Jump to content

After The Famine, Flood - But No Relief For Oyster Farmers


Recommended Posts

After the famine, flood - but no relief for oyster farmers

THE NSW Food Authority has closed 80 per cent of the state's oyster farming areas following heavy rain last weekend.

Some estuaries are still mostly full of fresh water from the downpour. This time last week they were in the grip of record-breaking drought, and salinity was climbing. The turnaround from a single large storm has been remarkable.

The move to close leases is precautionary and prevents any risk that oysters in flooded estuaries could be contaminated by pollution.

Only 15 of the 72 lease areas across the state were still open for harvesting, the Food Authority said.

Those still open are in just two locations, the Tweed River and Port Stephens. The closures are part of the industry's quality assurance program, meant to guarantee public health.

None of the estuaries will reopen until testing has confirmed the absence of faecal coliforms, a process expected to take about a week. But more rain could extend this period and have an impact on supply.

The managing director of the Sydney Fish Market, Grahame Turk, said that if the closures were lifted within a week or two consumers should not notice a shortage. The 15 open areas would pick up any shortfall, he said. One area almost certain to be closed longer is the Tuross Estuary, located almost midway between Moruya and Narooma. The management problems facing oyster farmers along the NSW coast are highlighted by what has happened there in the past week.

A spokesman for the local oyster industry, Greg Woodford, said that until last weekend's rain the lake had experienced a "permanent low tide" for months.

He said the Tuross lake was the sixth-largest leased area in NSW, producing several million dollars worth of oysters a year. But drought had led to the loss of at least 25 jobs in the industry.

The Tuross River has a 1700-square-kilometre catchment, rising behind Cooma, and carves its way through a huge gorge and the Wadbilliga Wilderness before ending in the saltwater lake east of Bodalla.

Last Saturday the question being asked by everyone who depends on the spectacular coastal lake for their livelihood was, how low can it go? The waterway was so drought-stricken there was no historical precedent for how far it might drop.

Although the Tuross is one of the last big unregulated rivers in the state, by last week it had joined a long list of big rivers in southern NSW to have ceased or almost ceased to flow. These included the Deua, Bega and, most importantly for Sydney's water supply, the Shoalhaven. The Pambula and Towamba rivers were no longer flowing and the Clyde, which enters the sea at Batemans Bay, was down to extremely low flow levels.

Inexorably during the past decade, as drought has worsened, more sand has been deposited at the mouth of the Tuross lake.

Early last year, for only the second time in a century, the mouth finally closed.

Last June Eurobodalla Shire Council used bulldozers to cut a channel through the sandbar.

Since the closure the depth of the 13.3 square-kilometre lake had fallen, through evaporation, by about 70 centimetres.

Despite the lake level plummeting, water quality has held up - an oyster farmer's No.1 priority. Where there was still enough depth, farmers had kept their oysters alive by physically raising and lowering their racks every six weeks.

Dr Paul Rustomji, a post-doctoral researcher with the CSIRO's Division of Land and Water, led a field trip up the Tuross last week and said there were no surface flows in the river, and the lake had evaporated down to mean sea level.

But days later, by the peak of the flood, preliminary Department of Natural Resource data suggested 26,000 megalitres of water was coming down the Tuross. By Monday afternoon the lake level had risen by nearly two metres and low-lying businesses and infrastructure were flooded.

Dr Alec Costin, a local resident and a scientist formerly with CSIRO and the Australian National University, said the striking thing about the flood was not its size but that it was filthy.

"Clearly there has been quite extensive and catchment-wide erosion," Dr Costin said.

On Tuesday the council artificially opened the sandbar at the estuary's entrance, releasing billions of litres of floodwater.

Mr Woodford said it was now a waiting game. No one knew how long it would be before the water quality improved enough for oysters to be harvested. And no one was sure if the rains had been sufficient to scour out the sandbar enough to keep the lake open.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...