LECTURE NOTES For Environmental Health Students Human and Other Liquid Waste Management Kebede Faris, B.Sc., M.Sc.; Tadese Alemayehu, B.Sc.; Mamo Wubshet, B.Sc.; Dejene Hailu, B.Sc. Jimma University In collaboration with the Ethiopia Public Health Training Initiative, The Carter Center, the Ethiopia Ministry of Health, and the Ethiopia Ministry of Education November 2002 Funded under USAID Cooperative Agreement No. 663-A-00-00-0358-00. Produced in collaboration with the Ethiopia Public Health Training Initiative, The Carter Center, the Ethiopia Ministry of Health, and the Ethiopia Ministry of Education. Important Guidelines for Printing and Photocopying Limited permission is granted free of charge to print or photocopy all pages of this publication for educational, not-for-profit use by health care workers, students or faculty. All copies must retain all author credits and copyright notices included in the original document. Under no circumstances is it permissible to sell or distribute on a commercial basis, or to claim authorship of, copies of material reproduced from this publication. ©2002 by Kebede Faris, Tadese Alemayehu, Mamo Wubshet, and Dejene Hailu All rights reserved. Except as expressly provided above, no part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without written permission of the author or authors. This material is intended for educational use only by practicing health care workers or students and faculty in a health care field. Preface The protection and promotion of health, human comfort and well being through control of man’s environment are responsibilities which modern conditions have forced upon us. The population increase has demanded diversified activities, which have accompanied diversified environmental problems. This diversity creates complication where control becomes more difficult. For us such complicated problems are choking us before we even come out of the rudimentary ones. Human excreta and liquid waster problems are considered as the most important for Ethiopia. Deplorable unsanitary conditions are apparent in city slums, market areas and near restaurants and hotels. People’s sanitary practices need to be curbed to the better. It is anticipated that the amount of waste matter will increase with population increase. A waste generated and left unattended, which is the normal practice, will choke the environment and us. This lecture note, which is specifically prepared for the diploma level environmental health students, will address the problem of human waste disposal or management. Different appropriate latrine technologies and on-site wastewater containment and treatment facilities are listed; their construction methods and the advantages and disadvantages of each is included. Emphasis have been made on the new concept ecological sanitation or compost toilets as it seems timely to think of “zero waste” options especially now where population is increasing in small towns and larger cities. To think in terms of "Zero Waste" in the living environment will help in safeguarding the environment; the natural resources and the general ecosystem. The challenge now is both in the “hardware”, (the latrine technology that is appropriate and affordable) and the “software “issues which include hygiene education for behaviour change. • How should sanitation programs be organized? (see page 112- 117) • How are we getting the beneficiaries accept the technology and install the system by themselves and continue to do so thereafter? * How would we be able to change the behaviour and practices? of individuals in communities? • What type of technology is (see page 21) 1. Acceptable ? 2. Sustainable? 3. Easily operable? 4. Replicable? 5. Replaceable or maintainable? 6. Beneficial / not a liability? These are some of the questions that must be clearly answered in order to have a viable and sustainable community based sanitation and hygiene behaviour change program. In this lecture note a chapter on operation and maintenance of the sanitary installations is included. Each chapter has its own objectives, model questions, and assignment suggestion, which will help the teacher, do cognitive and summative evaluation of his students. The sanitarian trained to carry out this task must be conversant with the psychology and social make up (custom, tradition) of the community to be served, and the preferred technology to be used for that particular soil, geography, economy and tradition. What is important is that teachers of this course should help the student understand the problems and solutions so that a functional, confident and devoted professional is created. Acknowledgments The four Environmental Health schools in the country had acute shortage of teaching materials for their diploma level students. Reference materials that are prepared for foreign countries and by foreign authors have many irrelevant materials for conditions in Ethiopia. Materials that