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Introductory Guide to Appropriate Solutions for

1. UNEP Technical Publication Series 8 www unep or jp ietc publications techpublications techpub 8a index as Waterlines 1993 Technical brief no 36 Ferrocement water tanks Vol 11 no 4 April 1993 Waterlines 1995 Technical Brief No 43 Simple drilling methods Vol 13 No 3 January 1995 Waterlines 1998 Technical brief no 56 Buried and semi submerged tanks Vol 16 no 4 April 1998 Wiseman K and Eberhard A A 1987 A technical economic and social analysis of alternative water pumping technologies for underdeveloped rural areas A report prepared for the Foundation for Research Development by Energy Research Institute U niversity of Cape Town 96 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water Research Commission 1998 Quality of Domestic Water Supplies 5 volumes published by the Water Research Commission WRC Volume 1 Assessment Guide WRC no TT 101 98 Volume 2 Sampling Guide WRC no TT 117 99 Volume 3 Analysis Guide WRC no TT 129 00 Volume 4 Treatment Guide WRC no TT181 02 Volume 5 Management Guide WRC no TT 162 01 9th International Rainwater Catchment Systems Association Conference Proceedings www emg warwich ac uk irdsa 9th html SOURCES OF POWER FOR PUMP SYSTEMS Baumann E 2000 Series of manuals on drinking water supply volume 7 Water lifting SKAT Switzerland Davis M Borchers M Dickson B and Geerdts P 1994 Institutions
2. The soakaway Vacuum tankers and The treatment works OO gt O peration and maintenance The soak away needs to function effectively No surface seepage should be evident The tank must be emptied and the contents transported to the treatment works Further payment for use of the treatment works is required 60 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Advantages of septic tanks Advantages include e High levels of comfort and convenience and The user does not have to handle waste Limitations of septic tanks Limitations include e There is increased susceptibility to overload during peak periods Soils must be permeable so that the effluent drains away e Provision must be made for sludge treatment and disposal and e Care must be taken not to flush objects such as sanitary towels and condoms down the toilet as these cause the tank to fill rapidly Practical experience This sanitation option is used extensively in rural and peri urban areas throughout South Africa It is used in both agricultural areas and urban settlements with large plots Key references De Villiers D C 1987 Septic Tank Systems BOU 98 CSIR DWAF Sanitation Support 2001 Study Report on Management of Faecal Waste from On site Sanitation Systems in South Africa DWAF 2002 Sanitation for a Healthy Nation Sanitation Technology Options 61 Introduct
3. provide water services to other water services institutions within its service area Water pollution Defined by the National Water Act 1998 as the direct or indirect alteration of the physical chemical or biological properties of a water resource so as to make it a Less fit for any beneficial purpose for which it may reasonably be expected to be used or b Harmful or potentially harmful i to the welfare health or safety of human beings ii to any aquatic or non aquatic organisms iii to the resource quality or iv to property Water services Defined in the Water Services Act 1997 as covering both water supply and sanitation Water Services Authority W SA Municipality responsible for ensuring access to water services Water Services Act 1997 Water services institution These include Water Services Authorities Water Services Providers water boards and water services intermediaries Water Services Act 1997 Water services intermediary An institution or individual who provides water to consumers but whose primary function is not water services provision For example a farmer who provides water to staff as part of a contract of employment is a water services intermediary Water Services Act 1997 Water Services Provider W SP Any institution that is appointed by a Water Services Authority to provide water services to consumers or to another water services institution Water Services Act 1997 Water table
4. Groundwater systems include both aquifers that are unconfined shallow and relatively accessible and aquifers that require considerable effort and subsequent management to extract water Whether shallow or deep systems dominate and whether porous or fractured aquifer systems are present yield depends on the geological geomorphological and past climate regimes of an area Springs may arise due to both shallow and relatively deep subsurface flow systems It is critical that these underground water supplies are recharged Recharge occurs naturally through the infiltration of water into the soil and underlying strata or by artificial recharge Artificial recharge is a method of replenishing groundwater resources by increasing the rate of infiltration by ponding on the surface or by injecting water down boreholes Atmospheric water resources sources Atmospheric water resources are obtained through the harvesting of both rainwater and cloud mist Rainwater harvesting involves the interception and storage of rain before water is lost to runoff and infiltration processes Cloud mist harvesting involves the interception of mist or fog with a fabric mesh or sheet and the collection of water droplets into a storage tank The additional water gathered in this manner is generally small It supplements other surface or groundwater sources Household management of rainwater occurs when collection is from roofs whilst municipal management occ
5. Thus the type of water to be pumped must be specified when a pump is selected Some pumps use mechanical seals that do not need frequent maintenance but are more expensive Others use gland packing which is cheap but requires more frequent attention and technical understanding Note that it is normal to see a slow dripping of water between the pump shaft and the gland packing If there is no dripping the shaft will not be adequately lubricated and will damage the pump set up 86 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Types of Hand Pumps There are a number of different types of hand pumps Rotor Stator Positive Displacement Systems These are the most common hand pump installations in South Africa The pumps used are MONO T5 and T7 Orbit and Cemo pumps The discharge rates are lower than with direct drive systems and the energy and power required to lift water are greater Considerable power is required to lift 25 litres of water from depths of 80 to 90 metres This can make the system difficult to operate for children and for older members of the community Reciprocating W heel Pumps About 40 years ago the climax pump was the most commonly used but this is no longer the case The large wheel and long handle provide good leverage so that large quantities of water can be pumped easily The height of the system can sometimes make it difficult for children to operate It can operate eff
6. and Immelmann E 1994 The development of fixed and dynamic membrane systems for the treatment of brackish water and effluents WRC Report no 219 1 94 Sanderson R D Vreugde M and Schoeman D W Provision of point source water by enhanced solar distillation WRC Report no 468 1 94 Schoeman J J and Steyn A 2000 Defluoridation denitrification and desalination of water using ion exchange and reverse osmosis technology WRC Report no TT 124 00 Skinner B and Shaw R 1998 Household water treatment 1 In Waterlines Vol 17 No 2 October 1998 Skinner B and Shaw R 1999 Household water treatment 2 In Waterlines Vol 17 No 3 January 1999 Visscher J T and Veenstra S 1989 Slow Sand Filtration Manual for Caretakers Training Series No 1 IRC International Water and Sanitation Centre The Hague The Netherlands Wegelin M 1996 Surface Water Treatment by Roughing Filters A design construction and Operation manual Sandec Report No 2 96 SKAT Swiss Centre for Development Cooperation in Technology and M anagement 99 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Glossary and definitions Aquifer Defined by the National Water Act 1998 as a geological formation which has structures or textures that hold water or permit appreciable water movement through them Ambient groundwater quality Background water quality It reflects the groundwater quality of th
7. Applying the manual break during storms A trained community member can do routine maintenance Advantages of wind powered pumps Advantages include These pumps can lift water from great depths and The energy source is free and renewable Limitations of wind powered pumps The limitations include Wind pumps have a high initial cost and require regular maintenance and Breakdowns can be caused in a number of ways These include rotor failure caused by high winds transmission system failure caused at the wind pump head and piston cylinder failure caused due to the borehole running dry Wind pumps do not stop unless brakes are applied Practical experience Wind powered pumps are used across the world They are widely used by the farming community in South Africa particularly in U mtata KwaZulu Natal the Free State and the Northern Cape 45 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Key reference Baumann E 2000 Series of manuals on drinking water supply volume 7 Water lifting SKAT Switzerland 46 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation W Diesel Powered Pumps W hat is a diesel powered pump and how does it work A diesel engine transmits power through V belts gearboxes or shafts to a pump Diesel pump requirements There are a number of requirements A storage tank is required for periods wh
8. The breakdown of waste material in this system is through a process known as anaerobic digestion Ventilated improved pit toilet requirements The pit must be protected so as to prevent ingress of stormwater Provision must be made either for the mechanical emptying of the pit and transportation of the sludge to the treatment works or for the toilet to be moved when the pit is full 68 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Groundwater and the system The bottom of the pit needs to be more than one metre above the water table to prevent contamination Water requirements This toilet does not require water for effective functioning Greywater This toilet cannot accept large amounts of greywater Greywater must be disposed of in a soakaway or used for garden irrigation Level of comfort This toilet cannot be placed inside a house Further the draught caused by the ventilation through the toilet to remove smells can be unpleasant to the user in cold weather Insitutional support No institutional support is required if the toilet is moved by placing it over a new pit The old pit is then covered and its contents allowed to decompose naturally However institutional support is required if mechanical emptying of pits sludge transfer treatment and disposal and cost recovery services are provided Capital requirements Capital costs include Building an outside structure The ped
9. The surface of a groundwater body at which the water pressure equals atmospheric pressure i e the uppermost level of the groundwater body beneath the land surface Water User Association WU A An association of water users for example farmers who share a common water resource 101 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation
10. Treament Works Flush Toilet with Conservancy Tank Flush Toilet with Septic Tank and Soakaway Alternating Twin Pit Composting Toilet Fossa Alterna Urine Diversion Dehydrating Toilet Ventilated Improved Pit Toilet 51 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Introduction The focus of this section is to unpack what is required for a sanitation system to function optimally The purpose is to look at the entire sanitation cycle starting with the excreta dropping into the pedestal and ending with the treated effluent or solid waste being discharged into the environment It covers both on site i e household owned and off site i e municipal owned components as well as the materials needed on site to enable the technology to function for example water for waterborne sewage It covers the issues surrounding the structure required to house the toilet The critical question is Does the toilet need to be positioned in a separate outside building or can it be incorporated into the house This is important when comparing waterborne with on site technologies Finally this section focuses on the issue of greywater treatment This is a topic that is often neglected as uncontrolled discharge of greywater can have serious problems particularly in an urban environment 52 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Sanitation Technologies W Flu
