The ultimate pipedream?

Drought proofing South East Queensland in anticipation of 1.04 million additional residents by 2026 (or 3.9 million in total), as well as providing for the industries that employ them, will require government to find an additional 250 megalitres (Ml) of water per day on top of the 1,000Ml per day we presently use, together totalling 456,250Ml a year.

While damming, greater aquifer use, wastewater recycling, conservation and desalination will provide some relief, it's become increasingly clear to politicians of every stripe that the highest volume of water for the dollar might possibly come from transporting it from where it's in abundance to areas of shortfall. Indeed, during the recent Queensland State Election campaign there was a less than subtle competition over which political party or party member had the most promising scheme to accomplish such a feat.

For example, National and Family First Parties as well as the ALP led State Government have all proposed piping water 1,200km from the Burdekin Basin near Townsville to Brisbane, with Premier Beattie, after an initial balk, going so far as to allocate more than $2 million for a year-long feasibility study to be conducted by the Coordinator-General in conjunction with his Water Grid for SE Queensland. In addition, Kevin Byrne, the Liberal Mayor of Cairns, has argued for a water pipeline from Papua New Guinea to the state's southeast via a dam near Mareeba, with costs to be shared by "piggybacking" it along a 4,000km liquid natural gas pipeline earmarked for the same corridor.

Meanwhile, Federal member Malcolm Turnbull and some relevant New South Wales mayors have been promoting the idea of transporting water to SE Queensland from the other side of the McPherson Range abutting the NSW border, where it's argued that any one of the Richmond, Clarence or Mann River catchments (each experiencing an average rainfall of 1,200 mm a year and known collectively as the Northern Rivers) could have some of their excess water piped over the range to dams or a wastewater treatment plant in Brisbane via a sequence of pumping stations.

Why their proposals won't work as submitted

Although these proposals are steps in the right direction and well intended, each is, unfortunately, partially or wholly reliant on out-of-date information, advocates routes that are less than optimal topographically or technologically, are politically untenable and appear to be costed on the run, or not at all: flaws, we suggest, that would (and should) cause the rejection of any one of them.

For instance:

The promise of an endless Burdekin Basin water supply, on which the first two proposals are predicated, was based on a 2002 study completed at a time when sugar prices were depressed and, as a result, saw minimal water use for irrigation. Similarly, it was written before the water-hungry mining boom was in full stride. It also doesn't take into account the numerous aquifers around the Burdekin River catchment that need refilling first.

The LNG pipeline, originally intended to run from PNG to Brisbane, is now set to end in Townsville, meaning the water side of the equation would no longer be able to piggyback the final 1,300 kms of Mayor Byrne's proposal, thereby eliminating the possibility of cross subsidisation for that portion. Moreover, we believe this shortfall will still be maintained even if the project is brought under new management, which now seems to be the case.

The Premier's latest version of his pipeline corridor from the Burdekin River Basin to Brisbane goes by way of existing and new dams en route, each interconnected. Unfortunately, it also travels along too many undulating and elevated parts of the coastal range to get away from relying on additional, costly pumping and booster stations, let alone expensive lifts over the Burdekin, Fitzroy and Burnett catchments into the upper Brisbane Valley.

The NSW Government apparently sees the Northern Rivers option as uneconomic due, in large part, to pumping requirements, not a little cross-border parochialism and some very concerned farmers fearful of water shortages (like those caused by the Cubbie cotton station's negative impact on flow to the Murray Darling Basin). Critics also make reference to a 1999 study that found if the Clarence River system was called on to "divert substantial quantities of water" it would "present significant risks to the health of riverine ecosystems and those activities and values dependent on them". It's assumed this conclusion applies to the Richmond and Mann Rivers as well.

Despite these caveats there are some virtues for these proposals but they need significant reformulating before there's any meaningful contribution to the resolution of SE Queensland's water crisis. With this in mind the best parts have been extracted, and have been adapted by adding well researched "corrections" as well as some cost saving alternatives to offer two options for consideration:

A two-stage water pipeline from PNG to SE Queensland: our northern option

Lake Kutubu at an altitude of 808m down to Townsville:

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.

It's also hoped that any debate towards this end might precipitate a rational discussion on agricultural water use generally and whether there are some crops that just shouldn't be grown in such a dry part of the driest continent.

We also believe that the acceptance of either option (ie NSW or PNG to Brisbane) begs the question of whether any such venture should or could be implemented outside a well-funded National Water Grid framework, one that not only has the teeth to resolve regional issues but is mandated to negotiate with other sovereign nations. If we can do this for electricity, why not water?

If not now, when?

Since 1970 this region's rainfall has been declining and has endured above average temperatures in 11 out of the last 13 years. Together this has led to a dramatic reduction in dam levels, all at a time when demand is increasing from both residential and commercial users. With this in mind, you don't have to be an Al Gore or Tim Flannery to argue that one of these schemes should be implemented within the decade, not the 30-100 years now being considered for the Burdekin to Brisbane option, and goodness knows what extended timeline on the PNG to Brisbane option.