The big friendly giant
TOWNSVILLE’S City Deal is the first ever for Australia.
Under this 15- year intergovernmental initiative, the Water Security Taskforce, led by Brad Webb, released its Interim Report on June 30. It outlines their preferred option for Townsville’s water security.
One key recommendation is that Ross River Dam is no longer adequate for our primary source, and is to be superseded by the huge Burdekin supply.
This is a long overdue milestone. Here are a few details about the Lower Burdekin Falls Dam ( BFD) and its catchment.
Comparison with Ross Dam ( RRD) is the difference between a watermelon and a pea. RRD is at 19 per cent again. BFD at 19 per cent would fill RRD 1.5 times and give us four years of water without pumps or restrictions.
BFD Stage 1 began in 1984 and was completed in 1987. It filled the following year and is fed by 71 rivers and 52 subcatchments. The catchment is more than five times the volume of Sydney Harbour.
Holding back Lake Dalrymple it was built for dual purposes … Lower Burdekin agriculture and as Townsville’s backup urban supply.
The BFD reservoir holds 1,860,000ML whereas RRD’s is 233,187ML. The BFD wall is 876m long and has a 504m spillway, with a drop of 37m.
RRD has an average depth of 3m. In a non- restricted year Townsville uses up to 40 per cent of RRD supply. The equivalent would be 2 per cent annually of BFD.
The Burdekin aquifer is one of the largest in Australia, with an estimated 20 million ML of water and the average groundwater storage above mean sea level is about 400,000ML.
Average annual rainfall for the region is about 962mm.
The Burdekin River has the fourth highest average annual flow in Australia, and is second only to the Murray in economic importance to Australia.
The hydro- electric potential in the Burdekin has been talked about since the 1940s. The proposed stage 2 to raise the wall a further 14m for hydro- electric infrastructure has been thwarted by all governments since.
A Federal Government funded feasibility study is looking into raising the wall just 2m. When the spillway has 0.5m of water overflowing to the ocean ( about 27,000ML) each day. That equates to over half of Townsville’s annual consumption.
Last wet season, BFD overflowed for over three months. The lowest level it has ever dropped to was 38 per cent back in 1994. BFD is now undergoing its first major safety upgrade ($ 100 million).
The dam is one of only two ( the other is The Ord) built by the Federal Government with state collaboration.
It was largely underwritten by the efforts of then Member for Herbert Ted Lindsay MP who acknowledged cross party backing, mainly from then PM Bob Hawke and Queensland Premier Joh Bjelke- Petersen, whose government contributed more than $ 140 million.
In his speech at the 1987 opening of the BFD, Mr Hawke said, “The dam will provide some 850,000ML of water through irrigation, some 50,000ha of grazing land … and 130,000 people in Townsville and Thuringowa will receive a water supply that is guaranteed.
“It is a project which proves again the truth that, through constructive co- operation, Australian governments can perform great tasks and complete great achievements.”
In 1988 our current pipeline was built from the Haughton Balancing and Storage Aggregation and pump station to an open channel behind RRD.
Townsville needs a second 37.5km second pipeline, a new pump station and new treatment plant. The old pipeline is in poor condition and we have no backup in the event of failure.
The question remains whether future council policy will ensure the proposed new infrastructure is used to maximise the increased volume, or leave pumping until level 3 restrictions have been in place for lengthy periods of time, as is the status quo.
It’s difficult to “fathom” why, in 2017, an Australian city of almost 200,000 people is still facing a water crisis.
In 1987 a report commissioned by the council determined supply for Townsville would need to be 214ML a day.
For over a year now we have been on mandatory restrictions of under 100ML a day with stringent fines in place.
The history of the city’s water shortages dates back to 1885. The 1987 precedent for intergovernmental dam funding exists. Surely the City Deal, 30 years later, can rise to the occasion.
The children’s novel about the Big Friendly Giant ( or BFG) comes to mind – the BFD will be Townsville’s BFG.