resultant bushfire behavior, the areas of greatest risk in Dunwich are along Rainbow and Illawong Crescents and the One Mile and Two Mile communities. At Amity Point, the risk areas are to the east of the township, in behind Flinders Beach, effectively surrounding the small Flinders Beach residential community and covering the Flinders Beach camping areas for the length of Flinders Beach to Point Lookout. At Point Lookout, areas on the inland side of East Coast Road are at greatest risk, particularly the ridgeline areas along Tramican and Donahue Streets, and across to George Nothling Drive and stretching further east to Samarinda Way.

The beach camping sites at both Flinders Beach and Main Beach are located within large areas of high risk bushfire hazard. These camping sites do not have mains water supply and are more isolated from services with limited access points than other parts of the island. These factors increase the vulnerability of the camping areas which are very popular tourist destinations during the summer months. Flinders Beach and Main Beach each have 200 camp sites which allows for a large number of visitors to be located within these areas.

Due to the high level of bushfire risk on North Stradbroke Island, a number of government agencies including Redland City Council (RCC), Queensland Fire Department (QFD), Seqwater, Quandamooka Yoolooburrabee Aboriginal Corporation (QYAC) and Queensland Parks and Wildlife Service (QPWS) undertake coordinated hazard reduction burns and maintain fire lines to reduce the impacts of unplanned bushfires; however the inaccessibility of large areas of the island’s interior limits the extent to which hazard reduction burning can be undertaken.

Properties adjacent to bushland areas may be at risk of ember attack should there be a bushfire in the vicinity. During a wildfire, embers can travel up to 3km in front of a fire line which means residents need to be vigilant and be prepared. For more information about bushfire preparedness and what to do during a bushfire, visit the Queensland Fire Department website to create your Bushfire Survival Plan https://bushfire-survival-plan.qfes.qld.gov.au/

Flood Prone, Storm Tide

The potential for flooding on North Stradbroke Island is primarily the result of tidal inundation that would be caused by a storm tide. The greatest effects would be felt to the north of the island from Amity Point along the Flinders Beach areas to Point Lookout. Current mapping indicates that during a storm tide event, the Amity Point community could possibly become isolated as the result of access roads being cut. Flinders Beach area would also experience significant inland inundation toward the Point Lookout end, covering numerous beach camping locations along Flinders Beach and affecting the ability to evacuate from those locations as well as causing the access to Point Lookout from Flinders Beach to become impassible. Point Lookout itself may experience some inundation along Home Beach from Adder Rock, however due to the steepness of the geography at the Point, inundation would be limited to the low lying areas on the coastal side of East Coast Road. Dunwich may experience some localised flooding resulting from tidal inundation along Flinders Avenue and Norfolk Street, affecting the Bradbury’s Beach Caravan Park and properties directly opposite.

Landslide

The steep sandy slopes of North Stradbroke Island lend to the island having the highest risk of landslide amongst the islands of Moreton Bay. Whilst significant areas of high to very high risk are located in the eastern and southern bushland regions of the island away from the townships, residential development within the township areas of Dunwich and Point Lookout does have a risk of landslide. The highest risk of land slippage at Point Lookout, on the island’s eastern coastline, has been identified around Tramican Street, Cumming Parade, Samarinda Way and East Coast Road. In Dunwich, on the western coastline, the areas of highest risk have been identified around Rainbow Crescent and Illawong Crescent. There is a reasonable level of residential development in these areas at the top of the ridge line along with areas at the base of the ridge line. Mitigation strategies to reduce the affects of landslide in these areas are regulated under the Redland City Plan and are based on engineering solutions at the time of the development.

Plants and tree roots help to prevent landslides occurring by absorbing water and holding the ground together. After bushfires, heavy rain combined with a loss of plants and roots can make the ground soft and heavy, leading to a greater chance of landslides. Landsides can carry debris such as rocks and trees downhill and cause serious damage to anything in their path. The risk of a landslide occurring in a burnt area depends on the volume of rainfall, how steep the land is, the amount of remaining vegetation to support the land, the soil composition and the structure of rocks below the surface. QFD assess landslide prone areas after a significant bushfire to determine if there is a landslide hazard risk.

Critical Infrastructure

Critical infrastructure on the islands at the time of a disaster event includes utilities such as power, water, sewerage and telecommunications, and water transportation including ferry and barge services. Impacts of a disaster on these services may have far-reaching long-term effects for island communities.

Sewage

The sewer network operated by Redland City Council covers Coochiemudlo Island, parts of Dunwich, and Point Lookout on North Stradbroke Island. Those parts of Dunwich, Point Lookout and Amity Point not serviced by the sewer network utilise septic systems, as does all of the Southern Moreton Bay Islands (SMBI).

