Impact of Water Management Practices in Residential Areas on Odour and Corrosion in Existing Sewer Networks By Ni Nyoman Nepi Marleni B.Sc. (Environ. Eng.); M.Sc. (Water Resources Eng.) Submitted in fulfilment of the requirements of the degree of Doctor of Philosophy College of Engineering and Science Victoria University, Australia May, 2016 Abstract ABSTRACT Urban water systems in many developed cities are mostly stressed due to increased demand from population growth and an extended period of drought. The pressure on these systems has led to a number of adaptations such as the adoption of Water Demand Management and Alternative Water Sources. These adaptations are called Water Management Practices (WMP), which include Water Demand Management, Rainwater Harvesting, Greywater Recycling, Sewer Mining, and so on. These WMP lead to an increased uptake of residential rainwater, greywater or mixed wastewater for indoor and outdoor use and thus lead to water savings due to reduced imported water to study area. Besides the well-known benefits of water saving from adoption of WMP, many studies have found that the implementation of WMP reduces wastewater flow, hence causing sewer problems such as blockages, odour and corrosion. While the impact of WMP on sewer blockages has been investigated, the effects on sewer odour and corrosion are still largely unknown. Therefore, using WMP scenario analysis, this study will investigate the impact of WMP on odour and corrosion problems in sewer networks. Some scenarios developed in this study are 1) Base case, 2) Water Demand Management, 3) Greywater reuse/recycling, 4) Rainwater Harvesting, 5) Sewer Mining and 6) Combined Water Demand Management and Alternative Water Sources called as Sustainable Practice. A residential area was selected since the adoption of WMP is mostly conducted in households. A model was developed to simulate urban wastewater systems associated with sewerage pipe networks. The results show that Rainwater Harvesting scenario of RH-B is a comparatively more effective scenario than other WMP in reducing potable water demand and causing less impact on sewer odour and corrosion. RH-B reduced the total imported water to study area by 38% and increased the hydrogen sulphide concentration in sewer pipe by 6%. For the worst impact, there were two scenarios that were classified as worst scenarios, they are scenario of Greywater Recycling of GR-BL and Sustainable Practice of WDM-GR. GR-BL only reduced the imported water by 15% while increased hydrogen sulphide concentration by 40%. On the other hand WDM-GR reduced the total imported water by 46%, while increased hydrogen sulphide concentration by 62%. Scaling up the number of households adopted WMP also increased the risk of sewer odour and corrosion. i Declaration DECLARATION I, Ni Nyoman Nepi Marleni, declare that the PhD thesis entitled ‘Impact of Water Management Practices in Residential Areas on Odour and Corrosion in Existing Sewer Networks’ is no more than 100,000 words in length including quotes and exclusive of tables, figures, appendices, bibliography, references and footnotes. This thesis contains no material that has been submitted previously, in whole or in part, for the award of any other academic degree or diploma. Except where otherwise indicated, this thesis is my own work. Signature .... Ni Nyoman Nepi Marleni May, 2016 ii Acknowledgements ACKNOWLEDGEMENTS First of all, I would like to thank Allah SWT, for the blessing and opportunity to finish my PhD study. I express deep gratitude towards my principal supervisor, Dr. Nitin Muttil, for his supervision, guidance and encouragement throughout my study at Victoria University, especially for the weekly meeting which we had throughout my thesis time. It was very helpful to maintain proper thesis direction and focus. I also want to express my special thanks to my co- supervisor Prof. Stephen Gray, for his constructive advice throughout my study. His experience in issues related to urban water management and wastewater quality have been indispensable in the evolution of this work. I would like to specially thank my associate supervisor Prof. Ashok Sharma and Prof. Stewart Burn from CSIRO for initiating the research project under Water for Healthy Country Flagship and securing funding for three years of my studentship at Victoria University. However, the most important of all is I would like to thank them for their supervision, excellent help and advice throughout this project. Last but not least, I also want to thank Grace Tjandraatmadja and Stephen Cook from CSIRO for their assistance during first days of my PhD time at CSIRO. I also want to thank all of them for their advice, suggestions and support, particularly during data collection. This study would not have