Adelaide Desalination Plant
The Adelaide Desalination Plant has been operating since 2012, with a capacity to produce up to 300 ML per day with an annual potential production of 100 GL/year. Since 2015, after a 2-year proving period, the plant has been operating in a reduced capacity due to reduced demand and the costs of producing desalinated water. Instantaneous production rates of up to 300 ML/day for 1.5 days per week, as well as maintenance shutdowns during periods of low demand have been typical outputs for the desalination plant.
Due to drought conditions throughout the Murray–Darling Basin, an agreement between the state government and the Federal government has been reached for the desalination plant to produce 40 GL by end-June 2020, with an potential to produce a further 60 GL for the financial year 2020–21, depending on further assessments and negotiations. This will mean that the production capacity of the plant will increase to 240 to 270 ML per day consistently over this period. This is a change to the most recent operations, but is within the range of expected operations of the plant when it was first licensed by the EPA.
The original licence was issued to the AdelaideAqua D&C Consortium constructing the plant in November 2010. When construction was completed in December 2012, a licence was issued to AdelaideAqua Pty Ltd for the operation of the plant. In March 2015 the current licence was reissued to AdelaideAqua, based on the outcomes of an independent review of the monitoring undertaken for the desalination plants operations. When first commissioned in 2012 after construction, the plant operated at a range of production volumes and environmental conditions to confirm the assumptions regarding the dispersion of the saline concentrate through the diffuser outfall.
The EPA has set strict compliance limits and monitoring requirements in the environmental licence for the plant. The monitoring has 3 distinct approaches:
•instantaneous outputs from the desalination plant to control operations in real time
•ongoing monitoring of salinity levels in the marine environment to confirm that the operations of the plant are maintaining the salinity level within 1.3 ppt of ambient conditions at 100 m from the diffuser
•studies of the wider environment to determine if any impacts from the operation are occurring over longer time periods.
A summary of the monitoring data collected as part of the licence conditions is available on the EPA website. This is updated with monitoring data required as part of the EPA licence.
Changes to licence conditions – March 2015
A condition of the operating licence was for an independent marine monitoring review to be undertaken (licence condition number 305-626) of the original licence. The condition required that:
- an independent review of all marine monitoring is conducted by independent specialist(s) as approved in writing by the EPA prior to the review commencing
- all marine monitoring from the period commencing with the issue of the licence and ending 12 months after the project handover of the 100-GL desalination plant is included in the review
- the full results of the review are provided to the EPA not more than 18 months after project handover of the 100-GL desalination plant.
The purpose of the independent review was to provide conclusions about the harm or otherwise caused to the environment by the desalination plant operations, and to comment on the acceptability of the monitoring undertaken to determine levels of harm.
The project handover date for the 100-GL plant occurred in December 2012, and so the compliance date for this condition was end of June 2014. The independent specialist Professor Anthony Cheshire was appointed by Adelaideaqua in November 2013.
The independent review documentation was provided in full on 30 June 2014, in 21 reports addressing the specific licensing monitoring requirement, and a supplementary report considering the overall monitoring and impacts of the desalination plants discharge on the environment. The conclusions of the supplementary report were that the monitoring to determine if harm was occurring was adequate, and that monitoring has indicated that no harm is occurring.
The report conclusions were accepted by the EPA and as such the specific monitoring requirements of the licence were reviewed, and the outcome of the review led to changes to licence conditions and a new monitoring program.
Conditions have been included in the licence which require that the plant must only operate within salinity discharge levels and discharge pressures that have been demonstrated to cause no harm to the environment. The licence still requires the Adelaideaqua consortium to continually monitor salinity levels at specified offshore monitoring points and report the levels to the EPA.
Some changes are that the salinity monitoring at 4 locations, 100 m from the diffusers, has been modified to salinity monitoring at 2 points, 100 m from the diffuser. The requirement to monitor in real time is no longer required, however the data will need to be retrieved regularly to confirm that the measured salinity is within expectations, which is less than 1.3 ppt above ambient salinity. Also ongoing monitoring of fish videos, infauna surveys and subtidal reef occur every 3 years as opposed to annually. This level of monitoring will still be able to determine if environmental impacts are occurring due to the operation of the desalination plant.
A range of background monitoring was required by the terms of the development approval and subsequently the licence issued by the EPA.
The monitoring, commissioned by Adelaide Aqua, was undertaken by independent scientific bodies including universities and the South Australian Research and Development Institute (SARDI). The reports present conditions of the marine environment adjacent to the Adelaide desalination plant prior to operation and discharge.
The licence required further studies and reports to be undertaken over time to ascertain any changes in the marine environment. The reports are posted on the web once they are completed and received by the EPA.
n 2009, an application was submitted by Acciona Agua Adelaide Pty Ltd, McConnell Dowell Constructors Pty Ltd and Abigroup Contractors Pty Ltd (trading as AdelaideAqua) for a licence to operate the Adelaide Desalination Plant. The following prescribed activities of environmental significance were to be undertaken: discharges to marine or inland waters, and chemical storage and warehousing facilities.
This is for discharge of brine which will included some neutralised water treatment chemicals and the associated storage of water treatment chemicals at the Adelaide Desalination Plant, Chrysler Road, Lonsdale.
The EPA has imposed conditions on the licence to monitor and minimise any environmental impacts.
- Licence application
The application appendices are not available for download due to the size of the files; these are available from the EPA on request.
- Environmental performance summary report.
The public were invited to make written submissions regarding the licence application in January 2010 and submissions closed in February 2010