Geoscience Reference
In-Depth Information
water to maintain key ecosystem functions, key
environmental assets, a productive base and key
environmental outcomes for the water resource
(MDBA, 2010). An important reform was to
separate water rights from land ownership, so
that water 'entitlements' could be purchased
and traded ('allocations' are the quantities of
water that can be diverted annually, depending
on available supplies). Thus, consumers and
the environment (through the Commonwealth
Environmental Water Holder) may own water 'on
paper', but still be allocated little or no water under
drought conditions. Allocations for the 2010-2011
water year remain at 67% in South Australia
(October 2010), even though there is a small flood
event in the River Murray, in compliance with
'pay-backs' required under the accounting system
for water during drought conditions.
In 2004,
The Living Murray
programme
was launched by MDBA to secure water
for environmental flows by June 2009. The
aforementioned recommendations for a minimum
3000-4000 GL yr
−
1
were presented (Jones
et al.
,
2002), and the outcome of political bargaining was
a 'First Step' target of 500 GL yr
−
1
to be deployed
at six 'icon sites' (five Ramsar-listed wetlands
together with the Murray channel). By November
2009, 465.8 GL of water 'entitlements' had been
purchased, but only a small portion was allocated
and delivered, owing to the prevailing drought.
In 2006, an inter-governmental Senior Basin
Officials Group was formed to develop accounting
rules for water sharing when storages fall below
critical levels. The concept of 'critical human
needs' was developed, referring to flows needed
to maintain levels of domestic and industrial (but
not agricultural) water use. These needs have
priority over the environment, which is seen as
a competitor for water rather than a fundamental
component of the water resource.
Given the water crisis, a
National Plan for Water
Security
was announced in late 2006, including
A
$
3.1B to 'buy back' water, A
$
5.8B to increase the
efficiency of water supply infrastructure, A
$
0.5B
to improve forecasting and A
$
0.5B to establish a
new, 'independent' MDBA. The Water Act 2007 set
a new framework to provide water for ecosystem
health before allocating water for consumption,
and established the office of Commonwealth
Environmental Water Holder to purchase water for
environmental flows. The plan later was upgraded
to the
Water for the Future
programme, with an
additional A
2.9B to enable changes in governance
(e.g. water trading), and formalized by an Inter-
Governmental Agreement in 2008. The MDBA was
established in 2008, and its first major task, the
Basin Plan, will be implemented in 2012, or when
existing water plans are completed (for example,
the Victorian government has declared that its
pre-existing plans will operate until a review
scheduled in 2019). Although establishment of
a water-trading market is widely regarded as a
good economic reform, the most recent NWI
audit (NWC, 2009) is strongly critical of delays
in reforms that were intended to address over-
allocation issues. These reforms will be important
in underpinning the Basin Plan.
$
Drought responses
Options for management of the Lower Murray
from 2006 to June 2010 were limited by conditions
unprecedented since barrages were constructed
in 1939-1940, creating raised lake levels which
encouraged the development of local commercial
fishing, dairy and irrigation industries. Falling lake
levels after 2006 had serious consequences for
these industries, and for lakeside communities
reliant on water-based recreation and tourism.
Emergency domestic water supplies were piped in,
and tourism, recreation and agricultural uses were
restricted. As mentioned above (
Present conditions
),
temporary regulators were constructed at three
points to flood acid sulphate soils and prevent
acidification.
When full, the Lower Lakes lose 750-950 GL
annually through evaporation. Concern over these
losses led to proposals that the barrages should
be opened to inundation by sea water, although
this would completely change the character of the
Ramsar wetland (cf. Phillips and Muller, 2006;
Pittock
et al
., 2010). If the barrages were opened,
or removed, an additional weir would be required
near the Murray's entry to Lake Alexandrina at
Wellington
(Figure
29.1),
to
secure
freshwater
