desalination option as it guides limits on extraction between the tidal limit and the limit at mangrove populations exist.
Bootawa Dam and Water Treatment Plant The Bootawa Dam and water treatment plant will continue to operate in much the same way as it does now. However, there will be a change to the operation and management in the form of a more relaxed phosphorous constraint.
footprint to mitigate further ecological impacts where possible.
Nabiac Water Supply Scheme We plan to construct the Nabiac water treatment plant which will treat water drawn from the Nabiac borefield and distribute it into the Manning supply scheme. This will add over 2,000 ML to our secure yield and will mean that water supplies are diversified by providing a second water source. The Nabiac scheme has received over $9M in federal funding under the National Stronger Regions fund. The scheme is expected to be commissioned in 2018.
Long-term solutions
Currently, we stop pumping from the Manning River when phosphorous and turbidity levels in the river go above a certain set point. The change will mean that we will lower the set point for phosphorous if the level in the dam is low. Previously, raising the wall of Bootawa Dam was investigated as an option to increase water security for the Manning scheme. It has currently been ruled as an option for now, as it is not feasible to construct while there is no back up supply (since the dam has to be almost emptied in order to construct the higher wall). Once the Nabiac scheme is implemented, we will have a back-up supply; however the Nabiac scheme will initially not have the capacity to cater for the entire Manning scheme. We may consider raising the dam wall and getting the most out of the existing Bootawa Dam, utilising this existing
IWCM Strategy 2015
Further investigations into the water solutions of Indirect Potable Reuse and Peg Leg Creek Dam will be undertaken over the next five years to better inform the long-term decision as to how best provide water security for the Manning scheme. Investigations, feasibility studies and business cases for the long-term secure yield solutions for the Manning will be undertaken, with a decision on the future direction of the Manning Water Supply Scheme to be made at the end of the five years.
Peg Leg Creek Dam The Peg Leg Creek Dam project was included in the 1999 Manning District Water Supply Augmentation Strategy prepared by NSW Public Works. The primary purpose for its inclusion was the potential for a 95%ile cease to pump rule being imposed, that is, it was included in the strategy to protect the Manning River during low flows. This went through significant community and regulator consultation in 1999. Subsequently, Peg Leg Creek dam was also
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