Orange County Sanitation District Receives 2012 NWRI Award of Excellence for Secondary Treatment Program

The National Water Research Institute (NWRI) of Fountain Valley, California, honored the Orange County Sanitation District (OCSD) as the fifth recipient of the NWRI Award of Excellence for the successful completion of its 10-year Secondary Treatment Program.

The NWRI Award of Excellence was established in 2002 to recognize projects that demonstrate leadership and commitment to improve water supplies, protect public health and the environment, and enhance the value of water.

Located in Fountain Valley, California, OCSD is responsible for collecting, treating, and recycling wastewater generated by 2.5-million people living in central and northwest Orange County, California.  OCSD also partners with the Orange County Water District on the world’s largest indirect potable reuse project – called the Groundwater Replenishment System – to purify and reuse treated wastewater to near-distilled quality to provide a reliable source of local water supplies for communities in Orange County.

The wastewater treatment process involves removing contaminants from municipal, commercial, and industrial sewage, as well as from runoff captured in the wastewater collection system.  Secondary wastewater treatment is the second stage of treatment, and involves the use of biological treatment processes to remove contaminants and/or bacteria.  It can remove up to 90 percent of organic matter from wastewater.

Over 10 years ago, leadership at OCSD made the decision to move to 100-percent secondary treatment (a special provision of the Clean Water Act allowed the district to treat water at a level less than full secondary treatment).  OCSD invested in secondary treatment to ensure the highest quality water is released into the ocean and provided to the Groundwater Replenishment System.  To do so, OCSD would have to complete four construction projects that would cost hundreds of millions of dollars by December 31, 2012.

The first project consisted of the construction of two new trickling filters, two clarifiers, a new power building, and two effluent lines – all were built 29 days ahead of schedule.  The second project consisted of the rehabilitation of the activated sludge plant, which was completed 290 days ahead of schedule.  The third project consisted of the construction of the trickling filters at Plant No. 2 (the largest facility of its kind in the U.S. and second largest in the world).  It consisted of three trickling filters, six clarifiers, a pump station, solids contact station, piping, and electrical controls.  It cost $180 million to construct, and was completed 64 days ahead of schedule.  The fourth projected included the construction of six aeration basins, six clarifiers, a blower building, and a return sludge and waste pumping station over 12 acres of land.  The civil, structural, and mechanical work for this project took over 370,000 labor hours over a course of 4 years, and was completed 115 days ahead of schedule.

The NWRI Award of Excellence was presented to OCSD on Friday, November 2, 2012, at the NWRI Clarke Prize Conference on “Urban Water Sustainability” in Newport Beach, California.  It was accepted by the OCSD General Manager Jim Ruth and Assistant General Manager Bob Ghirelli.

“We are honored to be the recipients of this year’s NWRI Award of Excellence,” said OCSD General Manager Jim Ruth.  “At OCSD, we take our responsibility to protect the environment very seriously and are very proud of our accomplishment.  In 2002, we made a promise to the taxpayers of Orange County and – 10 years later – we kept our promise by completing our Full Secondary Treatment program on time and on budget.  We’ve invested in Orange County’s future – a future of clean beaches and locally controlled drinking water – and ensured that generations to come will enjoy this great place we all call home.”

Over 100 people from the water and wastewater industries attended the conference, which was sponsored by NWRI’s water and wastewater utility member agencies and corporate partners.

Past recipients of the NWRI Award of Excellence include the Public Utilities Board in Singapore for their pioneering research with membrane technology to create a new source of potable water called NEWater (2002), the Honolulu Board of Water Supply for their efforts in using an innovative new technology called membrane bioreactors to enhance their water resources (2004), the Orange County Water District and OCSD for co-developing the Groundwater Replenishment System (2006), and West Basin Municipal Water District for contributions to ocean water desalination research and dedication to create a new, locally controlled sustainable water supply (2010).

More about the NWRI Award of Excellence can be found at

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