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Planned Indirect Potable Reuse |
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 Planned indirect potable uses have occurred for many years - with no known health issues. Many utilities worldwide deliberately mimic Nature by recycling through technology. A few examples are:
Orange County Water District, California, USA - Since 1976 has injected treated reclaimed water into the groundwater aquifer
- Water drawn from aquifer is treated and provides drinking water for 2 million people. See the details
Upper Occoquan Sewage Authority, Virginia, USA - For 25 years has discharged recylced water to the Upper Occoquan Reservoir with NO public health issues
- Water from the reservoir is a source of drinking water for 1.2 million people. See the details
Singapore's NEWater - Since 2003 has mixzed reclaimed water with reservoir water
- NEWater currently provides 1% of the current drinking water for 4.2 million people
- 70 ML/d is provided to 50 high-tech users who demand highly purified water See the details
| Scheme | Years of Operation | Advanced Water Treatment (AWT) Process | Production/proportion of supply | Notes | | Orange County California USA | | Water Factory 21 | 1976 - 2004 | Feed water: secondary effluent
AWT: Lime clarification
Ammonia stripping
Recarbonation/filtration
Granular activated carbon
Chlorination
Reverse osmosis (1977)
Advanced oxidation (2001) | 53 ML/day
3.2% total OC water
4.8% OC groundwater | - Water injected into Talbert Gap seawater intrusion barrier to prevent saltwater ingress. Approximately 95% of injected water makes its way into the aquifer.
- Reverse osmosis added 1977.
- Ammonia stripping decommissioned after reverse osmosis added.
- Advanced oxidation (UV/hydrogen peroxide) added 2001 for NDMA removal.
| | Interim Water Factory 21 | 2004 - present | Feed water: secondary effluent
AWT: Microfiltration
Reverse osmosis
Ultraviolet/advanced oxidation | 9.7 ML/day
1% OC groundwater | Interim arrangement to maintain Talbert Gap seawater intrusion barrier during construction of Groundwater Replenishment System | | Groundwater Replenishment System | To be commissioned 2007 | Feed water: secondary effluent
AWT: Microfiltration
Reverse osmosis
Ultraviolet/advanced oxidation | 240 ML/day
18% OC groundwater | Advanced oxidation by UV/hydrogen peroxide. | | Windhoek Namibia | | Original installation | 1968 - 2002 | Feed water: secondary effluent
AWT: Algae flotation
Foam fractionation
Chemical clarification
Sand filtration
Granular activated carbon
Chlorination | 4.8 ML/day
4% | Sometimes used for direct potable reuse. | | Upgrade/expansion | 2002 - present | Feed water: secondary effluent
AWT: Pre-ozonation
Dissolved air flotation
Sand filtration
Ozonation
Granular activated carbon
Ultrafiltration
Chlorination | 21 ML/day
25% | Pre-ozonation for Fe/Mn removal | | Singapore NEWater | | | Feb 2003 - present | Feed water: clarified secondary effluent
AWT: Microfiltration
Reverse osmosis
Ultraviolet disinfection | 13.6 ML/day 1% | - Plant commissioned and Singapore Water Reclamation Study commenced May 2000.
- Total production of 3 existing plants 92 ML/day – majority supplied directly to high technology industry.
- Indirect potable reuse component to 2.5% by 2012.
| | Upper Occoquan Sewage Authority/Fairfax County | | | 1978 - present | Feed water: secondary effluent
AWT: Lime clarification
2 stage recarbonation with intermediate settling
Multiple media filtration
Granular activated carbon
Post carbon filtration
Chlorination
Dechlorination | 120 ML/day
Average 8 – 10%
Up to 90% of inflow to Upper Occoquan Reservoir under dry conditions | - Water discharged to Upper Occoquan Reservoir – major raw water source for Fairfax County.
- Capacity being expanded to 200 ML/day
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Information Sources Orange County - DDB Engineering Inc - Orange County Water District Interim Water Factory 21 and Talbert Gap Seawater Intrusion barrier 2004 Annual Report – prepared for the California Regional Water Quality Control Board, Santa Ana Region
- Orange County Water District Web Site www.ocwd.com
- Groundwater Replenishment Scheme Web Site www.gwrsystem.com
Windhoek Namibia - Ben van der Merwe, Case Study on Water Demand Management in Windhoek www.winhhoekcc.org.na/repository/Services&Procedures/Water/Case_Study_Water_Demand_1999.pdf
- Ian B Law, Potable Reuse – What are we afraid of? Proceedings Ozwater Convention, Brisbane Qld 8 – 12 May 2005.
- J Lahnsteiner and G Lempert, Water Management in Windhoek Namibia
- United States Environmental Protection Agency, Guidelines for Water Reuse EPA/625/R-04/108 September 2004
- World Health Organisation, Health risks in aquifer recharge using reclaimed water – State of the art report SDE/WSH/03.08
Singapore NEWater - H. Seah, J. Poon, G. Leslie, I.B. Law, Singapore NEWater Demonstration Project Another Milestone in Indirect Potable Reuse, Water June 2003
- Singapore Public Utilities Board Website www.pub.gov.sg
- Singapore Water Reclamation Study Expert Panel Review and Findings June 2002 www.pub.gov.sg/NEWater_files/download/review.pdf
- United States Environmental Protection Agency, Guidelines for Water Reuse EPA/625/R-04/108 September 2004
Upper Occoquan Sewage Authority/Fairfax County - ABC Southern Queensland radio interview 17/3/06 – Jeannie Bailey, Public Affairs Officer, Fairfax County
- Fairfax County Comprehensive Plan, 2003 Edition, Chesapeake bay Supplement, Adopted 11-5-2004
- www.fairfaxcounty.gov/dpz/comprehensiveplan/policyplan/chesapeakebay/waterpollution.pdf
- Ian B Law, Potable Reuse – What are we afraid of? Proceedings Ozwater Convention, Brisbane Qld 8 – 12 May 2005.
- From Wastewater to Drinking Water: An American Water Reclamation Plant, Public Works Online www.pwmag.com/articles/wastewater/reclaim.asp
United States Environmental Protection Agency, Guidelines for Water Reuse EPA/625/R-04/108 September 2004
There is also alot of incidental, unplanned potable reuse, see some of the examples we have found. |
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Supporter's Book |
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A. Marks, Toowoomba: I'm a 17 year old student, so I'm not quite old enough to vote. However, the recycled water project has really inspired me. I have chosen to support the recycled water project through a panel discussion in my English class at school. I believe that the 'no' campaign has based their arguments on emotions and fears rather than facts. Even though I won't be able to vote, I hope that I am able to influence others to consider supporting this safe, sustainable water supply. ...read more |
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Water Usage Links |
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Data and reports about Toowoomba's water consumption, water supply dam evaporation, water user by plant and other information can be found at www.toowoomba.qld.gov.au/artis. |
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