Access Water

By Dr. Glen Daigger, International Water Association President and CH2M HILL Senior Vice President and Chief Technology Officer

Dr. Daigger will be presenting the paper, “A Sustainable Near-Potable Quality Water Reclamation Plant for Municipal and Industrial Wastewater Begins Delivering Water,” on Wednesday, October 19, 2:30-3:00pm, in Room 303AB during WEFTEC. See a full list of CH2M HILL’s WEFTEC events and participation.

Australia is a water-short continent that is also dealing with the impacts of climate change on its water supply systems. In the search for environmental improvements, coupled with sustainable water supplies, Gippsland Water has turned to water reclamation based on membrane bioreactor (MBR) and reverse osmosis (RO) technology. The unique features of MBRs and RO formed the basis for their selection for the Gippsland Water Factory in Traralgon, Victoria, Australia. This facility was designed to process 16,000 m³/day of municipal wastewater and 19,000 m³/day of industrial (pulp and paper) wastewater from Australian Paper, to produce reclaimed water to be used as an industrial water supply and with a quality matching the pristine water source currently supplied by Gippsland Water to Australian Paper.

Reflecting differences in composition, the municipal and industrial wastewaters are treated in two separate process trains.

Municipal treatment consists of preliminary treatment, primary treatment (option to operate in an “activated” mode), MBR incorporating biological nitrogen and phosphorus removal (BNR), chlorine disinfection, and RO. BNR is provided because this wastewater contains excess nutrients, which must be removed to comply with stringent effluent nutrient requirements, even with RO following it.

Industrial treatment consists of anaerobic pretreatment, MBR treatment without BNR, with Phase 2, currently planned to be ozone, biological activated carbon, followed by RO. This industrial wastewater is high strength, nutrient deficient, and with significant residual non-biodegradable organic matter (derived from Kraft pulping activities) that can rapidly foul RO membranes.

The two process trains are linked via transfer of sludges from the domestic to industrial train. Municipal primary and municipal and industrial waste activated sludges are sent to the anaerobic treatment unit for stabilization, as a source of nutrients for the nutrient-deficient industrial wastewater, and for biogas production as an energy source. The digested biosolids are dewatered. These wastewaters posed a number of challenges which we addressed and I will share during my WEFTEC presentation.

Sustainability and “green” engineering principles were incorporated throughout the design process. Factors considered in addition to cost effectiveness included creating a sustainable water supply, minimizing greenhouse gas emissions (lifecycle analysis based accounting method), minimizing chemical usage, optimizing overall plant operability, and generating community learning and support through public education, which included building an interpretive education center at the facility. Details of how sustainability has been built into the process selection and plant design concept will also be shared in the WEFTEC presentation.

The Gippsland Water Factory was developed based on extensive bench-scale and pilot-scale testing and process analysis, based on multi-criteria analysis to develop the most sustainable solution based on currently available and developing technology.  A project alliance model was selected to deliver the Gippsland Water Factory, the construction of which is now complete.

My WEFTEC presentation will present results of the first year’s operation of the municipal train, the first 6 month’s operation of the industrial train, and lessons learned. These results demonstrate the technical feasibility of reclaiming domestic and industrial wastewater to provide a reliable, sustainable, and economic water supply to augment surface water for industrial uses. They also demonstrate the existing and evolving technologies available to develop effective and sustainable water reclamation solutions. The experiences of the development, implementation, and operation of this unique treatment plant will be valuable to owners and engineers embarking on the important track of reuse and sustainable design.

Dr. Daigger has more than 30 years of experience in wastewater treatment plant evaluation, troubleshooting, and process design. Between 1994 and 1996 he served as professor and head of the Environmental Systems Engineering Department at Clemson University. He is the author of numerous reports, articles, and conference presentations on wastewater treatment and sustainable wastewater infrastructure. His texts are used in engineering classrooms across the country. Active in the wastewater industry, Daigger is President of the International Water Association and a member of the American Society of Civil Engineers, American Water Works Association, Association of Environmental Engineering, and Water Environment Federation, as well as numerous other professional societies. He has twice received the Harrison Prescott Eddy Award from the Water Environment Federation.