Tuesday, March 3, 2015

Branching out: a Moorabool paddle - changing course

After negotiating the rocks, weed and fallen branches in the section of the Moorabool directly below Batesford during our "paddle" on Saturday, we emerged to find ourselves confronted instead by a manmade obstacle. On the bank above us was a handrail following what looked like a pathway. In the river were large chunks of broken concrete and a little further downstream, the bank was lined with concrete and bluestone.
Apparent pathway with handrail and large chunks of concrete breaking down
What we had arrived at was the beginning of a section of the river which was diverted from its original course during the 1980s.
River bank to the right lined with concrete and bluestone
The reason for the diversion however, dates back millions of years to the Miocene period when much of the surrounding land was covered by seawater. As a result, large deposits of limestone built up, formed from the shells of millions of sea creatures, some of which are still found in fossilised form today. European settlers arriving in the 19th century were quick to realise the potential of these deposits and in 1880, Peter McCann (whose descendants still own much of the surrounding land) registered the Australian Portland Cement Co Ltd and commenced production at nearby Fyansford. Struggling to make a profit in the face of cheap imports and using inefficient production methods, the company went into liquidation in 1895 and again in 1904. Peter died in 1908, leaving the nucleus of a profitable enterprise which, under his youngest son Wesley B McCann who acted as manager, was modernised and overhauled. By 1911 the company came under the control of a group of investors and in July, 1912 as part of the move to modernise the company, a ropeway constructed to carry limestone from the quarry to the cement works (then located at the bottom of the deviation). It was officially opened by the Premier on 12th July, replacing horse-drawn wagons and a section of horse-drawn tramway.
Initially, lime used in the production of cement at the works was quarried from a site just north of the Moorabool River (by my reckoning on a line roughly south of Pennsylvania Ave in Batesford). Lime was crushed on the quarry floor and transported to the works via the ropeway.

Concrete-lined channel above the site of the first quarry
In 1924 the ropeway was replaced by a privately-owned 3'6" gauge railway line which ran from the site of the original quarry, crossing the Moorabool twice on wooden trestle bridges, back to the plant.
Image of the Vulcan Engine #4 crossing the trestle bridge 28th November, 1964.
Image from Weston Langford Railway Photography

In 1931, operations were moved to a second quarry site, which had been developed south of the Moorabool. This is the quarry which is still in use today. To service the new facility, a second section of line was constructed, including a branch which allowed for the dumping of overburden and a 1.3km tunnel - the longest in Victoria until the Melbourne city loop was built - which followed a curving path up from the quarry floor to join the original line west of the second river crossing.
Remains of pylons which supported the trestle bridge
All that can be seen of the second trestle bridge today are some wooden stumps, sticking up above the river's surface. I saw no sign of the more northerly bridge.

Diagram showing the rough layout of railway line running between the quarries and the cement works, taken from Light Railways, vol 120, April 1993 which also contains a more comprehensive history of the quarries.
In 1925 the Australian Portland Cement Company was floated on the stock exchange as Australian Cement Ltd and continued to grow, acquiring a number of other companies over the years, to become Australia's largest cement producer, with production rising to 500,000 tons per annum by 1961 when Wesley McCann retired. The railway operated throughout this time, with one diesel and ten steam engines either shunting on the quarry floor or hauling trucks up and down the 5.6 km line. At the time of its decommissioning in 1966, the diesel and six of the steam locomotives were still in use. All six of these remaining steam engines were preserved and can now be found at the Bellarine Railway whilst the diesel was also preserved but is housed elsewhere.

The floor of the new quarry, showing the diesel and one of the Vulcan engines
as well as the entrance to the tunnel
With the closure of the line, a new method of carting the limestone was needed. To this end, a limestone crusher was installed on the quarry floor with the crushed rock then transferred to a conveyor belt which carried it to the works above. The remains of the conveyor cross the river about 1km south west of the old train bridge and can be seen in passing from the Ring Road.
Remains of the conveyor belt crossing the Moorabool River with the
cement works in the background
In 1980 a bid to extend both the life of the quarry and the supply of lime for the cement works, a proposal was put forward by the company to divert a 4km section of the Moorabool River which was overlying part of the limestone deposit. Moving the river, would add a further 50 years to the lifespan of the quarry, however report by the Ministry for Conservation stated that the increase in lime production would also increase the salinity of the groundwater (which at that time was being returned to the Moorabool) to unacceptable levels.
In the end, a 2.6km diversion of the Moorabool was created with - the company claimed - due consultation as to the needs of flora, fauna and water quality and included measures such as natural curves, tree plantings and pools which would provide habitat for platypus. With these measures in place, the diversion went ahead and to the present day, the river runs through a concrete-lined channel in varying states of repair, along its new course and it was this section of the river which we now found ourselves paddling through in relative comfort. In some places the river was a shallow trickle over a concrete bed, in others, the concrete had broken and fallen away in chunks and there were occasional patches which seemed to have returned to a more natural state.
A section where the concrete appears to have broken away, with an unlined
pool behind, close to the site of the original quarry. Following its closure
in the late 1920s, a section of the river was redirected through the old
excavations, away from the face of the new quarry.
This persisted until we reached a more formed section of the channel which begins at the outflow point from the Batesford Quarry. As far as I can tell, the chute through which the water is returned to the river was constructed at the same time as the realignment took place. Only water which did not exceed acceptable levels of salinity was returned to the river with the remainder pumped to Corio Bay. Google Earth shows water flowing through the chute in January, 2010, but dry as early as 2004 and as late as 2013, either side of this date.
Outflow chute from the nearby quarry
Now, however, it is flowing and in use as a result of an environmental win for the Moorabool which occurred in 2011 when the then Victorian Coalition Government reached an agreement with various water and environmental authorities and the current quarry owner Adelaide Brighton Cement Ltd (ABCL), to return ground water pumped from the quarry, to the Moorabool instead of the bay. The agreement allowed for a return of about 8 mega litres per day (around 3,000 mega litres per year) to the lower Moorabool River, helping to improve environmental flow levels below that point for both the Moorabool and the Barwon Rivers.
Immediately below the outflow, the channel is much more formed, with high walls rising to at least a couple of metres - giving the impression of paddling through a drain - for several hundred metres before returning to lower, concrete-lined banks.

High-walled channel
Paddling down the channel
Every few hundred metres from the outflow until the end of the realignment are little weirs which presumably regulate the flow of water as it travels down a fall of about 12m to the end of the channel. At this point, the diversion ends and the river returns to its natural state and original course, passing only a few hundred metres below the Ring Road.

A series of five small weirs in the channel below the walled section
Below this point are the remains of both the trestle bridge and the conveyor belt shown above.
I will finish this post at the end of the channel and with the end of an era. In 2001, the owners of the Fyansford Cement Works (by that time, Adelaide Brighton Cement Ltd) decided to close the plant. But what to do with the quarry? Operating for over 100 years and with more than 100 million tonnes of limestone and overburden extracted by 2001, there remained enough limestone to keep the quarry operational for at least another thirty years.
Other markets had to be found, so Adelaide Brighton Ltd in conjunction with the McCann family developed new products and sourced new buyers. Today, according to their website, they supply a range of lime products both for construction and agricultural purposes and have also taken the opportunity to develop a range of crushed rock toppings and several fine sand products, which come from a layer of sand underlying the limestone which was not previously utilised during the cement works era.