Barges steam back as antidote to road-jam

Transporting bulk material such as shingle and logs by sea is quicker, cheaper and more reliable, WAYNE THOMPSON hears.

The former Second World War landing craft Tasman is on a new mission - to reduce the number of quarry trucks needed to feed Auckland's hunger for concrete.

Every day the Tasman chugs quietly up the Weiti River, her sturdy decks piled high with shingle for the Stevensons Whangaparaoa plant.

The vessel carries 480 tonnes a trip from the company's quarry at Kaiaua on the Firth of Thames. This saves 36 truck journeys through Auckland's congested highways, says plant manager Russell McAlees.

The seven-hour voyage is timed to work in with tides to clear the shallow river mouth. It takes 1h 40m to unload the barge at the riverside plant.

Delivery costs, speed and reliability favoured barge transport, said Mr McAlees. Trucks caught on jammed motorways could leave the plant stockpiles low.

Although the Tasman's contribution is slight in comparison with overall demand - the Sky Tower project alone took 30,000 tonnes of aggregates - its success has encouraged owners Subritzky Shipping Line to build a bigger self-propelled barge.

Captain Basil Subritzky said a 47m vessel built in Whangarei would carry a payload of 750 tonnes.

The new vessel was part of the family company's "reversal of history."

It has run ships since 1842, including the sailing scows Jane Gifford and Owhiti.

Materials carried by scows and barges from coastal sources were the foundation for Auckland's growth until the 1940s, when quarries developed on the isthmus.

Other Auckland firms which ran scows and barges early last century, Winstone Aggregates, McCallum Bros and Parry Bros (now Sea-Tow), have persevered with water transport.

Sea-Tow barges deliver Greymouth stone to Onehunga for Winstone, which also use McCallum barges to bring concrete aggregates to Auckland City wharves from a quarry south of Whangarei.

Winstone spokesman Richard Compton said that as a rule of thumb it became more economic to carry quarry products by boat for distances of 100km or more.

But counting against barging was the cost of wharf facilities and double-handling, because all materials must go by road at some point.

Mt Rex Shipping, based near Helensville, is calling for tenders to build a 59m self-propelled vessel to carry stone on Kaipara Harbour from a new quarry near Maungaturoto to its base.

Mt Rex managing director Wayne Collie said barging was cheaper, and rural roads would not stand the pounding from trucks.

"A truckload is 25 to 30 tonnes but a vessel will take 1500 tonnes in one load. The trip from quarry to base is 183km by road but only 60km by barge."

McCallum Bros has a three-barge fleet and spokesman John McCallum said barging would be more attractive as fuel prices rose and motorway congestion worsened.

In addition to its Whangarei-Auckland shingle contract for Winstone, McCallum annually carries 40,000 tonnes of red rock from its island quarry in the Hauraki Gulf, and supplies concrete plants with 100,000 tonnes of sand from Pakiri and Mangawhai.

Sea-Tow general manager Ian Coombridge said barges should do more coastal work because they kept trucks off the highways. His company's barges could move from 3500 to 8000 tonnes at a time. They carried stone and coal from the South Island and had started taking logs from Whangarei to Mt Maunganui for rail shipment to Kawerau.

Mr Compton predicted a swing from trucking to other transportation, especially rail, as Auckland quarries closed and the construction industry hunted further afield for aggregate supplies.