There is an option to re-use water from any treatment node that has a permanent pool volume, plus the infiltration system node, by specifying a demand:
The Max Drawdown height specifies the water level allowed for re-use, starting from the top. For example:
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- Defined as an annual demand (ML/yr) and scaled according to the daily Potential Evapotranspiration data contained in the Meteorological Template used to create the model;
- Defined as an annual demand (ML/yr) and scaled according to the daily PET value minus the daily rainfall data contained in the Meteorological Template used to create the model rainfall (i.e. when PET exceeds rainfall, reuse will occur);
- Defined as a daily demand (kL/day);
- Defined as annual demand (ML/yr) and scaled according to a user defined distribution; or
- Defined through the use of a user defined time series.
To edit the user defined distribution of the annual demand, select the 
button. The graphical editor shown below allows the user to edit the percentage of the annual demand for each month.
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To enter a user defined timer series, either type in the file path and file name, or click on the Browse button, to locate a previously prepared comma separated value (CSV) file which contains the reuse rate (in L per time-step). The re-use file must be a CSV file with a separate reuse value on each line. The time-step for the reuse file must be the same as that used in the meteorology template file. Only a single column of data should be provided in the CSV file. A header row may also be incorporated or may be left blank.
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