11. addition of a disinfectant such as chlorine 93 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation UV Treatment An Ultra Violet UV light is used to disinfect water UV lamps can be placed in water pipes ensuring that the water passing through these pipes receive a fixed average dose Lamps can also be mounted above shallow tanks through which the water is passed References Department of Water Affairs and Forestry have published the South African Water Quality Guidelines 1996 for both Fresh and Coastal M arine Waters See www dwaf gov za or go to your nearest regional DWAF office The following five volumes on Water Quality are available from the Water Research Commission Quality of Domestic Water Supplies Volume 1 Assessment Guide WRC no TT 101 98 Volume 2 Sampling Guide WRC no TT 117 99 Volume 3 Analysis Guide WRC no TT 129 00 Volume 4 Treatment Guide WRC no TT181 02 Volume 5 Management Guide WRC no TT 162 01 94 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation 6 ADDITIONAL REFERENCES WATER SUPPLY TECHNOLOGIES Alcock PG 1987 Domestic Water supplies in non urban KwaZulu N atal existing water systems Occasional Publication No 8 Department of Crop Science University of N atal Pietermaritzburg Ball P and Carter R 2000 Specification and drawings for the pounder rig Report of DFID KAR Project R7126 Priv
12. and biological reduction denitrification The presence of high levels of nitrate in water can be of risk to babies Ozone Treatment Ozone is produced on site by passing a current of dry filtered air between two electrodes subjected to an alternating voltage The ozone acts as a disinfectant and an oxidant that reduces the contents of iron manganese and lead It can also eliminate taste and odour problems Reverse O smosis Fresher water can be produced by forcing water with a high content of total dissolved solids under pressure through a special membrane The dissolved solids are rejected by the membrane and they stay behind while pure water goes through the membrane Reverse osmosis can be used for the treatment of water with high concentrations of nitrate nitrite potassium sodium sulphate chloride fluoride and TDS Sedimentation Sedimentation is a process where water is allowed to stand for a period of time Suspended solids settle at the bottom of the container through gravity Treatment of Encrustation Biofouling of Boreholes If borehole water is tinted brown and smells of rotten eggs it is an indication that it has been infected by either metal encrustation or bacteria or both Treatment can begin by using mechanical tools to clean easy to reach places This can be followed by chemical treatment that uses acids to dissolve precipitations The well should then be cleaned out by jetting airlifting or bailing followed by the
13. and financing for effective dissemination of PV systems for rural development Department of Mineral and Energy Affairs prepared by Energy for Development Research Centre Energy Research Institute U niversity of Cape Town Morgan P 1990 Rural Water Supplies and Sanitation A text from Zimbabwe s Blair Research Laboratory Harare Macmillan Education Ltd Omar I and Law S 1992 Energy alternatives for the supply of water in Namaqualand National Energy Council Pearson L A Bhagwan J Kariuki W and Banda W 2002 Guidelines on Appropriate Technologies for Water Supply and Sanitation in Developing Communities WRC report no 520 1 01 Sami K and Murray E C 1998 Guidelines for the evaluation of water resources for rural development with an emphasis on groundwater Water Research Commission report no 677 1 98 Smet J and van Wijk C 2002 Small Community Water Supplies Technology people and partnership IRC technical paper series 20 Stasikowski A W and van Rensburg P 1998 Low cost air lift groundwater pump developed for use in rural settlements Water Research Commission Report no 876 1 98 UNEP 2000 Sourcebook of alternative technologies for freshwater augmentation in Africa UNEP Technical Publication Series 8 www unep or jp ietc publications techpublications techpub 8a index asp 97 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Wiseman K and Eberhard
14. and motor from fault conditions such as Pumping without water e Pumping against a closed valve causing over pressurisation Overload caused by conditions such as a blocked inlet a blocked outlet a jammed pump or by bearing failure in the pump or motor and e Faults with the electrical supply such as phase failure phase rotation and voltage out of range Surge arrestors and other forms of lightning protection are also required to provide some protection against lightning damage However if lightning strikes the pump house directly no amount of protection will save the installation Some electric motors are enclosed in waterproof housings with sealed shafts to enable them to operate under water Such pumps are termed submersible and are used for example in the smaller borehole pumping installations typically less than 5 kilowatt applications There are two main classes of pumps Centrifugal pumps A centrifugal pump consists of one or more impellors similar to a boat propeller each of which rotates within its own housing When there is only one impellor the pump is called a single stage pump When there are several impellors the pump is called a multi stage pump With higher pumping heads more stages are added and the power requirement increases Any centrifugal pump has a maximum pressure rating with a given motor and drive setup and cannot lift water above that pressure level If there is a problem with the pipeline
15. are used widely in Namibia and a smaller number in South Africa and Zimbabwe 22 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Key references Clanahan M J 1997 Sand Abstraction Systems Proceedings of the 23rd WEDC Conference Durban Loughborough U niversity Hussey S W 1997 Small scale Sand Abstraction Systems Proceedings of the 23rd WEDC Conference Durban Loughborough U niversity Hussey S W 1999 Acceptability utilisation of sand abstraction water supplies 25th WEDC Conference Ethiopia Wipplinger O 1958 The storage of water in sand South West Africa Administration Water Affairs Branch Burger SW and Beaumont RD 1970 Sand Storage dams for water conservation Proceedings of the Water year 1970 Convention Pretoria 23 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation W Artificial Recharge _ ae oe ee eS eee Qa a y Recharge dam EA p i r me rg Fa ei w i per mae a SS Water seeps into underlying strata Fractured rock aquifer Water fed down borehole W hat is artificial recharge and how does it work Artificial recharge is used to increase the yield of groundwater by increasing the rate of infiltration or by direct replenishment Surface water is either led to infiltration basins where it is allowed to stand and seep into the ground or water is fed directly down a borehole i
16. can accept greywater However if significant quantities are disposed of tanks will need to be emptied more frequently This may be as often as once every week depending on the size of the tank Level of comfort The toilet can be located inside the house A water trap prevents smells from the sewage entering the toilet Also this system prevents uncomfortable draughts whilst using the toilet Insitutional support Institutional support is required for Emptying of tanks and the transportation of sewage to the treatment works Establishment as well as operation and maintenance of the treatment works The billing associated with the use of the treatment works and the collection of the sewage by tanker and Effective credit control Capital requirements Capital costs include The on site piped water supply The toilet structure this cost can be reduced if the toilet is placed inside an existing house The cistern The pedestal The tank Vacuum tankers and The treatment works gt gt O peration and maintenance O peration and maintenance requires the following The seal in the cistern requires replacement from time to time Rodding of on site pipes is necessary to clear blockages and The tank must be emptied and the contents transported to the treatment works 57 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Advantages of conservancy tanks Adv
17. e Solar panels The DC AC converter and batteries if required The electric pump and The storage tank 41 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation O peration and maintenance Maintenance generally involves keeping the panels free from dust and dirt and protecting them from animal and human damage Advantages of solar powered pumps Advantages include Solar powered systems like diesel systems are generally reliable robust and do not require regular maintenance The energy source used is free and renewable and Solar energy is an attractive option for remote areas where fuel is expensive and difficult to find and grid electricity does not exist Limitations of solar powered pumps The limitations include e Photovoltaic panels use advanced technology and have to be imported When problems occur with solar pumps even simple electrical faults specialists have to be called in at great expense Solar panels are prone to theft e Each panel can produce only a limited amount of electricity per day for example 250 watt hours depending on the weather and e Photovoltaic systems are only cost effective where relatively low volumes of water are being pumped per day at relatively low heads for example up to 20 metres cubed per day to 40 metres head Practical experience Solar powered pumps are used mainly on private farms and game reserves as a substitute for di
18. not dependant on a single manufacture or supplier Advantages of hand pumps The advantages of hand pumps include the fact that they use a free energy source namely human power Limitations of hand pumps Limitations include the fact that hand pumps are not suitable to lift groundwater from depths greater than 45 metres since human power is required to lift the column of water However if the pump is geared it can be effective up to a depth of 90 meters but it still require a huge effort for a minimal amount of water Practical experience The number of hand pumps in operation in South Africa is estimated at between 10 000 and 15 000 39 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Key references Arlosoroff S Tschannerl G Grey D Journey W Karp A Langenegger O and Roche R 1987 Community Water Supply The Handpump O ption The World Bank IRC International Water and Sanitation Centre 1988 Handpumps Issues and concepts in rural water supply programmes Technical Paper Series no 25 Still D A and van Niekerk T 2002 Handpumps in KwaZulu Natal Still the most important water supply methodology WISA Water Institute of Southern Africa Biennial Conference Durban 40 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation WE Solar Powered Pumps W hat is a solar powered pump and how does it work A solar pump
19. off the rock face by a low wall which leads to a low point The water is then led through a filter and then conveyed to large storage tanks or a storage dam Rainwater harvesting requirements The material selected should be easy to clean and should not pollute the water being collected Examples of appropriate material include corrugated iron with no lead based paint tiles with no lead flashing plastic concrete and asphalt 27 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation With rainwater harvesting from the roof a good guttering and down pipe system must be constructed from PVC fibre cement aluminium or impermeable grade shade cloth With ground or rock face rainwater harvesting a collection system is required along a low edge often a low wall which must slope to a low point From here the water is piped to a storage tank With ground and rock face rainwater harvesting a simple filter helps to remove dust droppings etc A storage tank should be designed and constructed taking into account the material available and the size of the tank required The size of the tank depends on rainfall patterns and the water demand In South Africa storage of up to nine months might be necessary This water is often used in conjunction with lower quality ground and surface water sources the rainwater being used for potable uses whilst the other sources are used for washing bathing etc Water qualit
20. septic tanks biological digesters and pit latrines in South Africa WRC report no 544 1 00 Palmer Development Group 1994 Water and sanitation handbook for community leaders urban and peri urban WRC Report No TT 68 95 South African Bureau of Standards 1990 SABS 0400 1990 Code of Practice for the Application of the National Building Regulations TECHNOLOGIES FOR THE CONTROL OF WATER SUPPLY AND PAYMENT OPTIONS Brikk F and Rojas J 2001 Key factors for sustainable cost recovery in the context of community managed water supply Occasional Paper Series 32 E IRC International Water and Sanitation Centre Delft Netherlands Evans P 1992 Paying the piper An overview of community financing of water and sanitation Occasional Paper 18 IRC International Water and Sanitation Centre 98 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation WATER TREATMENT Jacobs E P Pillay V L Pryor M and Swart P 2000 Water supply to rural and peri urban communities using membrane technologies WRC Report no 764 1 00 Letimela O N 1993 Denitrification of groundwater for potable purposes WRC Report no 403 1 93 Liao A 2001 Tending to Water Needs Improving wells the right way In Water Well Journal July 2001 Pillay V L 1998 Development of a crossflow microfilter for rural water supply WRC Report no 386 1 98 Sanderson R D Jacobs E P Hurndall M J Van Reenen A J
