AT THE POINT
Degree confluence 21°S 149°E, Google Earth
Location: This confluence point is located on private land close to the edge of a mangrove-lined inlet off Sand Bay about 12 km south of Seaforth. The point was reached by Howells Road from and then on foot to within a few hundred metres of the point. The point lies within the Mackay Regional Council area.
The Landscape: The point is on a mud flat adjacent to mangroves on the shore of Sand Bay. In the immediate area the land rises quickly to hills of at least 50 to 100 m elevation. The prominent peak of Mt Jukes (547 m ASL) lies 5 km to the west. The geology at the point is estuarine sediments of Quaternary age (less than 1.6 million years) but in the immediate area the hills are of sandstone and siltstone of Early Permian age (298 to 270 million years). Vegetation at the point is sparse sedges though within a few tens of metres there are mangroves and course tussock grasses. Land use in the vicinity is cattle grazing.
Confluence point location from the south-west (KG, 2008)
Point information and photos: Ken Granger, 2008
WITHIN THE DEGREE SQUARE
The Country: The country within the degree square can be divided into five main landscape types: the off-shore continental islands; the coastline with its many mangrove-lined inlets and high tidal range; the Pioneer Valley; the coastal plains and foothills; and the mountains of the ranges.
The numerous islands and rocks of the Cumberland and Sir James Smith Groups are composed of Early Cretaceous age (141 to 98 million years) rhyolite that form the summits of hills that remain above sea level following sea level rise at the end of the last ice age (between 13 000 and 6 500 years ago). Most of these islands are very steep and have elevations of more than 100 m ASL. Carlisle Island is the highest with a summit at 393 m ASL, less than 650 m from the shore. Most islands are covered with open eucalypt woodlands with Hoop Pine and vine thickets in the more sheltered gullies. Open grasslands are also found on some islands such as Brampton Island.
The islands have much in common in form with some of the rocky capes and coastal hills such as Cape Hillsborough and Mt Bassett (on the north side of Mackay), though the mainland geology is more diverse. Cape Hillsborough, for example is composed of rhyolite and conglomerate of Middle Eocene age (55 to34 million years) while Mt Bassett is basalt and dolerite of Cretaceous age (141 to 65 million years). Most of
the coastline, however, is low-lying with numerous mud and sand banks, wide sandy beaches and tidal estuaries. Some of these sand banks extend well off-shore, for example the sand banks at the mouth of the Pioneer River almost extent as far as Flat Top Island a distance of 2.5 km.
Typical tidal inlet off Sand Bay
Mangrove stilt roots in Sand Bay (KG, 2008)
Wedge Island sand flats Cape Hillsborough
Grass trees Cape Hillsborough woodland (KG, 2008)
Cape Hillsborough geology (KG, 2008)
Sand flats south of Eimeo (KG, 2008)
The tidal range within the degree square is close to the greatest on the east coast of Australia, being a maximum of 6.7 m at Mackay (at the head of Broad Sound, 150 km to the south, the range is as much as 9 m).
The narrow coastal plain has numerous wetlands and lagoons, many of them have been drained to provide for cane growing.
There is an abundant bird and animal population in the coastal area. Some of the more common birds include Orange-footed Scrubfowl, Bush Stone-curlew, Black-necked Stork (Jabiru), Radjah (Burdekin) Shelducks, Plumed Whistling-ducks and Emerald Pigeon. Animals include ring-tailed and brush-tailed possums as well as several species of wallaby. Turtles are also found along the coastline.
Much of the coastline has been developed for either urban or agricultural uses.
The Pioneer Valley has been described as one of the more unusual catchments in Queensland because of its unusually straight course; the rocky nature of much of its bed, especially in the lower reaches; and the irregular nature of its watershed. All this is best explained if the Pioneer River/Cattle Creek is considered to be a vigorous youthful river which is developing along a zone of geological weakness. According to researchers at the University of Queensland, about 8000 years ago, during the early Holocene, the Pioneer River probably flowed through Sandy Creek to the sea, around 10 km south of its present mouth. As the region became wetter and the Pioneer River catchment enlarged, the course of the Pioneer River moved northwards, probably flowing through Bakers Creek to the sea. The present course may have been formed during an extreme flood event in the last 3000 years. Today, Sandy Creek and Bakers Creek drain their own small catchments and flow directly into the sea.
