What is the timeline to deliver this project

    Construction is expected to start on the new trunk main pipeline in September 2021.

    The desalination plant will take between 18 and 24 months to complete with operations estimated to commence in 2022.

    Where will the new desalination plant be located?

    The new desalination plant will be located near the Hog Bay Road - William Walkers Way intersection, within the road reserve area. This is our preferred site due to:

    • It is the furthest site from the closest neighbours
    • It is Council owned land - care and control by DIT - giving us the best opportunity to meet project and funding timeline requirements
    • utilisation of existing vegetation on the south western side

    What is a trunk main?

    The pipeline connecting the new desalination plant to the Middle River-Kingscote network is likely to be a trunk main, which is typically constructed to transport bulk quantities of water from one location to another.

    Trunk mains are not generally part of the reticulation network that connects directly to customers. 

    This new trunk main will hold sufficient capacity to develop new reticulation networks to service residents in Baudin Beach, Island Beach, Sapphiretown and American River as well as direct connections off of the new trunk main. 

    How much water will the new desalination plant produce?

    The new desalination plant will be able to produce 2 megalitres (ML) per day (approximately 700 ML/year) with supporting infrastructure sized, including the new pipeline, for the ultimate long-term Plan capacity of 6ML per day should demand require an increased capacity in the future.

    What is the current demand for water on Kangaroo Island

    SA Water operates two water supply systems on Kangaroo Island. One provides water to Kingscote, Brownlow, Parndana and surrounding rural areas from the Middle River Reservoir. 

    The other supplies the township of Penneshaw from a desalination plant. The current demand on the Middle River system is 356 megalitres (ML) per year, with demand varying from 18-20ML per month during winter, to 50-65ML per month during summer.

    The current demand on the desalination plant at Penneshaw is 52ML per year. Over the last three years, peak demand has reached 400 kilolitres (kL) per day. Low demand periods are around 86 to 172kL per day.

    Can I apply for a connection?

    Land owners along the trunk main route can lodge an application for a new connection here

    We will continue to work with owners of properties in American River, Baudin Beach, Sapphiretown and Island Beach as we develop the design of the reticulation mains in these communities. Connection applications for these property owners will be made available soon.

    How does a desalination plant work?

    Our desalination plants use a technology called reverse osmosis. The process removes up to 99 per cent of the impurities and salt in the water.

    Once the impurities (mainly salt) are removed, the water is treated to ensure it is safe to drink.

    What experience does SA Water have with operating desalination plants?

    We operate nine desalination plants across South Australia including seawater desalination plants at Lonsdale in Adelaide and the existing plant at Penneshaw.

    Our desalination plants improve security of drinking water supplies for our customers. They give us the ability to supply water regardless of climate impacts and ensure drinking water is still available even in times of drought.

    Do I have to connect to the new reticulation main in my community?

    New standard connections will be optional for property owners however rating on abuttal fee of $274.40 per year (2021-22) will apply. 

    Over the course of this project, we will engage with members of Baudin Beach, Island Beach, Sapphiretown and American River on opportunities and interest in connecting to a new, safe, secure, affordable drinking water network.

    What percentage of the Island's water usage is new desal plant expected to produce?

    The new desalination plant will produce as much as 80% of the Island’s current water requirements. 

    This will allow for growth and an expected increase in demand by 2022 due to new development. If all the forecast growth is realised, then the new plant would deliver around 50% of the Island’s water supply.

    What happens to the salt once it is extracted at the Penneshaw desal plant, now and also in the expanded version?

    The saline discharge is returned to the ocean. Past studies have shown that with proper engineering measures in place, the saline discharge is rapidly diluted.

    Additionally, monitoring has shown that there have been no discernible changes to the marine environment living around the existing Penneshaw outfall pipe since operation.

    All relevant planning and environmental approvals and licenses will be sought for the new desalination plant.

    What is the annual energy consumption in kilowatt hours of the existing Penneshaw desalination plant and how much energy is the new plant expected to use?

    In the 2019/2020 financial year, the existing Penneshaw plant used approximately 400-Megawatt hours to produce and pump 80 ML water to our storage site and to our Penneshaw customers.

    The operation of the new desalination plant is expected to require approximately 3,400-Megawatt hours each year to produce and pump as much as 700ML of water per year across the Island.

    Part of the scope of the project will include investigations into alternative renewable energy options that would minimise our demand on the Islands power supply, enhance the sustainability of the new plant and reduce the cost of operating the plant and its supporting infrastructure.