Many of the newer homes, businesses and the primary schools on Russell and Macleay Islands use modern sewerage treatment systems that require power to operate. Therefore during extended periods of power outage the toilets are unable to be utilised or risk failure if used. This limits the number of community buildings that can be used as evacuation centres during a disaster event.

Many of the RCC sewage pumping stations have fixed generators onsite to provide backup power in the event of a power failure. Those that do not have fixed generators have the facilities to plug in a portable generator; several are available that can be taken to any site that requires it.

The most serious effect of a failing sewerage system is the potential for highly infectious diseases to occur including dysentery and hepatitis. Mosquitoes and flies that spread a number of other illnesses can breed in areas where liquid waste reaches the surface. There are also risks to the natural environment including the health of waterways and Moreton Bay.

Water

Water can be supplied to Russell Island via either North Stradbroke Island or the mainland. From Russell Island, the supply is then piped via Karragarra Island to Lamb Island and then onto Macleay Island. The water supply for Coochiemudlo Island is also piped directly from the mainland. The mainland water supply is connected to the SEQ water grid and therefore the risk of the water supply failing is extremely low. However the islands of Karragarra, Lamb, Macleay and Coochiemudlo only have one connecting pipeline. When one of these pipelines fails there will be a loss of supply and emergency supply measures will be put in place.

The North Stradbroke Island townships of Dunwich, Amity Point and Point Lookout source their water supplies directly from the bore fields located on North Stradbroke Island (stored in reservoirs at each township) and again the risk of the water supply failing is extremely low.

Electricity

The electricity supply, provided by Energex to the SMBI and North Stradbroke Island, comes via Russell Island. The supply originates on the mainland north of Cabbage Tree Point and crosses the Western Boating Channel, connecting to the southern end of Russell Island at Rocky Point, then continues north through the centre of Russell Island before branching off to service North Stradbroke Island and Karragarra Island. The electricity supply from Karragarra Island then connects to Macleay Island which in turn is connected to Lamb Island.

This sequence of connections highlights the importance of Russell Island to the electricity supply for SMBI and North Stradbroke Island. There is a substation on Russell Island to assist in ensuring the power supply to Russell Island is more robust and with less power fluctuations. There are a number of transformer connection points on Macleay Island which enables Energex to use generators to supply power to Macleay, Karragarra and Lamb Islands in the event of a major power failure; however this would be a reduced supply. There are also generator connection points on North Stradbroke Island which can provide reduced backup supply to Dunwich, Point Lookout and Amity Point.

The main line that crosses to the southern end of Russell Island is strung on concrete poles high above the ground in a relatively inaccessible area of moderate to high bushfire risk. If the line was impacted by bushfire, Energex would restore the line as quickly as possible given the population on SMBI and North Stradbroke Island.

Energex offer a notification service for Emergency and Planned outages, and other alerts such as upcoming meter read if dogs are onsite or for certain customer service work requests. Click here to go to the Energex Notifications page to Register for this notification service.

The electricity supply to Coochiemudlo Island comes via an underwater line from the Victoria Point reserve at the end of Colburn Avenue and connects to the western tip of the island near the golf club. The line runs underground until it meets the established road network and as such has limited impact from bushfire, tidal surge or flood hazards.

Telecommunications

Landline access to North Stradbroke Island and SMBI is via a microwave link from the mainland to exchanges on the islands. The exchanges on North Stradbroke Island are located at each of the three townships of Dunwich, Amity Point and Point Lookout, and the SMBI exchanges are located on Russell and Macleay Islands. Coochiemudlo Island is connected via a submarine cable that runs from the Victoria Point exchange to the island.

The exchanges on North Stradbroke Island and SMBI require electricity to operate and all have battery back-up systems that operate for a limited period of time. During extended periods of power outage Telstra have generators that can be deployed from the mainland to provide additional capacity. Telstra also have other resources such as a mobile exchange, mobile satellite coverage and mobile base station that can be deployed if required.

There are no mobile phone towers located on SMBI or Coochiemudlo Island; coverage is from towers on the mainland and North Stradbroke Island. Mobile phone towers on North Stradbroke Island are located in each of the three townships which provide good coverage over these areas. The Amity Point tower also has a radio link to Karingal on the southern end of Moreton Island. There are mobile coverage black spots in the non-township areas, beach camping areas, and predominantly in the southern end of North Stradbroke Island and some parts of SMBI.

Other telecommunication issues that could impact the community during periods of power outage include cordless landline phones and access to the internet, both of which require power to operate. With more people using their mobile phones to access the Internet, more pressure is being placed on the capacity of the mobile network.

