A fresh look at dual reticulation

1. A fresh look at dual reticulation • June 2014

2. A fresh look at dual reticulationAn assessment of the performance and ongoing viability of dual reticulation schemes on the Gold Coast, the assessment utilises the Australian Water Recycling Centre of Excellence’s Total Economic Value Framework. • Irrigation Australia National Conference • Presented by: Kathy Baker • Executive Coordinator Integrated Water Cycle Planning • Gold Coast Water • June 2014

3. Background • Prior to 2006, GCW owned and operated its bulk water supply assets • Pimpama Coomera Waterfuture Master Plan (including Class A+ recycled water) adopted in 2004 • By 2056, Class A+ predicted to contribute 20ML out of 366ML • Millennium drought effecting South East Qld • 10 years since adoption – appropriate to review and consider the current and future costs and benefits

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6. Map… Class A+ Uses: • Outdoor – garden irrigation, car washing • Indoor - toilet flushing • Fire fighting

7. Current situation • Class A+ to 6000 properties in the Pimpama Coomera region • Use 0.5% (0.8 ML/day) City’s total water demand • 10 ML/day is supplied by Class B/C recycled water schemes • Class A+ usage rate much less then expected • Only 8 ML/day expected in 50 years (2.4%)

8. Key changes since adoption

9. Issues • Cross-connections – complicated pipework on-lot and off-lot • Household audits

10. Value and viability assessments • Not financially viable - cancelled future expansion of DR into the Stapylton, Yatala and Cabbage Tree Point areas • Detailed Value Assessment of Pimpama Coomera • Total economic value of recycling – financial, environmental and social factors • Australian Water Recycling Centre of Excellence

11. End of dual reticulation for City of Gold Coast • Council resolved in December 2013 to discontinue implementation of dual reticulation on the Gold Coast due to: • High cost of operating and maintaining the scheme • High cost of constructing new capital infrastructure • Low demand usage • Negative net “value” (costs outweigh benefits) • Significant regulatory monitoring and reporting requirements • Risk of cross connections • Estimated to save rate payers $3 million/year or $114 million over 40 years (in 2013 dollars)

12. Transition Plan to decommission Class A+ supply • Potable water to be supplied via both potable and recycled water networks • Initially operated as discreet systems (no mixing) • Class C return main from Pimpama STP to Coombabah STP • ‘Switch over’ estimated to occur by December 2016

13. Existing Recycled Water Scheme • Existing Recycled Water Scheme • Northern Supply Scheme • Southern Supply Scheme • Class B/C • Approximately 50 fixed customers • Some 400 Recycled Water Carrier Customers • Total reuse for the past 5 years ranges from 16.5% - 20.3% • Total irrigated area approximately 1700ha • Irrigation of Sporting Fields, Council owned Parks, Schools, Nurseries, STP wash-down, Municipal Irrigation and Industrial / Commercial Use

14. Where to from here? • Release • Seaway • Ocean? • Local Opportunities • - Identified further open space irrigation • Additional treatment Class C to Class A+ • - Jupiter’s Casino • - Potential Commonwealth Games venues

15. Where to from here? • Potential Northern Recycled Water Scheme

16. PO Box 5042 Gold Coast MC QLD 9729 P 1300 GOLDCOAST E mail@goldcoast.qld.gov.au W cityofgoldcoast.com.au