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Hydrowood underwater logging success

Sassafras hydrowood

Sassafras hydrowood

The directors of a unique underwater logging operation, underway in a remote western Tasmanian location, say they are pleased with the outcome of their first online timber auction. Source: ABC News

The call for tenders closed and general manager Darryn Crook said 36 of the 38 logs offered were sold at a price well above the average for terrestrial logs.

“It’s undoubtedly a unique product. We’re finding beautiful timber with some unique colouration from the time underwater. The black heart sassafras is particularly special. Some of it has a green colour to it,” Mr Crook said.

Developed with a $5m federal grant by Hobart-based forestry company SFM, Hydrowood uses boats and barges to access logs that were inundated by the flooding of Lake Pieman in 1986.

The pride of their fleet is what they call Hydrowood One, a unique vessel incorporating a fixed excavator fitted with a custom-made telescopic arm and waterproof harvesting head.

The arm can extend to a depth of 26m below the surface of the lake to grip logs and cut them with a chainsaw fitting.

Specialty timbers like myrtle, sassafras and blackwood are loaded on a barge and pushed, rather than towed, back to a log-yard base on the shore of the lake.

On board the workhorse vessel of Hydrowood fleet, the Snipe, Mr Crook revels in his newly acquired maritime skills. However, pushing a 30-tonne barge-load of logs into a headwind means that top speed on this reach of Lake Pieman is only 1.7 knots.

“Looks like we’ve got 20, 25 knots of breeze and it’s going to push us into the landing area,” Mr Crook yells above the roar of the Snipe’s diesel engine,” he said.

“Driving the Snipe with the log barge in front of it is sort of a cross-over between drifting and pushing a shopping trolley.”

Mr Crook has worked in forestry in different locations around the country, but the Hydrowood project, unique in Australia, is the first that has required him to have a coxswains ticket.

Hydrowood director David Wise, who co-founded the company with SFM managing director Andrew Morgan, said the seed of the innovative idea came from the clouds.

“I work as a pilot as well so I was flying over the west of Tasmania and saw a lot of the trees in the water in the Pieman and the Gordon schemes, and that sparked the idea,” Mr Wise said.

“With a lot of help from the hydro and the State Government, we did a feasibility study right where we are now, at the end of the Argent Road, and the timber proved to be solid.

“We’re about to go out into what was the Pieman River Valley. It was flooded in the late 80s, so effectively we’re floating across the top of the submerged forest.

“Our Hydrowood One operator, Will, he cleared this channel we’re travelling along in the first week. The map on the screen there beside you is a survey map of what’s beneath the water. The red dots are the bigger trees.”

The Hydrowood One vessel is impressive in action, the long telescopic arm reaching deep beneath the surface of the river before effortlessly plucking another forgotten log from the flooded forest.

Logs are quickly hoisted into the air, streaming watery run-off for a few seconds before being added to the growing pile on the barge, moored hard against the harvester.

The company believes the resource at its current location should last for four to five years.

They are already scouting other possible log recovery operations, including the Gordon scheme and even interstate locations.

Back at the Argent Road log yard, itself a long drive from the Murchison Highway south of Rosebery, log grader Stuart Snare is assessing and trimming the landed logs.

“This is totally different to all other log grading I’ve done. There’s been some very interesting coloured logs come out,” Mr Snare said.

“There doesn’t seem to be any sap-wood on them either, which is a very good thing. It maximises our recovery.

“I’m not a scientific person but obviously being in the water has done something to the logs. They’ve been in there 30-odd years.

“The sassafras in particular are a very unique quality. I’ve never seen green sassafras before.”

The Hydrowood operation has been welcomed by woodcraft workers in Tasmania, including boat builders and furniture makers who have all but run out of some specialty timbers — at least in the sort of size and quality they need.

The timber from the operation is being milled at Wynwood, in Wynyard, where lots for this week’s auctions were also available for viewing.