Emailed letter sent to Perth (Western Australia) media mid August 2007.
Profligate Govt waste of water
following average catchment rain
Dear Perth Media,
There are three ways the Govt could tap readily available water near
Perth without recourse to highly expensive and high impact seawater
desalination.
Each of the 3 areas below has potential to improve water supplies by
about 100 GL per year.
[1] Manage the catchments.
[2] Cut the Gnangara pines now.
[3] Desalinate enough weakly saline Avon and Murray river water
to augment the Agritech Wellington Dam proposal to 100 GL PA.
Some details to expand on the above.
[1] May-June-July rainfall in Perth dam catchments has been
just over average going by data from the BoM stations, Mundaring,
Karnet and Dwellingup. Taking an average of the 3 BoM stations for
those 3 months, 561 mm could have fallen over the 3500 sq kms of
catchments meaning that 1,963 GL of water has fallen free from the
skies.
From my graphic showing the drastic decline in catchment yields since
the mid 1990's, we can see that current yields are ~3%.
http://au.geocities.com/perth_water/ce06.gif
So let's say the last 3 months rain has or will put 3% of 1,963 GL into
dams, there being a delay in flows entering dams, this equates to 58
GL. Not far off what the current Water Corporation "Water Storage in
Our Dams" graphic shows.
Now, it is perfectly clear that we could easily manage catchments how
they were in the mid 1990's and harvest 6% of rainfall.
This Water Corporation graphic portraying actual flow increases after
thinning in the Higgins catchment near Dwellingup, suggests that higher
yields are possible in some areas but we will go with the 6% target for
now.
http://au.geocities.com/perth_water/higgins.gif
So just in 3 short months of average catchment rainfall the Western
Australian Government water authority, Water Corporation, has LOST,
WASTED, refused to HARVEST ~58 GL of free rainwater.
The proposed new Binningup seawater desalination plant is est to cost
~$1 Billion and will produce 45 GL PA. So quite obviously we have to
invest ~$1.25 Billion just to replace this 58 GL of water lost because
the Govt will not manage catchments to a 6% average yield, as they were
in the mid 1990's. Then there are annual running costs.
Just in the last few days on TV news the following WaterCorp cost data
has been quoted for various water sources.
Dams were 16 cents per kilolitre,
The Kwinana Desal Plant $1.20,
proposed Binningup Desal $2.00
So in annual cost terms, using Water Corporation figures, the 58 GL
lost will cost ~$116 million to produce in the proposed new Binningup
desalination plant.
These investment and annual running costs outlined here put some scale
on the cost of kowtowing to ridiculous Green dogmas and refusing to
manage catchments sensibly.
[2] In 2002 UWA water experts said that if the
Gnangara pines were cut and replaced by a mix of housing and native
vegetation, then over 100 GL of water could be saved per year. With
incremental water now priced at the monstrous cost of high impact
seawater desalination, see above, the pines must have a large NEGATIVE
net present value and must be cut forthwith.
[3] Recent TV news about ample river flows for the Avon
Descent white water boat race near Perth, Western Australia, raise an
interesting question. The Avon River joins the Swan River and runs
right through the centre of Perth.
Perth has a water shortage, water users are on restrictions, water
prices are sky-rocketing from 16 cents per kilolitre to $2 per
kilolitre, so why is this water wasting to sea in the Swan River, right
through the heart of Perth. Amazing that there is not ONE word in the
media joining the dots between the abundant water in the Avon, wasting
to sea and the Perth water crisis.
A published paper by several Govt scientists states that over 600 GL of
weakly saline water flows on average each year in the Avon, Murray and
Collie Rivers. This is circa twice the Perth annual water consumption.
Yet over the decades Perth has been blessed with such abundant water
supplies that we use none of this huge water source for town supply.
Agritech at their website,
http://www.agritechsmartwater.com.au/
describe their win win win proposal for desalinating waste water from
Wellington Dam near Collie.
The Western Australian Government Water Corporation has spent years
opposing the Agritech project which is to supply water to the Govt at
60 cents per kilolitre, half the cost of the currently operation
Kwinana seawater desalination plant. A sensible Govt. (is this an
oxymoron?) would say to Agritech: why not increase your project to 100
GL per year and we will see you get the extra water stocks from the
Avon or Murray rivers? Too logical, too easy. This would only save us
from investing over $2 Billion in seawater desalination, or in terms of
annual water costs, would save over $100 million per year.
I note that the media is the beneficiary of $Millions of dollars worth
of Govt advertising.
I note the media rarely reports anything rational about rainfall while
faithfully reporting for years Govt spin about "our drying
climate", including year after year after year after year when our
catchment rainfalls were near average in terms of the last 30 years.
The WA Govt and its Water Corporation (would be better named Lesser
Water Corporation) could rank with the worst water managers on the
planet because of their premature panic into seawater desalination.
The ancient Romans were vastly more skilful and more efficient water
managers than the WA Govt.
Warwick Hughes
You can email me : perth_water AT sign yahoo.com.au
Below are several Blog articles touching Perth water supply issues.
West Australian Premier talks utter nonsense about rainfall
May 22nd, 2007 by Warwick Hughes
http://www.warwickhughes.com/blog/?p=108
W.A. Govt propaganda takes water supply “post rain”
July 10th, 2007 by Warwick Hughes
http://www.warwickhughes.com/blog/?p=121
Colossal Govt. waste of free rainfall
August 7th, 2007 by Warwick Hughes
http://www.warwickhughes.com/blog/?p=126
Perth is not running out of water, water is running out of Perth
August 7th, 2007 by Warwick Hughes
http://www.warwickhughes.com/blog/?p=127
Seawater desalination questions
August 7th, 2007 by Warwick Hughes
http://www.warwickhughes.com/blog/?p=128
Australian Government understating Perth catchment rain
August 22nd, 2007 by Warwick Hughes
http://www.warwickhughes.com/blog/?p=134
Posted 16 August 2007 End for now.