21. surface and it is advisable that the rope and washers are enclosed at all times This pump is inexpensive and relatively easy to construct however it can only be used for relatively low lifts of less than 30 metres 87 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Afridev This is the most common VLOM pump in South Africa It functions effectively for lifts of less than 45 metres It is less suitable for deep wells The long lever makes it easy to operate even for children The PVC column is resistant to corrosive waters but the solvent welded joints make it difficult to re install the column properly after repair Alternative jointing systems are being considered Vergnet Only a few of these pumps have been installed in South Africa but they are widely used in Francophone Africa This is a foot operated pump that is easy to install and repair It is not manufactured in South Africa the pump and all its parts have to be imported from France making it costly 88 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water Treatment Household Level Treatment Boiling of Water The boiling of water can destroy most micro organisms in the water to make it safe for drinking The water should be boiled for at least 10 minutes Disinfection Household bleach can disinfect water if the water does not contain too much soil or organic matter and with the proper dosa
22. tanks is also necessary Advantages of cloud or mist harvesting Advantages of cloud or mist harvesting include The structures can be constructed with locally available materials The collectors can often be erected in close proximity to the user The amount of water collected can be varied according to the number and size of the collectors e The source is generally sustainable over many years Water may be collected from fog during dry periods and even through drought periods and If users participate in the installation of the system additional training for maintenance will not be necessary Limitations of cloud or mist harvesting Limitations of cloud or mist harvesting include Fog formation is often irregular in nature and this system is highly sensitive to climatic changes lf the users are not located near the harvesting point the installation of mechanisms to pipe the water in areas of high topographical relief may be costly and Only small quantities of water are produced 31 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Practical experience Pilot projects have been conducted in South Africa and Namibia In South Africa these have been conducted along the West Coast in high altitude areas in the Limpopo Province and in the Eastern Cape Key references Olivier J 2003 Fog Harvesting An alternative source of water on the west coast of South Africa S
23. the surface by an underlying impermeable layer or by artesian pressure Spring protection refers to the modification of a spring source to capture the available water before it becomes exposed to surface contaminants This is done by Excavating the spring until the water emerges from stable ground Construction of a spring capture chamber Construction of a sedimentation chamber Construction of a storage reservoir to accommodate fluctuations in demand Construction of diversion drains and ground stabilising structures where required and e Fencing and establishing grass within the spring area If the spring is above the settlement water can be piped directly from the reservoir into a reticulation If the spring is below it can be pumped to another reservoir and then from there into a reticulation Spring protection requirements Overflow should be directed back to the stream Further the spring should be protected against surface water contamination and erosion At all times water from the spring should be allowed to flow freely away from the eye or source of the spring without obstruction 18 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation The water should never dam up as this will cause back pressure This can lead to the groundwater finding an easier alternative route and the spring could stop flowing The water must flow freely under maximum flow conditions during construc
24. unprotected With unprotected wells water is collected using a bucket or steps can be cut into the side of the well to fetch the water directly These wells carry a high risk of contamination Also children and animals can fall in An upgraded hand dug well is preferable It has the following components e A headwall or protective collar that prevents surface water from entering the well and children and animals from falling in A well cover which is cemented onto the collar and leaves a small central hole for lifting water using a bucket e A windlass which is used to raise and lower a bucket with a hook on which the bucket should be hung when not in use and e A drainage apron and soak away which ensures that spilt water will drain away and not dam up around the well causing contamination and health hazards 12 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation The final upgrade for a hand dug well is the installation of a hand or motor driven pump at the surface This further reduces the chances of contamination and makes the extraction of water easier Hand dug well requirements The depth to which the well must be dug the optimum diameter of the well and the level of service must be determined This is based upon specific hydrological conditions Water quality The water quality of the well is dependant on the inherent properties of the groundwater Further it may be affected by contaminati
25. A A 1987 A technical and social analysis of alternative water pumping technologies for underdeveloped rural areas prepared for the Foundation for Research Development by the Energy Research Institute SANITATION TECHNOLOGIES Brikk F Bredero M de Veer T and Smet J 1997 Linking Technology Choice with Operation and Maintenance for Low cost Water Supply and Sanitation Operation and Maintenance Working Group of the Water Supply and Sanitation Collaborative Council IRC International Water and Sanitation Centre World Health Organisation Cotton A Franceys R Pickford J and Saywell D 1995 On plot Sanitation in Low income Urban Communities A review of literature WEDC CSIR 1991 Part Guidelines on the cost effectiveness of rural water supply and sanitation projects Part Il Guidelines on the technology for and management of rural water supply and sanitation projects CSIR Appropriate Technology Group Water Care Programme Division of Water Technology W RC Report No 231 1 93 DWAF Sanitation Support 2001 Study Report on Management of Faecal Waste from On site Sanitation Systems in South Africa Kalbermatten M Julius D S and Gunnerson C G 1980 Appropriate Technology for Water Suppy and Sanitation A Sanitation Field Manual World Bank Morgan Peter 1990 Rural water supplies and sanitation A text from Zimbabwe s Blair Research Laboratory Macmillan London Norris G A 2000 Sludge build up in
26. Affairs and Forestry Lenehan A M and Abelitis L 2003 An assessment of the trickle feed system as a tool for implementing the free basic water policy WRC Report no TT210 03 82 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation 5 BACKGROUND INFORMATION DESCRIPTIONS OF PUMPS WATER TREATMENT Household Level Treatment Municipal Level Treatment 83 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Descriptions of Pumps Any pumping system requires two basic components the pump driver and the pump The pump is the device that lifts the water and the driver is the source of energy The very simplest pumping system is a person the pump driver lowering and raising a bucket on a rope the pump in and out of a well The following pump drivers are found in practice Petrol engines Diesel engines Electric motors Wind solar Animal People Usually used for small portable pumps for example pumps for food gardens fire fighting and water tankers Used for larger pumping installations where no grid electricity is available Diesel engines are more economical to run and last longer than petrol engines Favoured for practically all static pumping installations where grid power is available Electric motors are easily automated which is a key advantage Solar or wind power can be economically used to drive small pumps for low vo
27. Introductory Guide to Appropriate Solutions for Water and Sanitation NORAD DIREKTORATET FOR UTVIKLINGSSAMARBEID NORWEGIAN AGENCY FOR DEVELOPMENT COOPERATION TOOLKIT for WATER SERVICES Number 7 2 This guideline is for use by municipalities and their service providers as an introduction to the range of appropriate solutions available for water supply and sanitation and where and how these are suited to different situations Tet ea Introductory Guide to Appropriate Solutions for Water and Sanitation DWAF March 2004 Published by Department of Water Affairs and Forestry Directorate Information Programmes Private Bag X313 PRETORIA 0001 Republic of South Africa Tel 012 336 7500 This publication may be reproduced only for non commercial purposes and only after appropriate authorisation by the Department of Water Affairs and Forestry has been provided No part of this publication may be reproduced in any manner without full acknowledgement of the source Implemented by Council for Geoscience Written by Richard Holden and Tania Swanepoel Editing Kate Skinner Anthea Josias Kerry Harris Artwork Vusi M alindi Layout and design Gill McDowell Inputs Boniface Aleobua Phillip Ravenscroft Gary Small David Still Leslie Strachan Riana Terrblanche Rian Titus Peter Zawada Produced under The NORAD Assisted Programme for the Sustainable Development of Groundwater Sources under th
28. Sludge gradually builds up in the tank and a tanker is required for its removal Access for de sludging must be provided Also a household water connection and an operational central sewage treatment works are required Groundwater and the system Leakage in the system if undetected may infiltrate the sub surface resulting in groundwater contamination If nitrates are not removed they may affect the groundwater 59 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water requirements A reliable 24 hour piped water supply is required Greywater The system can accept greywater but the amount needs to be governed by the size and Capacity of the soakaway Level of comfort The toilet can be located inside the house A water trap prevents smells from the sewage entering the toilet and uncomfortable draughts whilst using the toilet Insitutional support Institutional support is required for Emptying of tanks and transportation to the sludge treatment works The establishment as well as operation and maintenance of the treatment works The billing associated with the use of the treatment works and Effective credit control Capital requirements Capital costs include An on site piped water supply A structure to house the toilet this cost can be reduced if the toilet is placed inside an existing house The cistern The pedestal On site reticulation The septic tank
29. The consumption of freshwater is reduced and The amount of water passing through the wet sanitation system if there is one is reduced Limitations of greywater recycling The limitations include that greywater cannot be stored for more than 24 hours unless it has been treated otherwise it can turn anoxic or anaerobic Practical experience Approximately 1500 household units have been installed in South Africa 34 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Key references Holden R 2001 The use of dry sanitation in the urban environment The Mvula Trust Braamfontein U seful websites www Water Rhapsody co za www greywater com www oasisdesign net greywater 35 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation 2 SOURCES OF POWER FOR PUMP SYSTEMS INTRODUCTION SOURCES OF POWER FOR PUMPS Hand Pumps Solar Powered Pumps Wind Powered Pumps Diesel Powered Pump Electric Pumps 36 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Introduction This section covers the range of energy sources available to power pumping systems rather than the different types of pumps Experience has shown that electricity from the grid is the most efficient way of powering motors The energy is generated at a central point and brought to the site without the need for transport However its main dra