The upper reaches of the Pioneer River and its tributaries such as Finch Hatton Creek and Cattle Creek are very steep and have numerous waterfalls.
Most of the valley has deep and rich alluvial soils of Quaternary age (less than 1.6 million years). Most of the native vegetation has been removed to make way for cane growing which is the dominant land use in the valley. Some of the larger tributaries have been dammed to provide water for irrigation.
The coastal plain and foothills within the square are composed mainly of sedimentary rocks including sandstone and siltstone with ages ranging from the Middle Devonian (384 to 369 million years) to Early Permian (298 to 270 million years). For the most part these hills are undulating and have elevations of less than 300 m ASL. A few peaks, such as Mt Jukes, achieve elevations of more than 500 m ASL. The vegetation on much of this area has been cleared for cattle grazing but some of the steeper country retains open eucalypt woodland, with Hoop Pine and vine thickets on some of the higher country.
Coastal plain and hills behind Seaforth (KG, 2008)
The mountains of the Connors and Clarke Ranges are steep and rugged and range in elevation up to more than 1200 m ASL (summit of Mt William is at 1259 m). They are composed of granite and other intruded rocks mostly of Carboniferous age (354 to 298 million years). Many of the streams that flow across and from the mountains are deeply entrenched and have waterfalls. They are covered in rainforest along the eastern side which grades to eucalypt forest to the west. The area is at the cross-over between the wet tropics and sub-tropics so the forests contain species from both regimes. These mountains are home to several endemic species including the Eungella Honeyeater. Platypus are common in some of the streams such as Broken River.
Much of the mountain area is now preserved in national parks or State Forests.
The Climate: The climate across the degree square is classified as being sub-tropical with a dry winter. The Bureau of Meteorology climate station at Mackay provides representative statistics.
Mackay Met Office (033119) 1959 to 2009 (elevation 30 m ASL)
The highest temperature ever recorded in Mackay was 39.4°C in December 1964 while the lowest temperature was 3.8°C in July 1965. Rainfalls also vary greatly. The highest total of 2744.7 mm was recorded in 1963 and the lowest total of 794.6 mm in 1987.
Extremes of Nature: The point lies within one of the more active cyclone areas on the Queensland coast. The database maintained by the Bureau of Meteorology shows 44 cyclones have passed within 200 km of the point in the 101 years from 1906-7 to 2006-7. Of these eight passed within 50 km of the point. They were: an unnamed cyclone in December 1916, an unnamed cyclone in December 1917, an unnamed cyclone in January 1918, an unnamed cyclone in February 1929, an unnamed cyclone in March 1940, an unnamed cyclone in February 1949, TC Dawn in March 1976, and TC Ivor in March 1990. These cyclones would have produced very high seas and produced significant storm tides as well as widespread wind damage and flooding.
Cyclone tracks that passed within 200 km of the confluence point 1906-2006 (BoM web site)
Numerous cyclones have had a serious impact on the area around Mackay. In February 1888, for example, a cyclone recurved to the east of Mackay and several houses in Mackay were completely destroyed. The steamer Geelong ran aground and two people drowned and another ship was dismasted. In February 1898 TC Eline crossed the coast at Mackay. Many commercial and public buildings were destroyed including several hotels, the Courthouse and several churches. Two houses collapsed and other buildings lost their verandas and roofing. The area received 305 mm of rain in 24 hours and the flooding in the Pioneer River changed the course of the river by reducing its length by 4.8 km (to its current course). All buildings on Flat Top Island except the lighthouse were destroyed.
Undoubtedly the most destructive cyclone to impact on the area was the unnamed Category 4 storm of 21 January 1918. The eye of this cyclone passed directly over Mackay and had a central pressure of 932.6 hPa. Hardly a building in Mackay escaped damage from the wind and the storm tide that hit the town. Three steamers were sunk and the Sydney Street Bridge was swept away because of damage done to its pilons by the impact of the Government steamer that had been swept into the bridge. At least 13 people were drowned in the storm tide and two were killed by flying debris.
