PM's $14m Wetlands & Coorong Rescue Plan.

Diverting 137,000 megalitres of water from the Lower South East to the Upper South East.

The Prime Minister, apparently at the instigation of the USE Program Board, visited the Murray mouth (2nd Feb 07) and announced an initiative to divert fresh water from Drain M (61,000 megalitres) and Drain E (77,000 megalitres) in the Lower South East to resuscitate wetlands damaged by the groundwater drains of the USE Project and to rescue the Coorong.

All thinking, environmentally-conscious Australians would support those aims. The problem is that the initiative is fatally flawed. There have not been the required flows in Drain M or Drain E for nearly 20 years.

Falling watertables have been observed throughout the South East for the last 15 years due to climate variability and below average winter rainfall. It is to be noted that a 10% decline in rainfall corresponds to a 30 - 40% decline in stream flow or surface water run off.

In addition to declining rainfall, catchment water management and land use continue to change. Blue gum and pine plantations, with their avaricious appetite for the interception and extraction of water, continue to expand. Indeed, there is an outstanding approval for a further 42,000 hectares of future plantations in the Lower South East of SA.

Figures supplied from the South East Water Conservation and Drainage Board conservatively estimate annual water use of 42,000 hectares of blue gum as in excess 200,000 megalitres - equivalent to the annual water consumption of metropolitan Adelaide. The volume of 500mm rain over 42,000 hectares is 210,000 megalitres. Rainfall in the Lower South East is greater than 500mm, and if watertables are continuing to go down, then this suggests they are using considerably more than 210,000 megalitres.

It is obvious that water resources of the Lower South East are already over-allocated and that reliance on diverting 61,000 megalitres via Drain M and 77,000 megalitres via Drain E to resuscitate salinized wetlands and rescue the Coorong is an illusion.

Funding

Digging drains and associated works relating to diverting water from Drain E and Drain M was costed as a $14m proposal to which the Upper South East Dry land Salinity and Flood Management Plan would contribute $6.5m.

The stop the drains coalition does not consider that the USE Program Board has either sought or received any approval for this diversion of USE Project funding.

Environmental Audit

If the USE Program Board has $6.5m of unallocated funds to divert into an initiative which was never part of the USE Project, it is obvious that there are funds available for an Environmental Audit.

It would also be a matter of public interest how the design, depth and size of drains, including the Didicoolum Drain Extension, have been influenced by the initiative to divert water from the Lower South East.

There is a compelling argument that the plan to divert water from the Lower South East should be included in an extended Environmental Audit.

The Coorong

The Coorong is a considerably altered, highly regulated, saline wetland of international significance. The long term environmental health of the Coorong is under threat because of lack of water, in particular lack of water from the Murray River which flows via Lake Alexandrina and Lake Albert into the Coorong.

In the last major flood in 1956, the level of water in the Coorong rose approximately 1.5 meters. The township of Meningie, on the shores of Lake Albert, was flooded for a period of months. Now, with the locks and barrages and controlled flows of the Murray (when there is sufficient water!), the Coorong's rise and fall is a small fraction of what it was before regulation.

In 1983 the Coorong was declared a Ramsar Wetland of International Significance. It is a condition of the Ramsar Agreement that Wetlands of International Significance cannot be altered.

The Coorong and the USE Dryland Salinity and Flood Management Plan

It was generally agreed that one of the "exit" options for excess water in the USE was via Salt Creek into the Coorong. This was one of the few recognized historic flow paths for the massive natural flooding that occurred in the region before agricultural land clearing.

The quantity and the quality of USE Project water and its impacts on the environmental health of the Coorong have always been a matter of considerable controversy.

Inappropriate and exaggerated USE Project modeling estimated flows to be up to 120,000 megalitres in wet years and 40,000 megalitres on the 10 year running average. Just like the estimates for the Fairview Drain, estimates of flow into the Coorong have been a fraction of modeling predictions. Indeed, annual flows into the Coorong over the last 10 years have averaged approximately 8,000 megalitres. With more than half the network completed, annual peaks in 03/04 and 04/05 only just exceeded 10,000 megalitres.

Inaccurate USE Project modeling has allowed erroneous and environmentally deleterious decision making on a landscape scale by the Project's administrative bodies, the South East Water Conservation and Drainage Board and the USE Program Board.

The source of the inaccurate modeling has been known since 1999, when the Fairview Drain was found to discharge less than 20% of the groundwater that had been predicted in the early 1990s, and arose because of errors in the measurement of aquifer transmissivity. Predicted discharge volumes, and their expected lateral impact on watertables, formed the basis of assessments of the viability of the network, which were not updated prior to the commencement of the current stage of drain construction.

Over-estimated flows into the Coorong led to fears that USE Project water would significantly alter the hyper-saline chacteristics of the southern lagoons. Exaggerated modeling outflows gave rise to the support of 'ponding' as an environmentally necessary and essential 'gain' - as opposed to the flood-in flood-out coordinated surface water management regime which was fundamental to State and Federal government approval of the USE Project.

Ponding in the USE of SA is an environmental disaster. Magnificent freshwater wetlands, such as the Cortina Lakes, have been contaminated, salinized and killed by ponding. The environmental contradiction of deep groundwater drains and ponding compound that disaster.

It is ironic that the flawed initiative of resuscitating USE wetlands and rescuing the Coorong requires fresh water from outside the USE Project area.