Now you see it, soon you won't

This pipe, 400m long, will connect the SEA Gas underground pipeline to the Adelaide network. Local firm Seychell Constructions p/l was due to have it in place by mid-September, well before the anticipated first commercial gas flow in January 2004.

The 680km-long SEA Gas pipeline is a $300m joint venture between equal equity partners International Power, Origin Energy and TXU Australia. Laid at a rate of three to four kilometres a day, it will transfer natural gas from western Victorian offshore gas fields to the Pelican Point power station in Adelaide. Subsidiary pipelines will supply gas to towns and industries along the route.

At Magazine Road, Dry Creek, on the northern outskirts of Adelaide, the trunk main from Victoria will be 400m from the Adelaide gas supply. Origin Energy is using Seychell Constructions to excavate, fabricate and install valves and 400mm-diameter steel pipe as the tie in.

“For weight, width and welding it's our most challenging job yet,” operations manager Tony Seychell said. His crew of nine (Origin Energy also had a full-time supervisor on site) included two pressure vessel welders. Working together, they took 1 hours on each butt, which was X-rayed to ensure total closure.

The welders had about 60 welds to complete before the pipe was undergrounded. Of the total length, 84m will be 3m deep to pass under an open creek and domestic gas mains. Directional drilling fixed the route and the pipe was then pulled through. An elbow joint (see photo) took the pipe up to its standard depth of 1.5m. Tony Seychell anticipated finishing within the scheduled 10 weeks

South Australia's gas market is currently almost totally dependent on the Cooper Basin in central Australia via a single pipeline from Moomba to Adelaide. The SEA Gas pipeline, will link Adelaide's gas supply with Melbourne and Sydney and increase security of future gas supplies.

Crews already have laid and buried more than 400km of pipeline between Keith and the pipeline end point at Port Campbell in Victoria. The Tintinara to Adelaide section is due for completion by October.