Aqua nullius: the upper Murrumbidgee River

The proposed Murray-Darling Basin Plan has been one of the most controversial pieces of public policy in Australia’s recent history. There has been the predictable divide between irrigators calling for more water to be extracted from the river, and environmentalists, who say too much is coming out already. But between the two, many experts are looking at the nuances of the plan and saying it’s a lot more complex than farming versus nature.

This week, researchers around the Basin will give us their view of how their local area has fared in recent years and tell us whether the proposed plan will make things better or worse. Today Jamie Pittock, Research Fellow at The Australian National University, asks why the Upper Murrumbidgee - Canberra’s local waterway - has been so overlooked by government planners.

The reflections may be glorious, but Lake Burley Griffin is fetid. Sheba_Also/Flickr

The Murrumbidgee River is the second largest source of water flows into the Murray-Darling system. The 1,600 km long river is ranked as one of the two least ecologically healthy of 23 tributary rivers in the Basin. The upper river (above Burrinjuck Dam) drains 13,100 km² of the 84,000 km² Murrumbidgee catchment. It is home to the largest population centre in the Basin: Canberra. Yet the proposed Basin Plan will do absolutely nothing to restore the environment of the upper Murrumbidgee.

Since 1994 the Federal, NSW and ACT governments have adopted many fine words on how rivers will be managed sustainably. Most explicitly, the 2004 National Water Initiative promises sustainable river flows, water markets and catchment-based plans across their political boundaries. In practice, nothing has changed for the upper Murrumbidgee.

In the headwaters at Tantangara Dam, 98% of river flows are diverted by Snowy Hydro to the Tumut River, by-passing the upper river. Tributaries restore 70% of natural flows by the time the Murrumbidgee River reaches Canberra. Fish are indicators of river health. While 70% of natural flows may sound sufficient, fish levels suggest otherwise. The water loss has contributed to the collapse of indigenous fish populations. Species like the Murray Cod and Macquarie Perch are now endangered.

So why won’t the proposed Basin Plan improve the health of the upper Murrumbidgee? The plan does not propose any measures to conserve the threatened aquatic flora, fauna or ecosystems of the upper Murrumbidgee River. It ignores all the headwaters in the Basin. No significant reallocation of water is proposed in the upper Murrumbidgee River.

The Plan is required to conserve river ecology by limiting water diversions in the Basin. The Authority proposes to achieve this by supplying water to 18 “hydrologic indicator sites for key environmental assets”. These are almost all large floodplain wetlands in the lower reaches of the rivers.

The Authority assumes that delivering larger environmental flows to downstream wetlands will conserve, along the way, the different plants and animals that live in upland aquatic ecosystems. But they have not assessed what is required to conserve each threatened aquatic species and ecosystem in the Basin.

The upper Murrumbidgee River on the outskirts of Canberra: pretty but degraded. (c) J. Pittock

The Authority’s approach is questionable, since the federal law enabling the plan is based on implementation of two environmental treaties. Both the Convention on Biological Diversity and the Ramsar Convention codify a key conservation principle: the obligation to sustain an ecologically representative range of species and ecological communities.

Legally the upper Murrumbidgee is aqua nullius. A NSW water licence awards Snowy Hydro all the water that they divert, independently of the rules agreed for the rest of the Basin. Despite national policy commitments, the ACT and NSW governments do not have a shared catchment or water plan. The ACT Government, for example, advises that “A water sharing plan for the entire upper Murrumbidgee River is not practical as water management in each jurisdiction is governed by different legislation” (letter dated 24 January 2011).

There are consequences of such poor governance. For instance, every time there is a flood, Queanbeyan’s water treatment plant overflows and sends sewerage into Lake Burley Griffin. The Queanbeyan City Council’s response is that we were here first and the ACT Government can pay to fix this problem.

The reality is that national water policy, water markets and planning only begin 400 km down the river, below Burrinjuck and Blowering reservoirs.

The plucky residents of Delegate (population 450) successfully fought to get more water to restore some of the Snowy River’s flows through their town from 2002. By contrast, the pampered denizens of Canberra (population 356,000) have ignored the degradation of the upper Murrumbidgee system and have been content to admire the reflections of the glorious public buildings lining the fetid carp pond that is Lake Burley Griffin. The Federal Government rules over a national water policy that it does not apply in its own front yard.

Tomorrow: the Hume Dam, and why regulating flow is about more than “how much”.

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