been conducted without their permission to use CSIRO facilities. I acknowledge the support of my research colleagues. Particular thanks to Mary Bjerring Rasmussen who helped me collect my research data. My thanks to Dr Diane Brown for editing the thesis according to the Australian Standards for Editing Practice (in particular Standards D and E). iii Acknowledgements My appreciation to Ruth McDonell and Laura Locke from Yarra Valley Water (YVW) for their assistance and permission to use the YVW sewer catchment as well as supplying me with relevant data. My sincere thanks to Prof. Jes Vollertsen from Aalborg University for his permission to use WATS software. I am also indebted to him for his assistance and invaluable advice regarding hydrogen sulphide modeling. My sincere thanks to my friends who supported me throughout the study period—for offering your companionship in the bad times and for smiling with me in the happy times. My life will not be so colourful without your presence. Last, but not least, I thank my wonderful family as they are my source of inspiration, entertainment and they are my cheerleaders. To my mum, who always sends me her thoughts and prayers—it means a lot to me. To my husband and our three lovely children, who always give me their patience, continuous and unconditional support and love; without them this journey would be meaningless. To my big family in Indonesia, who always send me their prayers and wishes, thank you very much! iv List of Publications LIST OF PUBLICATIONS Journal articles N. Marleni, S. Gray, A. Sharma, S. Burn and N. Muttil, 2012, Impact of Water Management Practices in Residential Area on Sewer Network - A Review, Journal of Water Science & Technology, Vol. 65, No. 4, pp. 624–642. K. Park, H. Lee, S. Phelan, S. Liyanaarachchi, N. Marleni, D. Navaratna, V. Jegatheesan, L. Shu, 2014, Mitigation strategies of hydrogen sulphide emission in sewer networks - A review, Journal of International Biodeterioration & Biodegradation, Vol. 95, Part A, pp. 251 – 261. N. Marleni, K. Park, T. Lee, D. Navaratna, L Shu, V. Jegatheesan, N. Pham, A. Feliciano, 2015, A methodology for simulating hydrogen sulphide generation in sewer network using EPA SWMM, Journal Desalination and Water Treatment, Vol. 54, Issue 4-5, pp.1308 – 1317. N. Marleni, S. Gray, A. Sharma, S. Burn and N. Muttil, 2015, Impact of Water Management Practice Scenarios on Wastewater Flow and Contaminant Concentration, Journal of Environmental Management, Vol. 151, pp. 461 – 471. Sara Abdikheibari · H. Song, J. Cho, S. Kim, S. Gwon, K. Park, B. Maluleque, N. Marleni, L. Shu, V. Jegatheesan, 2016, In-situ Evaluation of Predictive Models for H2S Gas Emission and the Performance of Optimal Dosage of Suppressing Chemicals in a Laboratory-Scale Sewer, Journal of International Biodeterioration & Biodegradation, Vol. 106, pp 25 –33. Conference articles N. Marleni & N. Muttil, 2009, Modeling the Impact of High Strength Sewage on Septicity Occurrence in Existing Sewer Network, Proceedings of IEEE Science and Engineering v List of Publications Graduate Research Expo 2009, The University of Melbourne, Australia, September 25, 2009. N. Marleni, N. Muttil & S. Gray, 2009, Modelling the Impact of High Strength Sewage on Septicity Occurrence in Sewer Network, Postgraduate Research Seminar, Victoria University, November 13, 2009. G. Tjandraatmadja, S. Cook, C. Pollard, C. Sheedy, Y. Gozukara, N. Marleni C. Diaper, 2010, Sources of Priority Contaminants in Domestics Wastewater, Proceedings of Australia‘s National Water Conference and Exhibition, Ozwater‘10, Brisbane, Australia, 8– 10 March, 2010. N. Marleni, S. Gray, A. Sharma, S. Burn & N. Muttil, 2012, The Impact of Residential Source Management Strategies on Sewer Pipe - A Review, 34th IAHR World Congress - Balance and Uncertainty, 33rd Hydrology & Water Resource Symposium; 10th Hydraulics Conference, Brisbane, Australia, 26 June–1 July 2011. N. Marleni, S. Gray, A. Sharma, S. Burn & N. Muttil, 2012, Scenario Analysis of Source Management Practices: Impact on Sewerage Networks, 19th International Congress on Modeling and Simulation (MODSIM), Perth, Australia, 12–16 December 2011. N. Marleni, S. Gray, A. Sharma, S. Burn & N. Muttil, 2012, Modelling the Effects of Sewer Mining on Odour and Corrosion in Sewer System, 20th International Congress on Modeling and Simulation (MODSIM), Adelaide, Australia, 1–6 December 2013. Published reports S. Cook, G. Tjandraatmadja & N. Marleni, 2010, Impact of Source Management Strategies on Quality and Loads in Residential Wastewater - Scenario Analysis, Research Report of Water for Healthy Country Flagship, CSIRO Land & Water. Can be downloaded at: http://www.clw.csiro.au/publications/waterforahealthycountry/2010/wfhc-wastewater- contaminants-scenariomodeling.pdf