Significance:

The Lower Lakes and Coorong contain a high diversity of ecological systems and species including many of particular conservation significance (at National, State and Regional level).  The Coorong is recognised as one of the top six water bird sites in Australia and is listed as a wetland of international significance under the Convention of Wetlands (Ramsar, Iran, 1971) and the ecological character at the time of nomination is supposedly protected under the EPBC Act 1999.  The Lower Lakes and Coorong region is also of high cultural value to the Ngarrindjeri people who maintain a strong connection to the land, fish, birds and other living things.  This area underpins significant tourism, recreational and rural industry also at extreme risk from lack of water and poor quality of available water. The area is significant globally because it supports more than 1% of the global populations of several Palaearctic migratory waders (up to 20% for Sharp-tailed Sandpipers)

Threat:

Current regulatory structures including barrages and excessive water extraction have for many years placed stress on the natural systems of the Lower Lakes and Coorong by changing the volume of water and seasonal pattern of remaining flows, exacerbated by the current drought.  The ecology of the Lower Lakes and Coorong has changed under that stress with altered habitat for aquatic plants, macroinvertebrate, fish and tortoise species, migratory and sedentary birds.  Studies have shown there has been an ongoing decline in biodiversity and population abundance for various plants and animals

The security of water for Adelaide and Murray communities is also at risk due to the current drought and over-allocation of water for human uses.  A temporary weir is proposed by the Government of South Australia to reduce water flow into the Lower Lakes, thereby reducing water loss through evaporation.  This proposal does not address the ecological decline for the Lower Lakes and Coorong and may significantly exacerbate the current decline.

Action Required:

In order to restore and conserve the biodiversity of the Lower Lakes and Coorong immediate reduction in water extraction up-stream is required.  This is to prepare for flushing flows into the Coorong that would emulate natural, seasonal patterns as far as possible.  Scientists estimate a minimum of 1000GL is required to fill the Lower Lakes, then more required to overflow the barrages into the Coorong.  Given there is only 1850GL of active storage in the basin the expectation is grim.  There is a drastic need to reduce the concentration of accumulated salt well below the upper tolerance limits of some of the key aquatic species, before other recovery strategies can be considered.  There is a need to sustain some of the key flora and fauna until such time as environmental flows are returned.  The investment in environmental flows will be able to trigger a positive ecological response and to warrant the expense of triage intervention strategies (eg pumping/exporting highly saline water out to sea).

This is a national crisis which requires the immediate attention of our national leaders, both State and Federal. An April 2008 report by the South Australian Murray-Darling Basin Natural Resource Management Board concludes that `the decline in the ecological character [of the Lower Lakes and Coorong] can only be halted and reversed if substantial fresh water inflows are received within the next six months’. This requires a change in the current arrangements for the release of water from the Menindee Lakes in NSW. Achieving this must be a priority for the next COAG (Council of Australian Governments) meeting.

Our Heritage At Risk Nomination 2007