The report published in the Mackay Daily Mercury four days after the cyclone provides a very detailed account f this storm:
The destructive period of the cyclone was about ten hours and it was almost incredible the amount of damage that was done in that short period. Some of the residents are able to report that not a pane of glass was damaged in their homes, but they are very few. Of the 1200 or 1400 houses within the Municipality of Mackay, not more than one quarter escaped damage of some kind, and in a great many cases the buildings were levelled to the ground. The town on Monday afternoon presented an appalling spectacle. The damage in most cases consisted of the houses being unroofed, and this particularly applied to the larger buildings such as hotels, churches, public halls and two-storied buildings. As with other classes of buildings some of them collapsed entirely and some sustained partial damage only. The residential area suffered severely. A great many of the residences were thrown down and completely destroyed, while others were unroofed or otherwise damaged. No particular part of the town suffered more than any other part. The damage was general in town and country and confirms the opinion that the centre of the cyclone traversed the district&ldots;..
While the cyclone was at its height another terror, in the shape of a tidal wave, swept the town and caused consternation amongst the fear wracked householders. It struck the coast about five o'clock when the cyclone was raging and it is alleged a wall of water 25 ft [7.6 m] high swept over the beaches; and taking a southwesterly direction submerged the town to varying depths as far out as Nebo Road. It was 5 or 6 ft deep on Beach Road and about 2 ft deep at the Ambulance corner. The water flowed inland in waves, carrying debris of a substantial character with it. In the river the wave played havoc with the shipping, wharves, stores and houses, while a large section of the Sydney Street bridge, which is the main avenue between Mackay and North Side, was washed away&ldots;.
The heavy rain, combined with the big tide, caused a record flood in the river on Tuesday. There is no authentic record as to the height the river rose, as the gauges were all washed away, but the Harbour Master (Captain Greenfield) states that the water rose at least 20 ft. The lower portion of the town was inundated to a depth of [unreadable]. The river broke across below Devil's Elbow into Barnes Creek and relieved the pressure in the main outlet, and on Thursday morning the back water in the land near the cemetery overflowed and crossing Nebo Road, rushed down Shakespeare Street and a parallel street to a depth of 3 ft. It is the opinion of experienced men that had this second diversion not occurred the loss of life would have been enormous. The flood commenced to subside on Thursday afternoon and is already back to normal&ldots;.
Mr J. Shanks and his brother Mr Frank Shanks, also had a terrible experience. They resided in the old butter factory and when the tidal waters entered the building took refuge in what they considered the strongest room in the house and put their wives and families on a table. The water rose above the level of the table and another one was placed on top and as the waters still continued to rise chairs were provided. When everything seemed secure, the kitchen from the house adjoining collapsed and partly demolished the building where the people were. Mr Frank Shanks was rendered insensible through being struck by falling timber and all were thrown into the water. Mr J. Shanks then heroically secured rafts and ultimately, after a fierce battle with the elements, and a most perilous journey, during which his wife and children and his brother's baby disappeared, he reached the Waterside Workers Hall and gained entrance through a window. Mr Frank Shanks afterwards reached Tennyson Street and upon his information a rescue party was organised and a number of people, including Mr. and Mrs. Weir and several who had sought refuge in their residence, together with those who were in the hall, were rescued. The force of the rain was terrible, Mr Shanks remarking that he was bruised all over with the driving rain and had every stitch of clothing ripped off his body.
The record of cyclone impacts is well understood in the area, based on direct experience. Many areas have notices to draw visitor's attention to the risks of high wind experienced in such storms.
Warning notice at Mirani Caravan Park (KG, 2008)
Given its close catchment and very straight course, the Pioneer River is considered to be one of the more dangerous rivers as far as flood is concerned in Queensland, if not Australia because of its short warning time between rainfall and rising flood levels. There have been at least 19 major floods in the Pioneer River since European settlement was established. Of these, the flood that followed the 1918 cyclone and the flood of 1958 are the two highest. Some sense of the impact of the 1958 flood can be gauged from the following first person account of the impact in the suburb of Cremorne that was published in the Daily Mercuryon 19 February 1958.