30. a WRC No 521 1 98 76 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Individual Households A number of technologies can be utilised to serve communities at household level They include the following e An electrical pre paid dispensing meter A trickle feed system e The Ethekwini Durban tank system and e Arrear billed mechanical meters The advantages and disadvantages of the different technologies are unpacked below Electrical Pre Paid Dispensing Meter This system uses coupons The householder takes these to a central point where they purchase credits which are loaded onto the coupon Water consumption is then controlled in terms of the number of credits purchased The coupon is placed in the slot and water runs until the credits on the coupon are exhausted This system is relatively expensive to install Further outside assistance is required for operation and maintenance The advantage of this system is that the credits can be sold through any retail point and the consumer is immediately aware of their expenditure The disadvantage is that purchases by the consumer might not be on a regular basis making it difficult to introduce rising block tariffs Another disadvantage is that if the meters fail they fail in the closed position cutting off the householder s water supply It is therefore critical that a repair team is on constant standby to replace meters Elec
31. a set amount of water from a holding tank in the meter A tap with an electrical pre payment dispensing meter A coupon is inserted The water flows until the credits are exhausted or the tap is closed This technology dispenses the exact amount of water required The advantages and disadvantages of the different technologies are discussed below Normal Tap There is no control over how much a consumer can use The potential for water wastage is high Community members need to bear the responsibility of ensuring that taps are turned off correctly Some communities deal with the issue of water wastage by locking their standpipes and only opening them at certain times of the day However the consumption of water is generally low if water wastage is dealt with effectively Normal tap technology is cheap It is easy to install and easy to maintain Outside interven tion may be required for installation of standpipes but the community can manage On going operation and maintenance Push Button Tap There is some control over how much a consumer can use The potential for water wastage is lower with this option only a set amount of water is released If people do not have the correct size container water may be wasted but research has shown that this is less than if taps are left open The technology is cheap easy to install and easy to maintain Outside intervention may be required for installation of standpipes However the community ca
32. accruing high energy bills In effect the diesel system is a pre payment system Limitations of diesel powered pumps The limitations include e In rural areas there are not always trained mechanics to maintain and repair diesel engines e Diesel engines are hard to automate and an operator is required to switch the engine on and off and e The logistics of supplying diesel in rural areas can be difficult Practical experience The use of diesel powered pumps is widespread in the South Africa Key reference Baumann E 2000 Series of manuals on drinking water supply volume 7 Water lifting SKAT Switzerland 48 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation W Electric Pumps W hat is an electric pump and how does it work Electricity is used to power the motor The motor can be a separate unit attached to the pump through V belts gearboxes or shafts This type of motor is situated on the surface Alternatively the motor can be integrated with the pump as in a submersible pump The pump is then located within the water Electric pump requirements The motor chosen must be of the right size for the anticipated workload Further a storage tank is required for periods when the pump is not in operation and to balance fluctuations in demand 49 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Insitutional support Repairs
33. antages include High levels of comfort and convenience and The user does not have to handle waste Limitations of conservancy tanks Limitations include e There must be access for tankers to empty the tank e Overflow can easily occur during peak social events and e The user must ensure that the municipality collects the sewage on a regular basis Practical experience This toilet is used in a number of municipalities in South Africa where septic tanks with soak aways are not deemed appropriate Key references DWAF Sanitation Support 2001 Study Report on Management of Faecal Waste from On site Sanitation Systems in South Africa DWAF 2002 Sanitation for a Healthy Nation Sanitation Technology Options 58 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation W Flush Toilet with Septic Tank and Soakaway What is a flush toilet with a septic tank and a soakaway and how does it work Waste from the toilet and greywater are flushed into the septic tank The solids are retained in the tank whilst the effluent is led to a soakaway The time that it takes to fill the tank is dependent on the number of users The typical filling rate is 30 litres per user per year The sludge is taken to a sewage treatment works Septic tank requirements The soil must provide good drainage for the soakaway to work There should be sufficient space on the property to allow for this
34. areas such as hills or mountains and on coastlines with a cold current offshore The collectors are easy to construct and only require wind energy A number of systems may be required to provide an adequate supply for a particular settlement Cloud or mist harvesting requirements Cloud mist must occur frequently throughout the year It should have a high moisture content and be accompanied by a wind to ensure that the moisture is blown through the collecting screens Water quality The water is usually potable but may contain some dust and be salty in areas close to the coast 30 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Insitutional support Professional assistance is needed to determine the suitability of a site for cloud mist collection the determination of the projected yield as well as the construction of fog nets and their proper positioning Capital requirements Costs are associated with Shade cloth nylon mesh Wooden poles Steel cables Bolts nuts washers and clamps Rope Pipes and Storage tanks o 2 O peration and maintenance General quality checks to the fog collector system should include checking the cable tensions cable fasteners and horizontal net tensions Further maintenance repair and or replacement of the nets are required Dust should be washed out of the gutter at regular intervals Regular maintenance of pipes and storage
35. ate Sector Participation in Low Cost Water Well Drilling Cranfield U niversity First Edition July 2000 Calorama Rural Development Services 1997 Low Cost Water Supply Series Volume 3 1st Edition Eijkelkamp Agrisearch Equipment 1999 Drilling sets for shallow wells FAO 2003 Smallholder irrigation technology Prospects for sub Saharan Africa on Food and Agriculture Organisation of the UN website www fao org Finkel M and Segerros M 1995 Report No 33 Water harvesting proceedings of the SADC ELMS practical workshop Namibia 10 28 May 1993 Gould J 1999 Rainwater Harvesting Information Resources Booklet for Southern Africa Houston P and Still D 2001 An overview of rainwater harvesting in South Africa Mvula Trust and D WAF Louw C van Heerden J and Olivier J 1998 The South African fog water collection experiment M eteorological features associated with water collection along the eastern escarpment of South Africa Water SA Vol 24 No 4 269 280 Macdonell Andrew 2000 Ferro cement Rainwater Tank Construction M anual Pambili Water and Sanitation Project M bugua J and Nissen Petersen E 1995 Rain Water an under utilized resource Swedish International Development Authority SIDA Nairobi Morgan P 1990 Rural water supplies and sanitation A text from Zimbabwe s Blair Research Laboratory London Mouton P and Wilken P 2001 An Assessment of Alternative Technologies for Cost effectiv
36. ation Resources Booklet for Southern Africa Houston P 2001 A synthesis of rainwater harvesting models The development of an appropriate Southern African model Partners in Development prepared on behalf of The M vula Trust Houston P and Still D 2001 An overview of rainwater harvesting in South Africa Prepared by Partners in Development on behalf of The M vula Trust and the Department of Water Affairs and Forestry Houston P and Still D Rain Water Harvesting A neglected rural water supply option Partners in Development 29 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation WE Cloud Mist Harvesting i p m ea a Se ae ee ba gee A e a A Sn oe ig a 2 Eann am i e b ie W hat is cloud or mist harvesting and how does it work In cloud or mist harvesting water droplets are intercepted and collected in a system comprising of vertical rectangular panels of nylon mesh or shade cloth supported on either side by wooden posts and held up with steel cables This structure is then placed perpendicular to the direction of the prevailing wind The water droplets in the cloud or mist precipitate onto the mesh fall into gutters at the bottom of the panel and are then led under gravity to a storage tank Storage must be provided for several days to cater for times when there is minimal or no cloud or mist This system is suitable for cloud or mist prone
37. can easily accommodate peak usage during social events since it is part of a larger system Limitations of waterborne sewerage Limitations include e A developed infrastructure and institutional capacity is required for construction operation and maintenance and for billing and credit control of the system e Underground leaks are extremely difficult to detect e Blockages can cause large amounts of environmental pollution unless the responsible institution has a rapid response time e When blockages occur on private property and the owner fails to act by laws are often not framed to allow the municipality to act quickly and recover costs Problems may arise if the sewage treatment works are not able to treat volumes of sewage from the whole system to the required standard If soft toilet paper is not used blockages may occur and e The system can be used as a means of disposing unwanted material such as rubbish and foetuses causing serious blockages Practical experience This sanitation option is used extensively in urban areas across the world However extreme environmental problems have arisen when treatment has not been provided or the system has not been maintained Key references DWAF Sanitation Support 2001 Study Report on Management of Faecal Waste from On site Sanitation Systems in South Africa DWAF 2002 Sanitation for a Healthy Nation Sanitation Technology Options 55 Introd
38. cipality and given to the vendor to get the water The vendor then takes the coupons to the municipality where they are checked against the meter readings The community members pay the vendor and the vendor pays the municipality on the basis of water readings The vendors are paid either on a commission basis or a set wage by the municipality or The vendor charges whatever mark up they want on the water bought from the municipality One of the key requirements of this system is that the number of people buying from the kiosk must be high enough for the vendor to make a living without making the water too expensive This is usually only possible in more densely populated urban areas 75 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Pre payment system Pre payment systems include both electrical and mechanical meters Payments are made upfront No costly bills are generated in arrears The limitations come from the costs of implementing the technology and operating and maintaining the system The free basic water policy is facilitated through allocating a number of free credits or tokens to householders Key references DWAF 1997 Implementing Prepayment Water Metering Systems Department of Water Affairs and Forestry Hazelton D and Kondlo S 1998 Cost recovery for water schemes to developing urban communities A comparison of different approaches in the U mgeni Water planning are
39. consists of an array of photovoltaic cells that convert solar radiation into electricity that drives an electric pump Although solar pumps can pump up 200 metre heads they are most cost effective up to a pumping head of 50 metres Solar pump adaptations Solar panels can be used in conjunction with batteries to provide capacity to store energy and thus to ensure continuous pump use Also solar panels can be used in conjunction with a diesel pump but this increases the operation and maintenance costs of the system Solar pump requirements There are a number of requirements e The pump requires sunlight e A storage tank is needed for cloudy days and nights when there is no sunlight to pump water A tank is also needed during periods when the pump Is being serviced or repaired and to balance any fluctuations in demand e An electric motor must be selected with care to ensure that the system can operate over a range of voltage and current levels depending on the intensity of the sunlight If the electric pump uses alternating current a DC AC converter is needed to convert direct current to AC current DC current is produced by the photovoltaic cells Insitutional support When problems arise with solar systems even simple electrical faults it is often necessary to call in a specialist from one of the major centres Capital requirements Capital costs per unit of power watt produced are very high Costs are associated with
