Having had 30 years in the groundwater industry in SA I am dubious about the wisdom of increasing pumping from the 'new' groundwater resource. Worldwide, and WA is no exception, groundwater levels are dropping due to overpumping. In the long run you can't pump more water from a groundwater aquifer than is being replaced by rainfall. The Sandgropers should proceed with great caution.

I agree, Dave Clarke, I lived in Phoenix, Az, for 12 months and they have had all kinds of problems from sourcing more water from the aquifers than was being replaced. Not only did this increase salinity but due to the concentration of pollutants, many towns in Arizona ended up with contaminated water.

Before we proceed with anything we need to look at reducing water wastage and improve on water collection - residential (many home owners currently install tanks) however, property investors could look at water storage in the homes they rent out and large business could set an example by installing water tanks on their industrial sites.

The average person can't do it all by her/himself.

There is no doubt we currently waste too much water - there is much to be gained by being rational about saving water and then evaluating what our long term requirements are.

Welcome to OLO Dave.

My sentiments exactly. This has already manifested itself very significantly in Perth with the unsustainable drawdown of the Gnangara Mound, leading to the drying of swamps and cessation of water flow through some of the Yanchep Caves. Perth has come to rely very heavily on this water resource. Water from this aquifer also supplements supplies to the wheatbelt and goldfields, as Phil Playford states. Heavy utilisation of this aquifer is fairly recent, but there are already major problems with it.

Many would argue that the aquifers of the Yarragadee Formation are much larger and deeper and therefore much less prone to drawdown problems. But they are talking about a “sustainable” extraction rate of 300GL/year (45GL initially), which is enormous, and this is likely to get much larger if the population of the southwest keeps growing at the current rate.

I have learnt to be very wary about the use of that word ‘sustainable’ by anyone who is in any associated with supplying a resource or commodity to continuously increasing demand base.

However, I would still be in favour of tapping this resource, but only on a number of very strict conditions;

1. implementation of very significant water conservation and recycling measures

2. relief of extraction pressure on the Gnangara Mound as soon as possible, allowing it to recover and thus minimise further damage to swamp and cave ecosystems

3. reversal of the absurd idea of super-energy-intensive desalination plants

4. a limit to the extraction rate to something far less than 300gigs.

5. and most importantly by far, implementation of limits to human expansion and population in the southwest, that are not far above current levels.

Perth uses about 560 Gl/yr compared with Sydney at 480 Gl/yr with approximately three time the population. Direct users take 300 Gl/yr in addition to the Water Corporations 260 Gl/yr.

On creation of the Water and rivers Commission there was an issue of how much scoping investigation the Commission should do compared with the proving of resources by a proponent. The Commission tried for years to obtain sufficient funding investigation, monitoring and analysis of resource use but was unable to achieve funding from Treasury. in latter years the Commission was actively seeking resource management charges as a means of funding the required resource management.

Professor Playford's comments about the reaons for the amalgamation of the DEP and the WRC are incorrect and do a disservice to the then Board of the WRC. As the past CEO of the WRC I can verify that the reason for amalgamation was a management fad under the MOG review of Dr Gallop, and a reaction to some simplistic complaints about having two regulators.

The Commission's view was that the Water Corporation should have done the deal with Harvey Water years earlier and obtained 50 Gl/yr for $250 million cf $390 million for desalination. Further if the Commission had had the funds it would have been drilling and scoping the SW yarragadee. It tried continually to get investigation going in the SW.

In the event the State was forced to wait until the desalination enthusiasts had their day.

The creation of the Department of Water is belated recognition that water is too important to operate without a resource Manager which can integrate the environment, social and economic factors.

The critical question now is; will the Department of Water be given sufficient funding and allowed to fulfill the proper role of resource manager as is now being cried out for by the SW communities. Investigation drilling and monitoring are necessary but not sufficient the full management suite of optimizing for State good, must be invoked.