Orange County Water District

In the 1970s, OCWD piloted Water Factory 21, the first facility in the world to successfully demonstrate that potable-grade quality recycled water can be reliably produced from treated used water effluent through an advanced water purification system relying on reverse osmosis and granular activated carbon. Since then, based on research and demonstration efforts by OCWD, a three-stage advanced treatment process of microfiltration, reverse osmosis and ultraviolet/hydrogen peroxide has been established as the standard for potable water reuse in the industry.

With Water Factory 21, OCWD established itself as the pioneer in water reuse and groundwater management. Armed with this track record, OCWD launched its most ambitious project in 2008. The Groundwater Replenishment System (GWRS) is a visionary water reuse project that reuses sewage effluent to recharge aquifers.

This project, which began producing water in January 2008, provides a new source of high­ quality water for year-round recharge to the aquifer. It is currently capable of supplying 70 mgd (or 265,000 m3/d) of water, enough to meet the needs of nearly 600,000 people. Approximately half of the advanced purified water is pumped to OCWD surface recharge facilities in Anaheim, California and the remaining water is injected into Orange County's seawater barrier for its expansion. To date, 125 billion gallons (443,000 megaliters) of water has been produced by the GWRS. In addition, the GWRS provides a water supply that is produced using half the energy required to pump water from Northern California - saving enough energy to power 21,000 homes each year.

This is increasingly important in today's climate, where sources of imported water that have historically been relied upon for recharge (such as the Colorado River and the California State Water Project) are becoming increasingly scarce. It also brings about increased water supply reliability and better utilisation of a precious resource.

To ensure a comprehensive and sound assessment of water reuse and aquifer recharge efforts, an Independent Advisory Panel was set up, comprising experts from various fields including toxicology, microbiology, hydrogeology, public health and environmental engineering. This Panel provided public confidence that critical aspects of the projects have been independently and scientifically scrutinised.

OCWD has also been instrumental in driving various policies around groundwater management, including the introduction of a fee, since the 1950s, based on volume of groundwater extraction for cost recovery and to encourage water conservation. Harvesting storm water with the cooperation of the US Army Corps of Engineers and purchasing imported water to create a buffer to periods of drought have also been important parts of the groundwater management programme by OCWD. Comprehensive monitoring of groundwater quality throughout the groundwater basin has helped to assure that OCWD's retail water agencies could reliably comply with all US and California water quality standards.

Besides being recognised as a technical leader in the field of water reuse, the comprehensive manner in which OCWD undertook public outreach and engagement to bring about public acceptance of potable water reuse is notable, and has been emulated by countries such as Australia, Singapore and many cities in the United States.

In particular, the aggressive outreach campaign to garner public acceptance for GWRS started several years before the project came on-line in 2008. From 1999 to 2007, more than 1,200 presentations about the science behind the GWRS were given to local, state and federal policymakers, business and civic leaders, health experts, environmental advocates, academia and the general public. Thousands of media impressions were secured and unanimous support for the project was received from OCWD's local, state and federal delegation.

The public outreach and public support programme implemented by OCWD for the GWRS has become the model for gaining public acceptance of new indirect potable use water projects. OCWD has been sharing its outreach system with various cities and countries to help further boost the public acceptance of this important new water supply. OCWD's public outreach programme has won the nation's highest outreach award, the Public Relations Society of America (PRSA) Silver Anvil Award in 2006 and most recently in 2013, the American Academy for Environmental Engineers and Scientists Environmental Communications Award.

Against today's backdrop of weather variability which poses major challenges for water resource management, water reuse is increasingly becoming a viable and sustainable option around the world. While many cities face some form of resistance in their water reuse efforts, OCWD has pioneered all the elements that are relevant for the successful implementation of water reuse and groundwater management, including the application of innovative water treatment technologies for treating used water, artificial groundwater recharge, groundwater monitoring, groundwater modelling, pollution prevention, water quality management and public outreach. Its successful implementation model has been replicated in the states of Texas and Colorado in the United States, and in countries such as Australia and Singapore to achieve water sustainability through water reuse, benefitting millions in the process. It is widely considered an international leader - with hundreds of engineers, scientists, officials and water experts from around the globe visiting its facilities each year. OCWD staff are also sought out by local, state, national and international agencies and governments to provide expert advice and participate in important research in numerous fields resulting in innovative technology and water projects. Its staff serve on prominent and prestigious boards and expert panels that help solve global water problems.

OCWD has greatly influenced the global water reuse market and the GWRS has become a model for groundwater recharge and water reuse schemes worldwide. It is noted that OCWD continues to evolve and continues to inspire innovation in water treatment and reuse worldwide.