40. ditions and the availability of equipment power sources and skills The water is brought to the surface by a pump or a small diameter bucket or bailer Borehole requirements The depth of the borehole should accommodate seasonal or annual fluctuations in water levels so as to avoid the borehole going dry when the water table is low A hydrogeological survey to determine the appropriate siting of the borehole is recommended The optimum diameter of the borehole must be determined taking into account the anticipated yield the demand and the extraction method used 9 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water quality Water quality depends on the inherent properties of the groundwater when extracted threats of contamination during the extraction process and threats of contamination from the surrounding environment However it is important to remember that groundwater is still generally better quality than untreated surface water Further there is less of a chance of contamination from boreholes than from hand dug wells A sanitary seal should prevent contaminants from entering down the side of the borehole casing Insitutional support Consultation with qualified and experienced professionals is required to determine the position of the site and for drilling testing and pumping yield recommendations Capital requirements Costs are associated with Drilling auguring equipment Casin
41. e The choice of hand pump depends on lift characteristics pump capacity water demand and ease of maintenance and The pump must be suited to on site conditions i e be able to lift water from depth if this is required 38 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Insitutional support Village level operation and maintenance VLOM pumps do not require outside support if Community members are trained and are given the appropriate tools However other pump designs may require external assistance One of the important issues here is that since the energy source is free there are no monthly charges However money must be still raised for routine maintenance and possible breakages Capital requirements Capital costs are associated with the purchase of the pump installation construction of an apron and drainage system and fencing O peration and maintenance Hand pumps can withstand irregular maintenance far better than electrical or diesel pumps However common aspects that require maintenance include failure of the anti reverse system failure of the bearings in the head and excessive wear of gears in geared head pump units Generally less maintenance is required for pumps designed with the VLOM philosophy They are designed for ease of maintenance low capital and recurrent costs and robustness They are manufactured to a standard publicly available design and therefore the consumer is
42. e Groundwater Abstraction WRC Report no K5 732 95 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Parr J Smith M and Shaw R 2000 Technical Brief no 64 Wastewater treatment options In Waterlines Vol 18 No 4 April 2000 Pearson L A Bhagwan J Kariuki W and Banda W 2002 Guidelines on Appropriate Technologies for Water Supply and Sanitation in Developing Communities WRC report no 520 1 01 Sami K and Murray EC 1998 Guidelines for the evaluation of water resources for rural development with emphasis on groundwater WRC Report No 677 1 9 SKAT 1985 Manual for Rural Water Supply with many detailed constructional scale draw ings SKAT ATOL St Gall Smakhtin V Ashton P Batchelor A Meyer R Murray E Barta B Naidoo D Olivier J Terblanche D and Bauer N 2001 Unconventional water supply options in South Africa Possible solutions or intractable problems Water International Vol 26 No 3 pp314 335 Smet J and van Wijk C 2002 Small Community Water Supplies Technology people and partnership IRC technical paper series 20 Smith M and Shaw R 1993 Technical Brief no 37 Re use of wastewater In Waterlines Vol 12 No 1 July 1993 UNEP 1997 Sourcebook of alternative technologies for freshwater augmentation in Latin America and the Caribbean UNEP 2000 Sourcebook of alternative technologies for freshwater augmentation in Africa
43. e Community Water and Sanitation Programme in South Africa Foreword Toolkit for Water Services Groundwater has historically been given limited attention and has not been perceived as an important water resource in South Africa This is reflected in general statistics showing that only 13 of the nation s total water supply originate from groundwater However because of the highly distributed nature of the water demand in rural and informal peri urban settlements regional schemes are in most instances not economically feasible And because of generally increasing water scarcity and decreasing available river and spring flows during low flow and drought periods as well as wide spread problems of surface water pollution in rural areas groundwater will be the most feasible option for a large part of the new water demand Already it is estimated that over sixty percent of community water supply is from groundwater making it a strategically important resource The NORAD Assisted Programme for the Sustainable Development of Groundwater Sources under the Community Water and Sanitation Programme in South Africa was managed by the Department of Water Affairs and Forestry D WAF between 2000 and 2004 The Programme undertook a series of inter related projects aimed at enhancing capacity of water services authorities and DWAF to promote and implement sustainable rural water supply schemes based on groundwater resources and appropriate tec
44. e a slotted well screen Finally the tube well should include a well drained concrete slab Water quality Water quality depends on the inherent properties of the groundwater Further it depends on possible contamination during the extraction process from the surrounding environment Generally however groundwater is purer than surface water Tube wells have a lower risk of contamination than hand dug wells A sanitary seal should prevent contaminants from entering the groundwater from the surface down the side of the tube well casing 15 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Insitutional support Professional expertise is required for siting testing recommending pumping yields if a motorised pump is installed and monitoring construction quality Local artisans can be trained to carry out construction and maintenance Capital requirements Costs are associated with Drilling auguring equipment Casings Screens and The sanitary seal o O peration and maintenance Tube wells that have become clogged may need remediation work Advantages of tube wells Advantages of tube wells include They are cheaper per metre than hand dug wells as less material needs to be removed They are cheaper than drilling rigs in soft formations They can be constructed within short timeframes and They can be sunk deeper than hand dug wells in unconsolidated sand and may theref
45. e area at a specific time Borehole Defined by the National Water Act 1998 as a well excavation or any artificially constructed or improved underground cavity which can be used for the purpose of a Intercepting collecting or storing water in or removing water from an aquifer b Observing and collecting data and information on water in an aquifer or c Recharging an aquifer Catchment Management Agency CMA CM As are responsible for regional water resource management National Water Act 1998 Determinands Variables such as ions pH and temperature to be included in a water quality assessment Dip meter The instrument used to measure the depth to the water level in a borehole Groundwater Water held within a saturated soil rock medium fractures or other cavities within the ground SANS 2002 Groundwater level The depth to the water level in a borehole or well from the ground Groundwater management Groundwater management for Community Water Supply involves taking responsibility for protecting groundwater from contamination and ensuring its sustainable use The main responsibilities are a Data collection capture and analysis and recommendations for operational or behavioural changes based on the data analyses Operational changes may be for example to reduce the abstraction rate Behavioural changes may include for example the restriction of groundwater polluting activities or increasing the monitoring freque
46. e sediment in the water Access to the pipes is required for cleaning and inspection 21 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water quality The water is usually of good quality as the sand generally filters out contaminants Insitutional support The level of institutional support required depends on the scale of the project Professional expertise is necessary to determine the yield of the aquifer and to design the system Local labour can be used for construction Capital requirements Capital requirements include the digging of trenches the cost of pipes and screens and the abstraction chamber O peration and maintenance Flow rates should be monitored to detect any unusual increase or reduction in flow Pipes should be cleaned after two years of operation and or depending on the amount of sediment found An initial assessment can help in determining how often the pipes should be cleaned Advantages of sand dam abstraction Advantages of sand dam abstraction include The water is generally clean since it is underground and e Evaporation losses are reduced Limitations of sand dam abstraction Limitations of sand dam abstraction include Problems with clogging of screens and scouring of sand from behind the screen may be encountered and Ifthe raw water has a high iron or manganese content the abstraction screens will clog greatly reducing the yield Practical experience They
47. ea so the toilet is therefore suitable for areas where space is limited 63 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Limitations of twin pit composting toilets Limitations include The user must be willing to handle the compost The sides of the pit may require lining if the soil is unstable Sufficient soil and biodegradable organic wastes such as garden and vegetable waste must be on hand and e Land needs to be available close by where the compost can be used If this is not available a transport system needs to be accessible for waste removal purposes Practical experience This technology has been used with success in Zimbabwe Mozambique Malawi and Kenya Reference Visit the following website http aquamor tripod com 64 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation W Urine Diversion Dehydrating Toilet W hat is a urine diversion dehydrating toilet and how does it work A urine diversion pedestal is used to keep the urine and the faecal matter separate The faecal matter drops into a vault below the pedestal The vault needs to prevent groundwater or rainwater entering After each visit to the toilet dry soil ash or a mixture of both is added so as to control moisture content and to prevent biological breakdown Urine is diverted at the pedestal This may be collected and used as a fertiliser or lead to a s
48. en the pump is not in operation to balance fluctuations in demand e Fuel must be delivered on a regular basis e An operator is required to turn the pump off and on and e Trained personal must conduct maintenance checks and services Insitutional support Arrangements must be made to purchase fuel oil and other consumables Regular maintenance must be organised and back up must be ensured during breakdowns Insitutional support Capital costs are associated with the purchase and installation of the engine pumphouse and reservoir 47 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation O peration and maintenance Engine oil and filters must be replaced regularly usually after 250 hours of operation Further spare parts fuel supplies and regular servicing are essential Engines should not be run at a speed exceeding 70 to 80 of capacity as this may lead to premature wear and inefficiency But further engines should not be run much below this level as this leads to a build up of excessive carbon deposits in the cylinder i e coking Advantages of diesel powered pumps Advantages include Diesel engines have a high power to weight ratio and can be used to drive almost any type of pump e There are no overhead costs during periods of non use unlike in the case of an electricity grid which has high basic charges and e Diesel is purchased upfront which means that consumers are prevented from
