Yet More...

Once you’re past that Kirknie Road turn-off you’re on the approaches to the Burdekin Bridge, with the Inkerman Mill on your right. 

Some mill-related trivia: The milling operation means that, for every ten tonnes of cane crushed, a mill produces almost three metric tonnes of wet fibrous material (bagasse), the residue after the sugar-rich juice has been extracted from the cane. Most mills burn this off, usually generating enough electricity to power the mill’s operations. Inkerman, with a production capability that can handle over two million tonnes of cane, is a large enough operation to generate almost 10 MW of electricity from bagasse, with up to 2 MW exported to the statewide grid.

Some details regarding the river you’re crossing as you head across the Silver Link Bridge.

The Burdekin River, originally named the Wickham River during Captain Wickham’s exploration of the northern coastline in the Beagle in 1839. Leichhardt travelled along the upper reaches of a river he guessed would discharge into the sea near Cape Upstart (it actually flows into Upstart Bay) in 1845 and named the stream after Ann Burdekin, the wife of Thomas Burdekin of Sydney, who had helped fund his expedition.

Draining an area of 130,000 square kilometres, the Burdekin is rated the fourth-largest river in Australia by volume of flow, but the discharge into the Coral Sea tends to vary wildly from something that matches that of the Yangtze (1958, after two severe cyclones) to several months with no flow at all (1923) depending on the quantity, distribution and timing of rain in a catchment where annual rainfall can vary from 200 mm to over 1600 mm depending on monsoon and cyclonic influences.

Interestingly, when Cook sailed along this section of coast in 1770 the area seems to have been experiencing a striking period of below-average rainfall from the mid-1760s to the mid-1780s and four out of five years prior to Cook's visit were dry (details here), so it is hardly surprising to find no sign of the river’s mouth on the Endeavour's charts.

Present day flows are shaped by outflows from the Burdekin Falls Dam, completed in 1987 where the Burdekin River flowing from the north is joined by the Belyando, flowing from the south. The dam forms Lake Dalrymple, covering some 22,400 hectares with water stretching back 50 kilometres along the Burdekin, and supplies water for irrigation in the lower Burdekin, and for urban and industrial use in Townsville. It would have supplied the Water for Bowen project through the Elliott Main Channel had the scheme proceeded.

As far as the bridge, completed in 1957 after a ten-year construction period, is concerned, with a length of 1097 metres, it is one of the longest multi-span bridges in Australia, replacing the previous low level bridge completed in 1913 to link Ayr and Home Hill. What remains of the previous bridge can be seen on your right as you travel northwards.

Remarkably, the structure you’re crossing is actually built on sand, since you would need to go down more than fifty metres at the crossing before you’d strike bed rock. It is the only bridge in Australia built without a firm foothold, supported by eleven waterproof concrete caissons 17 metres across with widths varying from  5.5 to 7.6 metres, sunk vertically through the sand thirty metres below the river bed. Each caisson weighs about 4,000 tonnes. 

The construction cost around six million dollars, employed 235 people and required more than 42,000 cubic yards of concrete, 300,000 high strength bolts and 7000 tons of high strength steel.

Across the bridge, as you pass the service station at Katoora you’re also passing the turn off that will deliver you through Airville to the upriver farming communities of Clare, Milaroo and Dalbeg.

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© Ian Hughes 2013