In an historic agreement in late 2019, the South Australian (SA) and Australian governments agreed to produce up to 40 GL of water from the Adelaide Desalination Plant (ADP) over the 2019-20 financial year to assist drought affected farmers in the Southern Murray Darling Basin.
This provided the backdrop for a recent webinar held by AWA’s SA Branch, which discussed: how the ADP is being used to deliver on the agreement, the impacts of the increased water production on the operation of the ADP, and how a significant increase in desalinated water volume is being managed through Adelaide’s drinking water network.
Dan Jordan, Director – Water Security, Policy and Planning at the Department for Environment and Water spoke first, providing an overview of how the ADP fits into Adelaide’s water security story, including SA’s rights under the Murray-Darling Basin Agreement for critical human needs.
Jordan also explained the one-off drought measure the Commonwealth negotiated with South Australia to fund production of up to 100 GL of water from the ADP to provide for the release of allocation volumes to Southern Basin irrigators through SA Water’s Murray licence for Adelaide.
The agreement is in two stages, with the first stage being the ‘Water for Fodder’ program, which saw the delivery of 40 GL of water in 2019-20 to grow pasture for the production of fodder and silage to irrigators in New South Wales, Victoria and SA. Proceeding to the second stage and delivering a further 60 GL of water in 2020-21 will be determined following a review by Marsden Jacobs. The review process will determine how, and for what purpose, water will be provided to irrigators, taking into account changes in drought conditions, SA’s water security and needs of irrigators.
The next speaker was Ambrose McGrath, Process Controller from Adelaide Aqua. McGrath described how the ADP operations moved from business as usual ‘Hot Standby’ production sequencing, where the plant produces water in a narrow window one or two days per week, to the ‘Water for Fodder’ high-production mode which is almost 24 hours a day, seven days a week.
This increase in production has had significant challenges, in part because of the COVID-19 pandemic, which impacted staffing arrangements and also provided challenges with chemical supply and logistics and timing for essential maintenance activities, such as seawater intake shock dosing and membrane cleaning regimes. Despite all these challenges, the ADP has been able to meet the production requirements of the ‘Water for Fodder’ program and maintain necessary water quality.
Water Systems Optimisation Engineer at SA Water Lisa Blinco provided an overview of how the ADP fits into Adelaide’s water supply mix and the impacts and limitations in distributing desalinated water to the extremities of the Adelaide metropolitan water network.
Blinco also described a Distribution Optimisation Tool that is used to predict different volumes of water produced and distributed from different sources, including the ADP, based on water availability, customer demand and network system constraints. The model indicates the ADP can supply a maximum of 84 GL in a dry year, 11 GL in a wet year and 43 GL in an average year.
A question and answer session followed which further explored the complexities of the drought response program and its impact on the ADP operation and network supply. From the comments posted during the webinar, attendees enjoyed their breakfast and found the information and discussion stimulating. They also look forward to hearing about any future role the ADP may have in trading water within the Southern Murray Darling Basin water market.
A link to the webinar recording will be available on our YouTube channel soon.