AVOIDING any actions that could potentially impact on downstream catchments has been the focus of a submission from MidCoast Water to AGL in response to the company's draft water management strategy for the Gloucester gas project.
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In a draft extracted water management strategy, AGL has indicated how it plans to deal with extracted water which will include up to 730 million litres of a mixture of produced water and flow back water per year from the first stage of the Gloucester gas project.
The proposal of desalinating the water via reverse osmosis technology and maximising the reuse of this water is supported in principal by MidCoast Water, however the water and sewer authority has indicated it has some concern about the practicalities of the strategy.
In reviewing the strategy, MidCoast Water has made several recommendations to AGL, all of which aim to limit any potential impact on downstream catchments.
Avoiding river discharges is one of the main points of MidCoast Water's submission, which strongly recommends AGL extend the proposed irrigation area or increase storage capacity to both reduce discharges to the Avon River and maximise reuse opportunities.
AGL's proposal to discharge water during periods of low flow to "provide stock water supplies to downstream users" is not supported by MidCoast Water, however the county council acknowledges this is an area the company has indicated it would welcome feedback on from stakeholders and community members.
"We do not agree with the idea that such a discharge would improve water quality in the river and maintain environmental flows," Mr Loadsman said.
"We strongly oppose the idea of using waterways as transportation routes for recycled water - such water has to be transported by pipelines."
MidCoast Water is also calling for a comprehensive risk assessment to be undertaken and contingency measures designed as part of any extracted water management scheme.
"We believe the proposed scheme will be very complex with a number of risks associated with its operation."
MidCoast Water has also been critical of the proposed discharge point location and dilution factor indicated in AGL's proposed strategy, where it is proposed up to 1.5 million litres of treated water per day is discharged into Dog Trap Creek, during wet weather when irrigation is not possible.
"We believe it is highly unlikely that such a small tributary can accept this volume of discharge without adversely impacting on the creek."
MidCoast Water has recommended either moving the discharge point or an acceptable dilution factor for Dog Trap Creek estimated.
The monitoring plan presented by AGL has also been found wanting by the water authority and in some cases "highly inadequate."
"Water quality monitoring is proposed on a quarterly basis which in our opinion is highly inadequate - we believe the discharge water pond should be sampled much more frequently, and the location of sampling points should be reviewed to adequately monitor the performance of the reverse osmosis treatment," Mr Loadsman said.