The authors express their sincere appreciation to the following individuals for their help in preparing the materials of the chapter on ‘Water Cycle’ in the “Water Resources Information Portal”. Koko Liu provided able research assistance. Ella Chan prepared the visual materials on drainage basin and urban water cycle. In addition, Ella Chan, Jill Chan, and Koko Liu assisted with copyediting, translation, typesetting, and standardising the charts and figures, enhancing the overall visual quality of the Information Portal. Ella Chan, Jill Chan, and Koko Liu are project staff in the Centre for Water Technology and Policy.

Special recognition is extended to the Project Team of the Jockey Club Water Initiative on Sustainability and Engagement (JC-WISE) for granting us permission to reprint materials sourced from the Rivers@HK Database.

The authors would also like to acknowledge the constructive feedback provided by Dr. Cheng Luk Ki, Dr. May Chui, Dr. Lincoln Fok and Professor Danny Lam on earlier drafts of the Information Portal.

The Water Resources Information Portal is an integral part of a multi-year interdisciplinary project entitled “Harnessing the Power of IoT Technologies, Data Analytics, and Advanced Household Profiling Techniques to Sustain Water-conscious Behaviors and to Inform Water-sector Infrastructure Planning,” led by Professor Danny Lam. This research project (S2021.A8.034.21S) has received funding from the Strategic Public Policy Research Funding Scheme of the Chief Executive’s Policy Unit of the Government of the Hong Kong Special Administrative Region, the Philomathia Foundation and the WYNG Foundation.