49. ery high charges can be incurred before the householder realises what is happening This method is used extensively in most urban areas of South Africa where there are house connections 80 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Payment systems for individual households A number of payment systems are available to recover the tariff from the consumer No payments are collected Ethekwini Metro has implemented the free basic water policy in conjunction with its tank system The tank system provides 200 litres of water per household per day This works out to approximately 6 000 litres per household per month Ethekwini Metro supplies this water to households free of charge No meter reading accounts or credit control sections are required by the water services authority or water services provider Meters are installed only for loss control purposes Although the costs of implementing the system are high the operation and maintenance costs are low Since no payment is required the system is easy to manage A flat rate is collected The Ethekwini Durban Tank system and other trickle feed systems allow for the charging of flat rates This significantly simplifies the billing system No meter readings are required Payment is collected up front If a pre payment system is implemented credits must be purchased up front The benefit of this system is that large accounts cannot be generated
50. esel pumps Rural communities however often face problems due to issues of theft and high costs of maintenance 42 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Key references PV Pump Technical Information Sheet Davis M Burchers M Dickinson B and Geerdts P 1994 Institutions and Financing For Effective Dissemination of PV Systems for Rural Development Energy for Development Research Centre Cape Town Gosnell R 1991 Demonstration and Evaluation of a Photovoltaic Powered Water Pump Energy for Development Research Centre Cape Town Kenna J and Gillet B 1985 Solar Water Pumping A Handbook Intermediate Technology Development Group London Village Water Supply Section 1994 Solar pumping systems manual Ministry of Home Affairs Government of the Kingdom of Lesotho Maseru Wiseman K and Eberhard A 1987 A technical economic and social analysis of alternative water pumping for underdeveloped rural areas Energy Research Institute University of Cape Town 43 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation E Wind Powered Pumps oa W hat is a wind powered pump and how does it work Wind powered pumps use the energy generated by wind to lift groundwater to the surface A rotor is mounted on top of a tower The action of the wind turns the rotor which through a gearbox drives a reciprocating shaft This in turn drives the pump in t
51. estal Digging a pit and The vacuum tanker and treatment works if mechanical emptying is envisaged The total cost depends on the materials used Costs can be reduced if the users do all or some of the work themselves O peration and maintenance Breeding of mosquitoes in wet pits can be prevented by adding a cupful of a suitable inhibitor such as lubricating oil or diesel each week When the pitis full the toilet must either be moved to a new pit or provision must be made to empty the pit 69 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Advantages of ventilated improved pit toilets Advantages include e The toilet can be built by the householder and All types of anal cleansing materials may be used although some will cause the pit to fill faster than others Limitations of ventilated improved pit toilets Limitations include If emptying the pit is not an option land is required for the construction of a new pit this is not an option in dense settlements Ifthe pitis to be emptied there must be access for vehicles e The pit is often used as a rubbish dump thus shortening its lifespan and If the toilet is to be moved it cannot be constructed with bricks or cement blocks Practical experience This sanitation option is widely used internationally as well as in rural and peri urban areas across South Africa Key references Bester J W and Au
52. for protecting springs 3 3 Guidelines for protecting boreholes and wells 3 4 Guidelines on protecting groundwater from contamination 3 4 1 Animal kraals watering points and dipping tanks 3 4 2 Burial sites 3 4 3 Informal vehicle servicing spray painting and parts washing facilities 3 4 4 Pit latrines 3 4 5 Runoff water 3 4 6 Subsistence agriculture 3 4 7 Informal waste disposal 4 Maps 4 1 Thematic Groundwater M aps 5 Software 5 1 Sustainability Indexing Tool SuslT 5 1 1 SuslT User Guide 5 1 2 SuslT Field Data Capturer s U ser M anual 5 1 3 SuslT Questionnaire 5 1 4 SuslT Information Brochure 5 2 AquiMon Management System 5 2 1 AquiMon Information Brochure 5 3 Geohydrological Data Access System GDAS 5 3 1 GDAS Information Brochure 6 Monitoring 6 1 Groundwater Monitoring for Pump Operators 7 Sustainability 7 1 Sustainability Best Practices Guidelines for Rural Water Services Introductory Guide to Appropriate Solutions for Water and Sanitation 7 3 Decision Making Framework for M unicipalities 8 Reference Sites 8 1 Genadendal Information Brochure 8 2 Kammiesberg Information Brochure 8 3 Maputaland Information Brochure 2 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Table of Contents Foreword Toolkit for Water Services Acronyms Introduction to the Guide 1 Water Supply Technologies Introduction Water Supply Technologies Groundwater Bo
53. g of the bottom of infiltration basins e Monitoring and managing the recharge water quality e Monitoring the efficiency of injection wells to detect clogging and Restoring the efficiency of injection wells with backflushing or other methods Advantages of artificial recharge Advantages of artificial recharge include Itallows for the maximising of natural underground storage capacity until water is needed i e in times of drought and It allows for the optimal use of water that may otherwise have been lost to evaporation Limitations of artificial recharge Limitations of artificial recharge include Artificial recharge schemes need to be designed according to the local geological water quality and institutional conditions in place otherwise their efficiency will decrease Recharge water may introduce contaminants into the groundwater High evaporation rates and the presence of clay lenses can make infiltration basins less effective and Clogging of the injection well system due to mechanical physical chemical and biological processes can be a severe limitation to the success of the system 25 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Practical experience Artificial recharge schemes exist throughout the world Earth dams are found on farms across South Africa and in some cases these act as a means of artificial recharge O perational artificial recharge si
54. ge Five millilitres one teaspoon of bleach should be added per 25 litres of water The water then needs to be left to stand away from sunlight for at least two hours Disinfection is effective as long as the water is not heavily polluted HTH granules and pills can also be used to disinfect water in larger quantities Filtration Filters available for household use range from expensive membrane filters to cheaper filters that can be constructed by the householder The filtration method may not remove all micro organisms so disinfection might be required after filtration to ensure safe drinking water Solar Disinfection SO DIS Solar disinfection is the disinfection of water using the sun s rays SODIS can be used to treat small quantities of water at household level Water should be placed in plastic bottles and exposed to sunlight On bright days or when there is up to 50 cloud cover the water should be exposed for 5 hours On cloudy days the water should be exposed for two consecutive days The disinfection process can be speeded up by adding oxygen to the water This can be done by shaking the bottle vigorously both before exposure and every hour during exposure The temperature of the water is raised through exposure to sunlight which increases the effectiveness of this method Settlement Suspended solids can be removed from the water by allowing the water to stand until the solid particles settle at the bottom of the container C
55. gs Screens and A sanitary seal Operation and maintenance If the borehole yield decreases over time boreholes may need to be remediated Clogging may be improved by cleaning out the borehole using a weak acid solution under high pressure Abstraction from the borehole and water levels must be regularly measured to avoid over abstraction and the borehole running dry Advantages of boreholes Advantages of boreholes include Boreholes are the only means of extracting water in hard rock environments They are more efficient per metre than hand dug wells as less material needs to be removed They can be constructed within short timeframes and e The water source is generally reliable as they can extend deeply to reach reliable aquifers 10 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Limitations of boreholes Limitations of boreholes include e The borehole offers limited storage capacity for low yielding aquifers e Problems with clogging of screens and scouring of sand from behind the screen may be encountered Ifthe raw water has a high iron or manganese content the abstraction screens will clog greatly reducing the yield Uncased boreholes are liable to collapse in highly weathered formation Expert advice must be sought to establish when casing is necessary or not Down hole equipment must be used for down hole maintenance and Borehole drilling costs are highe
56. he borehole Wind pump adaptations The air lift groundwater pump was developed to provide a low cost pump for use in informal and rural settlements This pump system can be operated with tyre pumps It has a wind pack compressor capable of storing wind energy as compressed air This provides supplementary power to the pump All the working parts of this pump are located above ground making maintenance easy Wind pump requirements The pump requires sufficient wind speeds for significant lengths of time The wind pump must therefore be placed where there is a clear sweep of wind Also the borehole should provide enough water so that continuous pumping does not result in excessive drawdown Storage for several days must be provided to cater for calm periods when there is insufficient wind speeds to pump water Further someone must be delegated to apply the manual brake to avoid damage during storms 44 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Insitutional support The installation requires trained personnel Capital requirements Capital costs vary Costs depend on the depth of the borehole the size of the rotor and the height of the tower Capital costs are associated with The rotor The tower Transmission The storm control device and The reservoir O peration and maintenance Operation and maintenance should include the following e Lubrication of the gearbox and
57. he following Construction of the system Establishment as well as operation and maintenance of the treatment works e Municipal operation and maintenance of reticulation and bulk sewers including replacement of missing manhole covers detection and repair of leaks and removal of blockages The billing associated with the use of the reticulation and the treatment works and Effective credit control Capital requirements Capital costs include An on site piped water supply A structure This cost can be reduced if the toilet is placed inside an existing house A cistern A pedestal On site reticulation Municipal reticulation Bulk sewers and Treatment works OO gt O peration and maintenance The seal in the cistern will require replacement from time to time Rodding of on site pipes and the municipal reticulation is required to clear blockages If tree roots penetrate the sewer this will become a regular task unless the sewer is replaced Pump stations and treatment works must be constantly maintained Equipment must be replaced to ensure breakdowns do not occur polluting the environment 54 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Advantages of waterborne sewerage Advantages include High levels of user comfort and convenience The user does not have to handle waste since it is flushed away for the municipality to deal with and e The system
58. he spring should be controlled so as to prevent roots from damaging the spring box Further when required repairs should be done to the surface water drainage system Finally the sedimentation chamber must be regularly scoured and cleaned 19 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Advantages of spring protection Advantages of spring protection include e Spring protection prevents contamination of the water making further treatment unnecessary Spring protection can increase the yield obtained The simplicity of the technology used for spring protection allows for labour intensive construction to be carried out by local artisans The system taps base flow water and thus has no major impact on the local water table and Spring protection is generally inexpensive Limitations of springs Limitations of springs include e The supply may be low with seasonal reductions and e If construction is not carried out in an appropriate way the spring can find an alternative route underground thus bypassing the spring chamber Practical experience Many towns and settlements in South Africa were established because of their close proximity to springs A number of villages in Lesotho and the Eastern Cape are supplied with water using this technology Key references Meuli C and Wehrle K 2001 Spring catchment Volume 4 of series of manuals on drinking water supply SKAT S