Connection to the National Broadband Network (NBN) is now available across the majority of Australia, with various connection types for both wired (copper, fibre optic, and hybrid fibre-coaxial) and radio (satellite and fixed wireless). It is important to know the type of connection you have; fibre to the building (FTTB), fibre to the curb (FTTC), fibre to the node (FTTN), fibre to the premises (FTTP), or hybrid fibre-coaxial (HFC), there is also satellite or fixed wireless. The majority of connections are FTTN and FTTP, closely followed by HFC.

It is important to note that any equipment connected via the NBN will not work during a power outage, including VOIP (Voice over Internet Protocol) phones. For more information about what happens in a power blackout for the type of connection at your residence, please go to https://www.nbnco.com.au/learn/what-happens-in-a-power-blackout. Certain connection types can request battery back-up solutions through their internet service provider; battery back-up is required for all Priority Assistance customers who suffer from a diagnosed life-threatening illness.

If you have a medical alarm, emergency call button, autodialler, security alarm, monitored fire alarm or lift emergency phones at your premises, please contact your equipment provider to confirm whether your equipment will work via the network in the event of a power outage. Further information is also available on the NBN website and how to register these devices; this assists the NBN in identifying premises where support maybe be required to minimise service outages https://www.nbnco.com.au/learn/device-compatibility.

Road Network

North Stradbroke Island is accessible by vehicle barge, passenger water taxi or private boat and the three townships of Dunwich, Amity and Point Lookout are connected by sealed roads. There is a public bus service on the island that operates between the passenger ferries in Dunwich, travelling to Amity Point and Point Lookout. Taxi services are limited, however some Clubs offer a courtesy bus. There are a number of inland tracks that are only accessible by 4WD, and the island has two sandy beaches that you can drive on with a 4WD permit; Flinders Beach and Main Beach (permits can be purchased through Minjerribah Camping).

Driving on sand is different to driving on hard surfaces, stay alert and ensure you are familiar with sand-driving techniques; only travel at low tide, drive on the harder sand, do not park or drive in the water or dunes, and remember to slow down for other beach users and wildlife. Beach driving rules are the same as driving on a public road. QLD Police conduct regular speed checks and random breath testing on the beaches as well as the sealed roads.

REMEMBER: If it’s flooded, forget it – BACK IT UP!

Summer months bring rain, cyclones and unstable weather conditions to Queensland. Our weather can change quickly and be unforgiving. Here in Queensland driving into floodwater is the number one cause of flood-related deaths. Cars are designed to keep us safe on the road but once you hit water, it becomes a completely different story.  It doesn’t matter what car you drive, or how good you are at driving – as soon as you enter floodwater, your car can’t protect you. It can happen anywhere – roads, creeks, dams, parks or backyards. Residents should be aware of the dangers connected to floodwater or swift flowing water such as: slippery surfaces; uneven ground; strong currents; sharp objects; electrical current; fences; vehicles; rocks; long grass; tree branches; sewerage; and chemicals.

If you get trapped in floodwater, you not only put your life and the lives of the people with you at risk, but you also put the rescuers lives at risk too.

Localised flooding may temporarily restrict access and cut roads in some areas of Redland City. Please consider this when planning to drive during periods of heavy rain. See a list of the areas that may be impacted by localised flooding.

Don’t wait until it’s too late. Plan ahead, check out the If it’s flooded, forget it website here https://www.getready.qld.gov.au/FloodedForgetIt, and keep yourself, family and friends safe.

Floodwater Safety information also available here https://www.fire.qld.gov.au/prepare/floodwater-safety

 Water Transportation

North Stradbroke Island, Coochiemudlo Island and SMBI are all accessible via vehicle barge and passenger ferry, departing from Toondah Harbour, Victoria Point and Weinam Creek Marina respectively. Along with the barge and ferry service to SMBI, Bay Island Transit System (BITS) also operates the Queensland Ambulance Service (QAS) boat Kitty Kat from Russell Island. The QAS boat is available 24/7 and an arrangement is already in place to transport Energex staff to SMBI in an emergency, if Kitty Kat is not required for patient transport.

The passenger ferries are designed to operate in rough seas and therefore the size of the waves in the bay or the strength of the wind is unlikely to stop the ferries from running – high winds are more of an issue for the vehicle barges. However, the safety of passengers as they board and depart from the passenger ferries and visibility during heavy fog or torrential rain does determine whether the passenger ferries will operate. The passenger ferries are able to land directly onto the island’s foreshores if the jetty or pontoons were damaged or destroyed. The main safety consideration in doing this is the loading and unloading of passengers.

Severe weather and floating debris can hinder the ability of water transport to operate, requiring services to cease until it is safe. This can impact residents’ access to mainland services and supplies. It is recommended island residents ensure they have an adequately stocked emergency kit, with 5-7 days supply of food, water, medications etc.