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Facts from 2009

Fact: There is not enough freshwater

Due to the perfect storm of over extraction, drought, and climate change, there is simply not enough water in the Murray-Darling Basin to meet all needs.  The CSIRO forecasts a long-term decline in flows at the Murray Mouth of 24% to 30% (ref CSIRO).  Human needs for water are also increasing with Adelaide's population projected to increase by 40% by 2026 (ref ABS).  Read the FAQ for more information.

Fact: Before 1940, the Lower Lakes were part of a vast estuary with the Coorong

Before the barrages were built in 1940,  the Lower Lakes were part of a vast estuarine ecosystem connected with the Coorong . The Lower Lakes and Coorong supported a range of ecosystems from freshwater to marine ecosystems.  Read about types of estuaries.

Fact: The Lower Lakes evaporate up to 950 GL of freshwater each year

Disconnecting the Lower Lakes from the ocean has produced an annual requirement for 750 to 950 GL of freshwater to replace evaporative losses, which could instead be refilled by seawater (ref MDBC).  It is estimated that the Lower Lakes require 4000 to 6000 GL per year (or thousands of billions of litres) of environmental flow to maintain a healthy freshwater ecosystem.

Fact: The Lower Lakes as a freshwater ecosystem are in decline

Even before the current crisis, the ecology of the Lower Lakes and the Coorong has been suffering biodiversity loss for decades, with loss of habitat, invasive fish species, such as carp, and declining native fish species.  In particular, the presence of the barrages causes an abrupt change in the water environment and reduces tidal range, and is believed to be one of the major factors contributing to habitat degradation (ref MBDC).  

Fact: Parts of the Lower Lakes are turning acidic now

Scientists predict that when water levels will fall to -1.5m AHD in Lake Alexandrina and -1.0m in Lake Albert acid sulphate soils will be exposed. As of August 2009, 200 hectares of acidic water has already been identified at Loveday Bay.  Once the Lower Lakes turn acidic, it will be extremely difficult to recover. Bottle Bend Lagoon is one such devastated location upriver.  The only sure way to prevent this from happening is to keep the acid sulphate soils covered with water, and seawater is the only available water.  

Fact: Low water levels are causing problems that are severe now

The Lower Lakes of the River Murray and the Coorong are confronted with severe problems brought upon by the lack of water.  Each problem is complex and requires its own mitigation strategy.  Problems such as: soil salinization, dust and sandstorms, and threats to South Australia's drinking water supply.  Issues in the Lower Murray or 'Below Lock One' include houses slumping into the river and wetlands turning acidic.

We need to act now.

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