Appendix J - Water Supply and Wastewater Servicing Report

Lutheran Services                                                                                  Page 13 of 15
PF80 - Cooroy Care Farm
24 May 2018                                                                                   Ref. No. 2017.0616




       4.3           Supply Reliability
       The non-potable supply is unlikely to be 100% reliable under all weather conditions, and is likely
       to run short of water in very dry periods. Also, the northern dam will have a role as a water feature
       within the site landscaping, limiting its use as a water source. Nevertheless, it is understood that
       the southern dam is believed to be spring-fed, which will improve reliability. If dam water levels
       become low then landscape irrigation will need to be reduced to conserve water.


       4.4           Non-Potable Water Treatment
       It is assumed that the dam water supply will require minimal treatment to be suitable for the
       proposed uses. The only treatment recommended is in-line self-backwashing filtration to minimise
       the amount of solids in the system and to avoid blockages in irrigation systems.


       4.5           Design Details
       A possible configuration includes:
           •   Pump water from the on-site dams to a central storage tank for distribution to use areas;
           •   Provide basic treatment (in-line filtration) at the distribution pumps to protect irrigation
               systems;
           •   Distribute the water using a pumped pressure system.
       For the purposes of preliminary design, the following system configuration has been adopted. The
       proposed scheme configuration is indicated in Appendix B – Figure B2.

Table 10 Non-Potable Water Supply Configuration

 Component                                      Details
 Dam pumps                                      Single electric pump approx 1-2 L/s capacity to storage
                                                tank
 Pipelines to storage tank                      As required
 Dam water storage volume                       Approx. 50 kL (depending on irrigated area)
 Water treatment plant capacity                 In-line self-backwashing filter sized to suit distribution
                                                pump
 Distribution pumps                             Variable speed; capacity as required to supply irrigation
                                                areas and meet design irrigation zoning and scheduling
 Distribution pipelines to irrigation areas     As required