are incorporated in the books we purchase for reference materials for our students generally are based on developed country experience, technologies and policies. It is with this understanding that we are assisted by Carter Center to prepare this lecture note specifically for diploma level environmental health students. We are very grateful for Professor Carlson without whom things would have not got the green light from Carter Center. We are also indebted for the senior consultants who had been with us and gave us valuable suggestion from the outset when decision to prepare the ‘lecture notes’ was raised in Jimma. We are indebted to Ato Gebre Emanuel Teka for his valuable suggestions he made after reviewing this lecture note. His comments were so valuable that it has given our lecture notes much more shape and completeness. Las but not least we are very grateful for Ms. Carla Gale, Ato Aklilu Mulugeta and Miss Meseret Tsegaw of the RTA office who committed themselves in facilitating several workshops for our group in Addis Ababa. Contents Preface ii Acknowledgment iii Table of content iv List of figures vii List of tables viii Chapter One Introduction 1 Problems and needs 2 Ways of disease transmission from excreta 11 Life cycle for some common parasites 13 • Ascaris Lumbricoides 13 • Hookworm 14 • Tapeworm 14 • Strongyloides Steericoralis 16 • Trichuris T.ricuria 17 • Enterobious Vermecularis 18 Review Question/Assignment 19 Chapter Two Human waste management 21 Introduction 21 Barriers for sector development 22 Principle for breaking the barrier 25 Future challenges for proper sanitation development 28 Review Question/Assignment 30 Chapter Three Sanitation technologies 31 Introduction 31 Typesof technologies and construction methods 32 Drop-and-store system 35 • Pit latrine 35 • Raised pit latrine 41 • VIP latrine 42 • Alternate or double pit VIP 52 • Multiple seat VIP 51 Other Systems • Roec 53 • Aqua Privy 54 • Bucket latrine 58 • Trench latrine 58 • Overhang latrine 60 • Bore Hole Latrine 61 • Other Environmental friendly system 62 Notes to the teacher 79 Drop-And Flush System 79 • POUR-Flush latrine 79 • water carriage system 84 Review Questions 86 Chapter Four Individual containment and treatment system 87 • Introduction 87 • Cesspool 89 • Septic Tank 90 • Soak Pits 96 • Seepage Pits 98 Community Waste Treatment System 100 Waste Stabilization Ponds 107 Review Question/Assignment 111 Chapter Five Industrial Wastes 113 Introduction 113 Wastes from food industries 114 Wastes from textile mills 116 Tanner waste 119 Chapter Six Operation and maintenance for different sanitation Installation 123 Introduction 123 • Pit and VIP latrine 124 • Pour Flush 125 • Septic Tanks 126 • Cesspool 126 • Ecological sanitation 127 • Waste stabilization ponds 127 Chapter Seven Planning and programming for human waste management 132 • Introduction 132 • Essential elements 133 • Preparation of the necessary Staff 133 • Initiation of a Community sanitary survey 133 • Health/hygiene education 134 • Selection and design of units 134 • Pilot project 135 • Estimate of costs and budgets 135 • The governments role ` 135 Glossary 137 Bibliography 140 Tables Table 1 Major category of excreta related diseases and the control options 4 Table :2 Excreta related disease and their characteristics 7 Table: 3 Samples of prevalence for some common parasities and other excreata infections. 11 Table:4 Quantity and nutritional value of feces and urine 72 Table:5 Pathogen survival time in different environmental conditions 76 Table:7 Choice of sanitary system 85 Table:8 Pollutant types from cotton processing wastes 118 Figures Figure :1 Transmission routes of disease from excreata 12 Figure:2 Lif cycle of ascariasis Lumbricoids 13 Figure:3 Life cycle of Hookworm 14 Figure:4 Life cycle of Beef Tapeworm 15 Figure:5 Life cycle of Strongloides 17 Figure:6 Life cycle of Tricuris Tricuria 18 Figure:7 Life cycle of Enteobious Vermiclaris 19 Figure:8 After WSSCC working group on promotion of sanitation 29 Figure :9 Parts of pit latrine 40 Figure:10 Parts of a raised pit latrine 41 Figure:11 Part of a single VIP latrine 44 Figure:12 Type pit coves 46 Figure:13 Part of vent pipe 49 Figure:14 Dounle value latine showing part of the system 50 Figure:15 Floor plan of a multiple pit VIP 52 Figure:16 Part of reed odorless earth closet 54 Figure:17 Shape and parts of aqua privy 55 Figure:18 The Dehydrating toilet 64 Figure:19 Double vault toilet with urine diversion arrangement 65 Figure:20 The nitrogen cycle 67 Figure:21 compostng toilets 68 Figure:22 Windrow composting system 69 Figure:23 Urine diversion system 71 Figure:24 Part and layouts for ecological sanitation 78 Figure:25 Pour - flash toilet with leaching pits arrangements 83 Figure;26 Septic tank system with inlet and out let arrangement 94 Figure:27 Part of a soak pit showing grease traps 97 Figure : 28 Lay outs and parts of seepage pits 99 Figure : 29 Bar screen 102