Mrs A. Wells, who, with her husband, owns a small shop opposite the Cremorne Hotel said: "It was a night of terror. It was not only our losses but those of the other poor people in the Cremorne, too. We (herself, husband, son, daughter-in-law and two children) have only the clothes we stand up in. Mr. Wells said he estimated his loss of stock, house, furniture, refrigeration and such at over ?2000. Some were more fortunate. Mr. and Mrs. L. Herman, with their 18 months old daughter, said after the rescue the water had only lapped the floorboards of their high blocked house and there had been no loss of furniture. However, an outhouse had been lost and fowls drowned. The 30 people who stayed in the hotel told a tale of hunger and fear. The kitchen was flooded and locked and many had not eaten since lunchtime on Monday. Apprentice fitter R. Malone, of Shakespeare Street, who went to help and remained to be stranded on Monday night, gave his description of the end of the Buffalo Hall: "At 6 a.m. the outhouses at the side of the hall went. An hour later, the back of the hall started to collapse, then the right side, and finally it collapsed completely. As the wreckage drifted downstream it hit a section of the approach to the railway bridge, lifted the line and twisted it over." Of the night in the floodbound hotel, Mr. Malone said, "throughout the hotel it did not look as if the building would go, but the water rose 4 ft. up the wall. Everybody evacuated the ground floor and moved to the upstairs section. There was no food and all we had were a few lollies, some cake and prunes. Asked why people did not take advantage of the evacuation on Monday night, Mr. Malone said they thought they would be safe in the hotel.
Several properties in the most heavily impacted area around Foulden were purchased by the Government following the 1958 floods and their owners relocated. A series of levees were also constructed around the urban area on the southern side of the river to protect that part of the town from a repeat of the levels experienced in 1958. The areas on the north of the river were left largely unprotected until some 45 years later.
On 15 February 2008 a deep low pressure system dumped 625 mm of rain on Mackay in six hours and then heavy rain continued for four more days. Strong winds were also experienced causing damage on the northern beaches and to cane crops along the Pioneer Valley. There was only limited flooding from the Pioneer River because the heavy rain was largely confined to the coastal area. None-the-less more than 2000 residences were inundated, some with more than a metre of water over floor level. The majority of badly affected homes were in new residential areas that sat behind levees designed to protect them from riverine flooding. The intense rainfall simply turned the areas inside the levees into dams, thus flooding the town from the inside.
MORE INFORMATION AND PHOTOS OF THESE EVENTS ARE WELCOME
The area experiences around 20 thunder days each year. Such storms can bring intense rainfall leading to flash flooding. They can also bring strong winds and lightning strikes. Lightning can start bushfires if there is sufficient fuel to sustain a fire.
Heavy rain brought by cyclones and severe thunderstorms can trigger landslides on the steeper country. The road that climbs the range at the head of the Pioneer Valley is especially susceptible to landslides and it may be closed for periods as a result.
There are three earthquake epicentres within the degree square recorded since 1900 in the National Earthquake Database maintained by Geoscience Australia. Two of these events were felt strongly in the area and some minor damage was reported in Mackay. The closest quake occurred on 5 April 1950. It was a ML 4.5 event and was centred directly under the northern suburbs of Mackay. The strongest, but more distant quake was a ML 4.7 event on 19 January 1960 that was located about 30 km off Mackay. Only minor damage was reported from both of these earthquakes. More distant events have also been felt in Mackay, for example the 1985 'Proserpine' quake.
The Indigenous Story: The land within the degree square is the traditional country of the Yuwi people.
There is evidence of a lengthy Aboriginal occupation across the area. In the Cape Hillsborough area, for example, there are middens and rock shelters.
MORE INFORMATION WELCOME
Cape Hillsborough midden (KG, 2008)
European Exploration and Settlement: The first European navigator known to have charted the coast in the area was James Cook in HMS Endeavour in 1770. He names several features including Cape Hillsborough, the Cumberland Islands and Repulse Bay. Matthew Flinders in HMS Investigator in 1802 sailed inside the Reef and charted several passages of Mackay. He also accurately estimated the significant tidal range in the area and its cause. Philip Parker King in HMS Mermaid in 1819 also charted the area.
European settlement of Mackay was established in 1862 by pastoralist John Mackay who had 'discovered' the Pioneer River in 1860 during an expedition to find good pasture land. He named the river after himself, however, it was subsequently found that Commodore Burnett of HMS Pioneer had already used that name on a stream near Rockhampton, so he suggested that the name be changed to 'Pioneer', even though his vessel had never entered the river. Mackay overlanded 1200 head of cattle from Rockhampton to the first property in the district at Greenmount, some 19 km from the present day city that bears his name. Mackay's cattle property was subsequently supplied by sea, using the banks of the Pioneer River estuary as the port.
