Tendai H Madzaramba
Total Page:16
File Type:pdf, Size:1020Kb
Master Thesis TVVR 19/5003 Onsite greywater treatment for reuse at Zandspruit informal settlement in Johannesburg ________________________________________ Tendai H Madzaramba Division of Water Resources Engineering Department of Building and Environmental Technology Lund University Onsite greywater treatment for reuse at Zandspruit informal settlement in Johannesburg By: Tendai Hardwork Madzaramba Master Thesis Division of Water Resources Engineering Department of Building & Environmental Technology Lund University Box 118 221 00 Lund, Sweden Water Resources Engineering TVVR-19/5003 ISSN 1101-9824 Lund 2019 www.tvrl.lth.se Master Thesis Division of Water Resources Engineering Department of Building & Environmental Technology Lund University Box 118 221 00 Lund, Sweden English title: Onsite greywater treatment for reuse at Zandspruit informal settlement in Johannesburg Author: Tendai Hardwork Madzaramba Supervisor: Miklas Scholz Examiner: Kamshat Tussupova Language English Year: 2019 Keywords: Greywater generation, greywater treatment, greywater reuse, wastewater reuse, informal settlements ii iii Acknowledgements This research has been produced during my scholarship period at Lund University, funded by the Svenska Institutet through the Swedish Institute Study Scholarships (SISS) in Category 1 for studies within Master's programme in Water Resources Engineering. I am also grateful to the Swedish International Centre for Local Democracy (ICLD) for the grant to conduct fieldwork at Zandspruit informal settlement in Johannesburg South Africa. I would like to extend my appreciation to Professor Miklas Scholz my Academic Supervisor and Guide throughout the course of this degree project. His assistance and encouragement is priceless. Besides, l will forever cherish the opportunity l had to conduct my fieldwork abroad under his watch. I do wish to thank my Examiner Dr Kamshat Tussupova for her precious time. I would also like to thank my External Supervisor Sam Van Staden and the Department of Civil Engineering Science at University of Johannesburg for taking me in. The experience was quite fascinating. I am also thankful to my friends and family for their continuous support through the perilous journey of academic life. Finally, Glory be to God Almighty my Creator and Keeper who makes all things possible. Indeed, the steps of the righteous are ordered by the Lord. iv v Abstract The urban landscape in South Africa is marred by informal settlements. Nearly a quarter of its population lives in shacks and do not have access to sufficient clean water and improved sanitation. The aim of the present study was to ascertain household daily water consumption and quantify the amount of greywater generated at Zandspruit slums. Another objective was to assess perceptions and user acceptability towards treated greywater reuse in urban slums. Overly, the study endeavour to elucidate the potential benefits of greywater reuse in informal settlements. The author used a systematic literature review and administered a survey questionnaire to fulfil these objectives. The survey was conducted between the 1st of February and the 29th of March 2019. Zandspruit settlement has the capacity to produce significant amount of greywater for reuse. Observed daily water consumption varies from 40 – 400 L/du.d. With a mean return factor of 0.62 a medium-sized family will produce an average of 121 litres per day. 83% of the residents accept reuse of treated greywater for non-potable purposes. A further 69% expressed willingness to reuse treated greywater for drinking and cooking. The implementation of onsite greywater treatment and reuse will certainly unlock socioeconomic benefits and enhance water availability to some of the poorest people in South Africa. vi vii Table of Contents Acknowledgements ......................................................................................... iv Abstract ........................................................................................................... vi List of Tables ................................................................................................... xi List of Figures ............................................................................................... xii Acronyms ...................................................................................................... xiv 1. Background .............................................................................................. 1 1.1 Problem formulation .......................................................................... 3 1.2 Research objectives ........................................................................... 4 1.3 Relevance of study ............................................................................. 4 1.4 Limitations ......................................................................................... 5 1.5 Study area .......................................................................................... 5 1.6 Procedure ........................................................................................... 6 1.7 Adjustment of work plan ................................................................... 7 1.8 Definition of terms ............................................................................. 7 2. Greywater perspectives ............................................................................ 9 2.1 Domestic greywater generation ............................................................ 10 2.1.1 Greywater generation in informal settlements of South Africa. ... 11 2.2 Greywater characteristics ................................................................ 11 2.3 Greywater reuse regulations ............................................................ 13 2.3.1 International standards and guidelines ..................................... 13 2.3.2 South Africa greywater regulations .......................................... 14 2.4 Implications of onsite greywater reuse ............................................ 15 2.4.1 Water-use demand .................................................................... 15 2.4.2 Social acceptability .................................................................. 16 2.4.3 Public health impact ................................................................. 18 2.4.4 Environmental risk ................................................................... 19 3. Greywater treatment in informal settlements ......................................... 21 viii 3.1 Greywater treatment process ................................................................ 23 3.1.1 Physical treatment ......................................................................... 23 3.1.2 Biological treatment ...................................................................... 25 3.1.3 Chemical treatment ....................................................................... 26 3.1.4 Post treatment ................................................................................ 28 4. Materials and Methodology ................................................................... 31 4.1 Literature study .................................................................................... 31 4.1.1 Review ........................................................................................... 31 4.1.2 Structure of the questionnaire........................................................ 32 4.2 Fieldwork ......................................................................................... 32 4.3 Data Analysis ................................................................................... 34 5. Results and Discussion ........................................................................... 35 5.1 Greywater generation in informal slums of South Africa. ................... 35 5.1.1 National context ............................................................................ 35 5.1.2 Greywater generation in urban slums of Gauteng Province ......... 37 5.2 Findings: Zandspruit case study ...................................................... 43 5.2.1 Housing ......................................................................................... 43 5.2.2 Demographic information ............................................................. 44 5.2.3 Overview of water supply and sanitation ...................................... 49 5.2.4 Water availability, adequacy and reliability .................................. 52 5.2.5 Water consumption and greywater generation at Zandspruit ........ 53 5.2.6 Greywater acceptability at Zandspruit informal settlement .......... 60 5.3 Discussion ............................................................................................ 63 5.3.1 Potential for greywater generation at Zandspruit. ......................... 63 5.3.2 Greywater reuse: User perceptions and acceptability. .................. 65 5.3.3 Socioeconomic impact of onsite greywater treatment and reuse. 69 5.3.4 Feasibility of onsite greywater treatment in slums. ....................... 70 6. Conclusion .............................................................................................. 73 ix 7. Recommendations .................................................................................. 75 8. References .............................................................................................. 76 9. Appendices ............................................................................................. 93 9.1 Appendix 1: Popular science summary ...............................................