59. hnologies Page 2 has a full list of the Programme outputs The formats for these range from documents to software programmes and an internet portal to reference sites where communities have implemented appropriate technologies For more information on the package of Programme outputs contact your nearest DWAF Regional Office or Head Office in Pretoria It is our sincere hope that this Programme will contribute to the body of work that exists to enable more appropriate use and management of groundwater in South Africa Introductory Guide to Appropriate Solutions for Water and Sanitation is Number 7 2 in the Toolkit for Water Services This guideline is for use by municipalities and their service providers as an introduction to the range of appropriate solutions available for water supply and sanitation and where and how these are suited to different situations 1 Introductory Gulde to Appropriate Solutions for Water and Sanitation fist bu can FIN Psa reer z Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Toolkit for Water Services 1 Overview documentation 1 1 A Framework for Groundwater Management of Community Water Supply 1 2 Implementing a Rural Groundwater Management System a step by step guide 2 Descriptors 2 1 Standard Descriptors for Geosites 3 Groundwater Protection 3 1 Involving community members in a hydrocensus 3 2 Guidelines
60. icals from soaps and detergents as well as organic materials It is not suitable for drinking However this water can be used safely for garden irrigation Plants take up the nutrients The amounts of pathogens in greywater are insignificant and are digested by organisms in the soil It should be noted that in the normal kitchen environment there are significant quantities of pathogens such as salmonella in chicken which are rendered harmless by cooking and washing 33 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Insitutional support The installation of a sophisticated greywater recycling system in an urban area may require professional guidance but simple systems can be built and maintained by the household Capital requirements Costs are associated with e Filters The storage chamber and A submersible pump piping and sprinkler If a less sophisticated system is used then a simple means of distributing the water manually is required O peration and maintenance Regular maintenance of the filter is required The sprinkler must be moved every couple of days or the water must be manually distributed Checks are important to ensure there are no blockages in the pipes as this could lead to the pump not switching off and thus burning out Advantages of greywater recycling Advantages of greywater recycling include Water that would otherwise be wasted can be used for irrigation
61. iciently with heads up to 100 metres The pump requires a maintenance team for installation services and repairs Bucket Pumps The Zimbabwe Bucket Pump developed by the Blair Institute in Zimbabwe is a simple inexpensive technology suited to a tube well or borehole A windlass cylinder around which a rope is wound to lift the bucket is mounted to the cover slab of the tube well A cylindrical bucket is lowered down a casing in the well The bottom of the bucket has a valve that opens on contact with the water as the bucket is lowered It closes when the bucket is pulled up keeping the water inside A well cap and the fact that the bucket is stored in the casing reduce the risk of contamination A reduction in the retention time of water in the well casing ensures that any contamination that pollutes the well is rapidly removed However this system does not provide a high level of service Rope and Washer Pumps The rope and washer pump is not commonly known in South Africa but is used extensively in South America The pump consists of a single loop of chain or rope running over a winding wheel Small rubber or plastic washers of approximately 20 millimetres in diameter are attached to the chain at approximately one metre intervals On the upward journey the chain passes through a pipe The washers form a seal with the pipe and water is lifted The head of the pump should be sealed to prevent contaminants entering the well from the
62. ing sound decisions It is intended to give readers an introduction to the range of appropriate solutions available and to provide information on where and how different technologies solutions will be suited to different situations For more detailed information see the reference documentation starting on page 95 How to use the Guide Sections 1 3 contain stand alone information on a range of appropriate technical solutions with respect to Water supply technologies Sources of power for pumps and e Sanitation technologies 5 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Each technology is covered in broad terms and information under each technology includes What the technology is and how it works Requirements Institutional support Capital needs Operation and maintenance Advantages and disadvantages of the technology Experience as regards practical implementation OO Section 4 focuses on solutions for the control of water supply and payment options and is dealt with differently from sections 1 3 Itis divided into two sub sections Communal standpipes e Individual household connections Information under the sub sections is explored in terms of technologies for the control of water supply and loss and the various payment options available Section 5 provides additional information in the form of a description of the various pumps available and water treatmen
63. learer water can then be taken from the top of the container or the water can be carefully transferred to another container and the procedure repeated before the water is used 89 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Municipal Level Treatment Municipal water supplies are treated to change the attributes of the water source in order to make the water more acceptable for use These attributes include gt gt The clarity or turbidity of the water The colour of the water The taste odour of the water The hardness of the water The chemical content of the water The bacterial content of the water A treatment works normally has a series of unit processes Each unit process may contribute towards the removal of more than one substance Some substances may require more than one unit process for their removal A complete treatment process consists of a cost effective combination of unit processes that will provide water of an acceptable quality 90 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Table 1 Municipal water supply treatment Clarity Turbidity Water may contain suspended or very fine dispersed particles such as silt or plant residues that cause it to be murky Treatment method Suspended particles are removed by filtration Fine dispersed particles also called colloids pass through a normal fi
64. lter They are normally coagulated flocculated to form larger particles flocs before the filter Colour The colour of water can arise naturally or can be caused by pollution Natural colour such as that found in the brown waters of the Cape is caused by plant residues and is harmless Small amounts of iron and mangenese that occur naturally can also cause colour Colour arising from industrial pollution may spell danger Natural colour can be removed by coagulation flocculation followed by filtration Similarly colour resulting from pollution can be removed but careful monitoring and expert advice is needed Iron and manganese may need aeration prior to coagulation Taste Odour Taste is affected by dissolved gases chemicalsand residues from plant and other materials Aeration can be used to eliminate dissolved gases The removal of excess salts requires advanced treatment procedures such as those discussed under desalination Organic substances can be removed by coagulation flocculation and filtration with absorbtion on activated carbon for really persistent substances Hardness Dissolved calcium and magnesium salts in the water cause hardness Hardness increases the amount of soap needed to give lather and results in deposits in geysers and kettles Softening processes should be used such as adding sodium carbonate or using ion exchangers Changing the Chemical Content As discussed u
65. lume and low head pumping requirements This is generally implemented in areas where there is no electrical grid For larger pumping requirements solar or wind power is expensive Solar power for instance is only economical for pumping requirements of approximately 20 kilolitres per day to a 40 meter head Wind can be harnessed via windmills direct or wind generators indirect Solar energy is harnessed through solar panels Animals such as cattle or donkeys can be used to power pumps Such installations use a gearbox with a high ratio so that for every time the animal walks around the well the pump turns many more times This is suitable for high volume low head pumps for example pumping water out of a river to irrigate an adjacent field Hand pumps and foot pumps are reliant on people to drive them The most common drivers are electric motors These can be run off three phase power at 420 volts or single phase power at 210 volts Three phase motors are more economical for medium and large pumping installations typically with less than one kilowatt power requirement Virtually all electric motors suited for pumping use alternating current AC 84 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Electric motors have to be controlled by a set of electrical controls and switches These include safety devices that are needed to protect the pump and motor from damage These typically protect the pump
66. ly morning for a two hour period The valve is activated electronically so that no manpower is required for the normal operation of the system The system requires a small diameter reticulation since peak demand is reduced reticulation with individual household connections and the installation of a household storage tank The unit is installed on a small platform to allow space for the placing of containers underneath Support is required to operate and maintain the supply system The tank must be checked periodically to ensure the float valve has not been removed The advantages and disadvantages of this system are very similar to the trickle feed system The only difference is that this system is better adapted to prevent potential abuse Ethekwini Durban has piloted this technology extensively The municipality has made many modifications to ensure an optimum service It is currently supplying 30 000 households The valve opens around 2 a m and closes at 4 a m The household tanks fills up for a day 79 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Arrear Billed Mechanical Meters In this system each household has a water connection with a meter The water authority or municipality is responsible for the reading of meters at regular intervals and for billing the user The advantages include that a rising block tariff can be instituted The disadvantages include that if a leak occurs v
67. n Coagulation can be used to improve the chemical quality of water Further it can be used to treat micro organisms and water with a high turbidity high TDS The coagulant causes the fine particles to form larger particles flocs which then settle to the bottom of the tank and can be removed Defluoridation Fluoride can be removed from water using activated alumina or bone char and ion exchange A high intake of fluoride can cause tooth staining and hardening of the bones making them brittle Desalination Desalination reduces the level of dissolved solids in water This is important in areas where borehole waters have a high salinity brackish water and where the possibility of finding other affordable sources of water is low The processes that can be used for desalination include ion exchange electrodialysis reverse osmosis distillation and chemical precipitation Distillation Energy is applied to the brackish water high total dissolved solids to form water vapour leaving dissolved salts behind and the vapour is condensed to form pure water with low total dissolved solids Solar energy can be used to produce water vapour and this process is known as solar distillation or solar still Electrodialysis Electrodialysis uses membrane technology but the driving force in this case is electrical potential Water passes through electrically charged membrane pairs Dissolved solids are then removed from the water This process can be used t
