The ultimate pipedream?

Presuming there will eventually be a 1,200 km, 600mm-700mm pipeline carrying liquid natural gas from Hides in Papua New Guinea’s Southern Highlands to Townsville via Charters Towers, we would argue that the easement for such a project could also accommodate a water pipeline, where the sharing of construction, operation and maintenance would go a long way to reduce the cost of each. One would think this would be an important consideration in light of recent calls for the whole $7 billion LNG project to be abandoned or indefinitely deferred on the grounds that it will take substantially more money to complete than originally budgeted for.

The water component of this synergistic effort would rely on, for example, six 1.5m diameter mild steel pipes, in parallel and stacked, and drawing a potential 250,000Ml of water a year from the 4,924ha, 70m deep Lake Kutubu, which is83 kms southwest of Hides and PNG's second largest body of water. For all intents and purposes this source would never run out as it is constantly replenished by subterranean and surface streams as well as enjoying an average yearly rainfall of about 4,500mm (Brisbane receives only 1,146mm a year).

From there, both sets of pipes would run 265km down the Kikori River watershed to Kopi on the PNG coast, then go 500km underwater across the Torres Straits to Bamaga on the northern tip of the Cape York Peninsula before heading through Coen, Chillagoe and Charters Towers, where it would cross the Dividing Range along the Flinders Highway and terminate in Townsville with the gas pipeline probably going to the power station, while its water counterpart would end up at a junction with Queensland Rail’s railway easement heading south along the coast.

Although some pumping or booster stations will probably be necessary further along the route, there's the real possibility that Lake Kutubu's 808m elevation and precipitous downward slide to the PNG coast would eliminate this need for quite some distance, since the pull of gravity from such a height and angle would provide a significant push on its route south (How far? Only a proper hydrologiccal study could quantify this as friction and gradient must be factored in). When pumps are required, however, it's not unreasonable to assume they could be powered from LNG, which will clearly be available nearby, or even a steam-LNG combo, to take advantage of the proximate water source. Indeed, in its early days most of the eight pumping stations along the Goldfields pipeline were steam powered.

Bringing water from Townsville to Brisbane: the benefits of laying pipes along the coastal rail track easement

From Townsville south, instead of taking the state government's preferred and more expensive route further inland, we would lay water pipes within the 1,367km Queensland Rail track easement along the coast to Brisbane, either above or underground as conditions dictate.

Among the many reasons this option may be the most cost effective is that in order to serve train use the gradient along the way is never more than 1 per cent, thereby almost obviating, or at least greatly reducing the need for pumping or booster stations. Of equivalent importance, placing this pipeline so close to the existing tracks would facilitate construction by making it easier to bring in materials and workers plus make for less troublesome maintenance and upgrading. Needless to say, these advantages should significantly contribute to a reduction in overall cost.

When the pipeline and its contents finally arrives in Brisbane it could be routed to, for example, a cluster of covered reservoirs to preclude evaporation or directly to wastewater treatment plants closer to Brisbane, the latter being the most promising because the water would ultimately have to end up there anyway.

Piping water from NSW's Northern Rivers to SE Queensland: our southern option

A credible alternative to the problems stated above (at least if the environmental concerns are ironed out and the potential water draw is of an adequate volume) would be to pipe the excess Northern River water directly to the coast then up to the mooted Tugun desalination plant, where it's eventually carried to the same dam or wastewater treatment facilities as the plant's: a route that would be mostly downhill or on a flat surface therefore minimising costly pumping impositions.

Access to this water would be in conjunction with the Queensland Government buying out the 1,000km2 Cubbie Station cotton farm at Diranbandi in the State's southwest (as it tried to do four years ago but found the offer rejected by Canberra).

Cubbie Station's storage dams hold up to as much as 500,000Ml of water, or about the same amount as in Sydney Harbour, and taking them out of use, as well as the 14,000ha of land they're meant to irrigate, would allow the Balonne River to flow naturally into the now stressed Murray Darling River Basin This could also refill the Narran Lakes Wetlands, which lost more than 3/4 of its water due to upstream cotton irrigation and, consequently, has had a devastating impact on NSW farming in the surrounding area and in the Basin.

In any case, such a move might, in turn, encourage the NSW Government to pump its abundant Northern River water into SE Queensland as part of a Water Trading Credit Scheme, particularly since such an effort might give it political backing from Murray Darling Basin's farmers.