Managing storages

[sorells1trostizz]

I note that the Commonwealth Minister has announced his decision that
it would be contrary to Federal law to approve the further release of
water from Lakes Crescent and Sorell for irrigation. I only hope that
those controlling the release of water from other storages eg
Craigbourne, Tooms, Leake, realise they cannot rely on those dams
refilling every winter/spring as they used to. The Minister clearly
recognises the Interlaken lakes are unlikely to fill in the
foreseeable future. There was an item in The Mercury this week about
the low level of Craigbourne, and Lake Leake is even lower now than at
this time last year (when it was declared to be the lowest since the
lake first filled in the eighteen-eigthies). Lake Tooms was low for
the entire fishing season. Neither Leake nor Tooms came anywhere near
to full last winter/spring. It is a fact that water can be taken only
once and unless repenished by rain those relying on the storages must
get used to either using it frugally or only getting it in an
unusually wet year - when they perhaps need it least. Careless
irrigation and household use has seen some storages at exceptionally
low levels at present. Without very heavy and persistent rains this
winter/spring those users will get their come-upance next summer.

[AC]

Thank you sorells1trostizz, for a very thought provoking post.

It certainly does appear that the use of massive volumes of water for
agricultural irrigation is well entrenched and increasing. The
enormous cost alone of the large scale irrigation equipment that we
see as we drive around the state suggests that, in the presence of
unlimited water supplies, large scale irrigation is very profitable.
Therein lies two problems.

The first is that, wherever there is a possibility of extracting a
dollar from the environment, there will always be those who stand
ready to snatch the opportunity, with little thought for long term
environmental consequences. In using the term environment here, I
mean it in an overall sense. Not only with respect to natural
ecosystems and bio-diversity but also in the sense of our own, human
environment. Tasmanians have long taken for granted, the abundance of
natural resources in this state and have been busily plundering them
for a very long time. Suddenly, I see a day looming where we will be
grieving the permanent loss of what we have so long taken for granted.

The second problem is the one we are now becoming acutely aware
of .... that there is no such thing as unlimited water supplies. If
present conditions persist, then those who have overused this precious
resource will indeed get their "come-uppance" very soon. They will
doubtless suffer economic discomfort, hit the government up for some
much needed cash relief and wait for the rains to come ..... so they
can get back to business as usual. Meantime, many people who haven't
contributed to the problem will nevertheless get to share in the
consequences.

The rest of the population will endure a loss that will continue
indefinately. Every Tasmanian who likes to chase our beloved trout
will see the destruction of their favorite fisheries. It is already
clearly apparent. And there seems little that can be done about it.

I can't help wondering what mechanism exists for the management of non-
Hydro lakes in this State. For example, what arrangements exist for
determining water releases for lakes like Tooms and Leake? Given the
very real liklihood of severe water shortages for domestic consumption
in the near future, are these lakes still being used to provide
irrigation for agriculture? If so, what crops are being irrigated?
Who controls the use of such irrigation water? Who pays for that
irrigation water and how is its use monitored? And finally, is there
any administrative mechanism in place to ensure that those having a
vested interest in accessing such water are not those who control its
release?

Another issue that has been rattling around at the edge of my little
mind is that of cloud seeding practices in the West of the state.
Given the critical water situation which is now faced in the state's
East, is this practice still being carried on in the West? And is it
reasonable to assume that rain that is 'headed off' on one side of the
state, might be prevented from falling in another? In the past forty
years, we have seen the loss of Lake Dulverton and Lake Tiberius in
the Southern Midlands. Back in the sixties, Lake Dulverton was a
large body of water that hosted water skiing and boating regattas.
Today, it would make a very good motocross venue (without water
hazards though!). The current worries about climate change are
certainly reinforced when you look at Lake Dulverton. I just wonder
how 'local' that climate change might be and what is the cause.

Just some thoughts.

Cheers All

AC