The settlement grew rapidly in its early years. The first post office was opened in 1863; the first land sales were also in 1863; and sugar was introduced from Java in 1865. By 1883 there were at least 25 sugar mills operating in the district and by 1902 most of the sugar lands had already been settled.
Until the post-World War II era, urban development was largely confined to the south bank of the Pioneer River and on Slade Point. Since then, growth has steadily increased to the north of the river, especially in the Andergrove-Beaconsfield area.
Sugar cane dominated the economy of the area for many years though timber getting in the high country, especially the harvesting of Australian Red Cedar, and cattle grazing were also significant.
The development of the new port area just to the north of the Pioneer River and the Hay Point and
Dalrymple Bay coal loading facilities in the late 1960s created a new period of growth. Construction of the facilities and the development of coal fields in the interior around Goonyella and Moranbah led to a boom in growth.
The total population of the degree square at the 2011 national Census was 101,704.
Mackay and its northern suburbs account for 66,873 of the total. Sarina contributed a further 3539, while the villages up the Pioneer Valley such as Walkerston (3083), Marion (2256), Mirani (1011), and Finch Hatton (259) have also been growing as land in Mackay itself becomes more expensive. Coastal settlements such as Seaforth (376) and the villages along the coastal strip from Hay Point to Sarina Beach are becoming increasingly popular as retirement centres.
The population recorded in the degree square probably includes workers or their families who operate as fly-in/fly-out staff in the coal mines.
Mackay is a major regional centre with extensive commercial and public facilities. It has a major public hospital as well as the new Mater Hospital. It is serviced by a major airport with scheduled services to Brisbane. Passenger and freight rail services operate to Brisbane and Cairns while coal trains operate to the fields in the interior. The Bruce Highway passes through Sarina and Mackay and a dense network of public roads covers the cane-growing areas.
Mackay (Google Earth image)
The Port of Mackay contains facilities to import petroleum fuels and general cargos, and export sugar, ethanol, molasses and tallow. It is an artificial harbour constructed inside a major breakwater. The port area also houses a marina for recreational boats and yachts. The Hay Point coal loading facility can ship more than 30 million tonnes of coal a year while its larger neighbouring Dalrymple Bay complex can ship over 80 million tones of coal a year. Both facilities are undergoing major expansion to cope with the demand for export coal.
Accommodation in Mackay has grown considerably over the past decade to cope with the growth in population. A complex of multi-story unit blocks has been built adjacent to the port and represent the most recent development. These units are located very close to the bulk fuel and methanol depots and are in an area of known storm tide exposure.
Unit complex and bulk fuel tanks at Mackay port (KG, 2008)
The sugar industry dominates the landscape across much of the square. There are several sugar mills in the square including Farleigh, Pleystowe, Marion and Racecourse as well as the mill at Sarina.
Tourism is another major industry in the area. There is a resort on Brampton Island and several resorts long the Mackay northern beaches as well as accommodation along the Sarina coast at villages such as Grasstree Beach, and at Seaforth and Midge Point. There is also a resort/caravan park on the edge of the Cape Hillsborough National Park.
Grasstree beach coconuts (KG, 2008)
Most of the square falls within the Mackay Regional Council area with a small area in the north in the Whitsunday Regional Council area. There are 21 national parks and conservation parks within the square. They are: Bakers Creek Conservation Park, Bloomsbury Conservation Park, Brampton Islands National Park, Cape Hillsborough National Park, Eungella National Park, Homevale National Park, Lindeman Islands National Park, Mount Blarney Conservation Park, Mount Hector Conservation Park, Mount Martin National Park, Mount Ossa National Park, Newry Islands National Park, Northumberland Islands National Park, Pioneer Peaks National Park, Reliance Creek National Park, Repulse Islands National Park, Round Top Island National Park, Sandringham Bay Conservation Park, Skull Knob Conservation Park, Smith Islands National Park, South Cumberland Islands National Park, St Helens Gap Conservation Park.
Compiler: Ken Granger, 2009
Edited by: Hayley Freemantle
References: various web sites including EPA, tourism, industry, local government and Bureau of Meteorology.
Miriam Middleman and Ken Granger (eds) 2000: Community risk in Mackay: a multi-hazard risk assessment, Australian Geological Survey Organisation, Canberra.
Gourlay, M.R. and Hacker, J.L.F., 1986: Pioneer River estuary sedimentation studies. Department of Civil Engineering, University of Queensland, St Lucia.