Water Plan will decimate Murrumbidgee frogs

Rice growers along the Murrumbidgee River are likely to be among the hardest hit if the federal government proceeds with its new water sharing plan. If the region loses 45 per cent of its current allocation as proposed by the Murray Darling Basin Authority, an unintended consequence will be a dramatic decline in the populations of over a dozen species of frog. These frogs have benefited from water being pooled in upper catchment areas for rice production; if the plan goes ahead more water will end up going down to South Australia and over the barrages into the Southern Ocean, to the detriment of flood plain wildlife.

Early explorers, John Oxley and later Charles Sturt, described what is now known as the Murrumbidgee Irrigation Area as a desolate, uninhabitable landscape. That was before irrigation. Today the region produces wine grapes, citrus, apples and stone fruits, vegetables, wheat, barley, oilseeds and, of course, rice.

Proud locals boast that despite the drought, and because of irrigation and the vertical integration of the food industry, 160 semitrailer loads of quality, fresh food ready for the supermarkets of Australia leave the towns of Leeton and Griffith each day, and a further two and a half trains of containerised food for markets around the world. Not all is produced on irrigation farms, but the certainty irrigation provides has facilitated the development of the food industry with value adding occurring locally to an industry now worth between$2.5 and $3 billion annually.

Leeton is known as the headquarters for the Australian rice industry, and is the location of one of Australia's most successful, vertically integrated agribusinesses - SunRice.

In years of adequate water about 150,000 hectares of rice are planted across the Murray Darling Basin providing habitat for an estimated 5 billion frogs. The spotted grass frog, barking marsh frog, plains froglet and Peron’s tree frog are four of the most common species which live in remnant patches of bushland and breed in flooded rice bays and irrigation channels between August and May. Scientists at the Institute of Applied Ecology at the University of Canberra estimate that every hectare of Australian-grown rice produces 33,000 frogs in addition to the almost ten tonnes of rice.

Of course birds eat frogs, and so perhaps not surprisingly the Murrumbidgee Irrigation Area has also become home to thousands of water birds including rare migratory species.

Incredibly the Guide to the Proposed Basin Plan released last Friday does not mention the word “frog”, or “Amphibian” - not once.

The Guide recognises that most of the 30,000 wetlands scattered across the Murray Darling Basin are on private land and states there are 2,442 key environmental assets across this predominately agricultural region.

In fact during the last 90 years through a constant improvement in management, irrigation techniques, fertility and productive capacity the “desolate” plains are now teeming with wildlife. Of course not all frog species have thrived all the time with the endangered Southern Bell frog undergoing recent decline from the introduction of exotic fish and the degradation of some wetlands particularly from overgrazing.

It was progressive politicians who witnessed the devastation and totally dry rivers that accompanied the droughts of the 1860’s and the late 1890’s that drove the early development of irrigation in the Basin: they wanted to conserve water at times of excess, to sustain farming communities even in drought years. Few realise that since European settlement the Murrumbidgee has run bone dry four times: during the droughts of the 1840s, 1860s, 1890s and 1913-1915. It was so dry in the early 1860s that horse races were held in the bed of the Murrumbidgee River downstream of Gundagai.

Water infrastructure is now extensive across the Basin, so, even during the recent prolonged drought, there was enough water in the Hume and Dartmouth dams to provide for the world’s largest ever environmental water release in October 2005 with 513 gigalitres of water (the equivalent of a Sydney Harbour of water) released into the Barmah-Millewa red gum forest which straddles the Murray River upstream of Echuca.

Without the dams, given the severity of the drought, the Murray River would have likely run dry over the last decade - never mind having enough water to flood a very large forest.

When the then Howard government introduced emergency measures in 2006, making water for Adelaide and other cities and towns within the basin a priority, flows from the upstream dams to the Lower Lakes in South Australia were significantly reduced for the first time in decades.

Malcolm Turnbull, then Water Minister, believed the system was in crisis and the Howard government responded to cries, in particular from its South Australian Cabinet Ministers, by drafting a new Water Act.

Back then the leader of the Australian Greens, Bob Brown, was explaining that it has been “scientifically proven” that 1,500 gigalitres of environmental water is needed to keep the Basin healthy and in particular to keep the Murray’s mouth open. Until very recently, this same figure of 1,500 gigalitres was being quoted by Mike Young, University of Adelaide, and other water experts as the best science.

The Guide, released by the Murray Darling Basin Authority last Friday, now claims that the best science establishes that at least double this amount, 3,000 gigalitres, is the absolute minimum, and 7,600 gigalitres is a more realistic target. The major change has not been in the science, but rather expectations have grown within the ranks of Green activists, along with disdain for Australian agriculture, with rice growers in particular increasingly held in contempt.

The new Guide has been touted as an independent comprehensive scientific assessment of the environmental needs of the Murray Darling Basin, yet incredibly there is no justification provided in the 223-page document for the extraordinary revision of what was “scientifically proven” just a few years ago that is the need for up to 7,600 gigalitres when previously 1,500 was considered more than adequate. Incredibly the new Guide even lacks a reference list, normally a minimum requirement for a work of science.

The new water sharing plan, if implemented according to the Guide, will ensure more water is channeled directly to South Australia but no consideration is given to how this will impact on upstream floodplains.

Indeed at the moment, when it rains there is enough water for everyone, but if the proposals in the Guide are implemented, a near permanent drought will become a feature of the Murrumbidgee Irrigation Area and this will significantly impact on the frogs.

It would be prudent for any radical new plan - the new Guide claims to provide a blueprint for the complete overhaul of water management in the Basin - to carefully consider all the implications of phasing out industries that provide important habitat for key indicator species. Yet incredibly the new Guide does not even consider one species of frog. Indeed there is absolutely no consideration of how changes in water allocations, in particular channeling more water directly to South Australia, will impact on the dozen or so species that comprise the 50 billion frogs many of which are reliant on irrigation along the Murrumbidgee.