68. n manage on going operation and maintenance 73 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Mechanical Pre Payment Dispensing M eter This meter controls the amount of water that a consumer can use The tokens must either be purchased or if a free basic water policy isin place given to the consumer If people do not have the correct size container water may be wasted but research has shown that this is less than if taps are left open The mechanical units are more expensive than electronic dispensers but their operation and maintenance is not as complex This allows community members to play a key role However some outside assistance is required Electrical Pre Payment Dispensing M eter This meter controls the amount of water that a consumer can use The credits on the coupons must either be purchased or if the free basic water policy is in place given to the consumer The electrical dispensers are cheaper to install than the mechanical ones however their operation and maintenance is more complex In the capital cost allowance must be made for the equipment to recharge coupons with credit It is difficult for community members to get involved These meters are more suitable for urban and peri urban areas Specialist assistance is needed for operation and maintenance 74 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Payment systems for communal sta
69. ncy b Making operational or behavioral changes based on the data analyses Groundwater monitoring Groundwater monitoring forms part of the groundwater management function Specifically it includes data collection and capture Boreholes need to be properly equipped in order to make monitoring possible A description of all the necessary tools for groundwater monitoring is described in the Toolkit for Water Services Groundwater monitoring tools Tools used in monitoring groundwater like a water level meter a flow meter a logbook and computer software 100 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Observation or monitoring borehole A borehole used to measure changes in groundwater levels often in response to a nearby pumping borehole and or to monitor changes in water quality either through the collection of water samples or by means of a down the hole electronic sensor Piezometer tube A tube manometer usually a plastic pipe having a diameter of 15 to 25 millimetres which is inserted into a borehole with the pump so that groundwater levels can be measured using a dip meter or electronic sensor Water board Defined by the Water Services Act 1997 as an organ of state established or regarded as having been established in terms of this Act to perform as its primary activity a public function and the Act further states that the primary activity of a water board is to
70. nder colour taste odour and hardness water can dissolve most substances The natural inorganic salts when seen as a group are normally referred to as the TDS of the water High concentrations of these salts make the water brakish and are removed through desalination Pollution arising from human activities such as mining industry and agriculture may give rise to certain harmful chemicals in the water that need to be removed Arsenic fluoride and nitrates are naturally occurring substances that may require removal when present in high concentrations Desalination processes such a reverse osmosis electrodialysis distillation and ion exchanges as discussed below are suitable for removing TDS The removal of specific toxic substances arising from natural causes or pollution needs special advice Reducing the Bacterial Content of Water M ost surface waters and some ground water contain bacteria some of which may be harmful to human health 91 Bacteria are removed by the disinfection processes that are discussed below Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Treatment processes include Chemical Stabilisation Chemical stabilisation is achieved through the addition of chemicals such as lime or carbon dioxide This is used to protect pipelines and fixtures from chemical scale hard deposits on the inside of pipes kettles etc and corrosion Coagulation Flocculatio
71. ndpipes A number of payment systems are available to recover the tariff from the consumer No payments are collected One option is not to charge community members for water usage on standpipes If water consumption is kept low through the carrying of water to the household then most households will use less than the free basic water amount of 6000 litres of water per household per month This saves costs on collecting money and on the installation of pre payment meters However problems may arise with water loss unless control mechanisms are in place A flat rate is collected The flat rate system works along the following lines A fixed amount is charged per household Accounts need to be sent out regularly monthly or quarterly A payment point must be established and payments reconciled against accounts and Credit control must be enforced The benefits of this system are that it is easy to administer and that there are no overheads for meter reading However there are also limitations The system can be viewed as unfair because users who live in close proximity to the tap usually use more water and yet they pay the same amount Problems may arise with water loss unless control mechanisms are in place Water kiosks Vendor system This system relies on a water vendor to sell water from their own metered connection to consumers The system either uses Coupons where a coupon worth a set amount is bought from the muni
72. nning are noted quickly by a temporary shortage of water and The system promotes greater awareness of water use as only a set amount is available each day There are also a number of limitations e Households are limited to a maximum daily amount that cannot be changed e Itis not possible to put a pressure hose on the outlet to wash a car or water the garden The temperature of the water in the tank rises on warm days especially if it positioned in the sun and e Leaks in the reticulation are difficult to detect using traditional methods such as the low night flow method Successful pilot trickle feed schemes have been implemented in Limpopo and KwaZulu Natal The technology has been implemented internationally in New Zealand and South America 78 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Ethekwini D urban Tank System This system is similar to the trickle feed system but there are also some important differences The Durban Tank system comprises of a 200 litre tank installed in every household A maximum of 200 litres is delivered every day When the tank is full a float valve closes off the inlet If the tank is not empty before filling commences then less than 200 litres will be delivered To minimise abuse of the system including householders bypassing tanks making illegal connections etc and to minimise reticulation losses the reticulation is only charged during the ear
73. nto the aquifer This is after the water has been filtered to ensure the removal of sediment Artificial recharge requirements Requirements include that the aquifer must be unconfined and extensive enough to provide storage When using infiltration basins the surface soils must be permeable enough to ensure a good rate of infiltration Water quality Artificial groundwater recharge can improve groundwater quality if the groundwater has a high percentage of dissolved solids in it and the surface water has a lower concentration H owever the quality of the recharge water should be monitored to prevent the injection of contaminants into the aquifer system 24 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Insitutional support Professional expertise is needed for the planning of an artificial recharge scheme including the determination of a suitable site and the design of run off conservation mechanisms Further a professional geochemical investigation to assess clogging potential and water treatment needs may be required This is if the groundwater or the recharge water does not meet drinking water standards Capital requirements Costs are associated with Water treatment ranging from basic filtration to complex systems The drilling of injection boreholes and The building of infiltration basins O peration and maintenance Operation and maintenance includes Periodic scrapin
74. o treat water with high concentrations of TDS chloride potassium sodium and sulphate Filtration Water is passed through a filter to improve quality Simple inexpensive systems can reduce turbidity More sophisticated systems can also remove some contaminants The filtration method may not remove all micro organisms so disinfection is required after filtration to ensure that the water is safe for drinking 92 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation lon Exchange lon exchange is achieved using an ion exchange resin The undesirable cat ions or anions in the water are exchanged for ions found within the resin as the water passes through it The resins have a limited capacity to exchange ions and when this is exhausted the resin must be regenerated using a brine solution The ion exchange process can be used to soften hard water for desalination reduction of TDS and for the chemical treatment of water i e for the removal of fluoride nitrate iron etc The ion exchange process can also be used at a household level This however can be very expensive Mixed O xidant Gases Generated On Site for Disinfection MOGGOD The MOGGOD process uses normal table salt to manufacture a chlorine equivalent An electric current is passed through the salt The chlorine that results is then used to disinfect the water supply Nitrate Removal Nitrate can be removed from water using ion exchange reverse osmosis
75. oakaway No decomposition happens in the vault therefore there is no smell and a vent pipe is not required On a monthly basis the dehydrated material is removed and composted to destroy pathogens The material can be composted on site or bagged and taken to a central composting facility With on site composting it is recommended that the user wait a year before using the compost With a centrally run and more controlled facility this can be reduced to two months Urine diversion dehydrating toilet requirements The faecal matter must be kept dry in the pit Moisture control is vital for the proper functioning of the system There must be sufficient space on the property for the compost to be used or the compost must be collected 65 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Groundwater and the system There is little threat of groundwater pollution The urine is disposed of in the root zone This means that plants can absorb the nitrates Water requirements This toilet has no water requirements for effective functioning Greywater This toilet cannot accept greywater Greywater must be disposed of in a soakaway or used for garden irrigation Level of comfort The toilet can be placed inside the house Further the closed vault without a vent pipe prevents unpleasant draughts whilst sitting on the pedestal Insitutional support The household can construct and maintain the toilet with
76. oduction to the Guide The need for appropriate solutions South Africa is one of the 30 most water scarce countries on the planet In line with our need to use our nation s limited water resources to achieve a better life for all Cabinet approved South Africa s first National Water Resource Strategy in September 2004 This is in accordance with the requirements of the National Water Policy 1997 and the N ational Water Act 1998 To ensure that the Strategy is achieved it is essential that appropriate solutions are implemented for sustainable services Every water or sanitation scheme has a unique set characteristics relating to e water resources water demand location in relation to support services acceptability to users affordability institutional arrangements 6 Each scheme therefore requires a solution appropriate to these characteristics This will ensure that water services are operated effectively and efficiently to be financially viable and to honour the services delivery agreement Strategic Framework for Water Services 2003 Remote communities low income settlements and water scarce areas of the country present the greatest challenges in finding appropriate solutions and they are often very different from solutions implemented in high income urban settlements Why this Guide The Department of Water Affairs and Forestry D WAF has developed this Guide to assist water services authorities in mak
77. on that can result during water extraction Unprotected wells present the highest risk of contamination This risk decreases as improvements are made Insitutional support With the correct information local artisans can dig wells without institutional support Also management of the well can be undertaken at household or community level Capital requirements Costs are associated with Payments to labour for the digging of the well M aterials for the lining Building of the protective collar Construction of the well cover and Construction of the drainage apron gt gt O peration and maintenance The well must be kept clean and in a sanitary condition Itis advisable to routinely add a small dose of household disinfectant such as Jik Water lifting devices whether a simple windlass and bucket or a more sophisticated pump must be maintained and or repaired Advantages of hand dug wells Advantages of hand dug wells include The risks of contamination are decreased as the well upgrades are increased The large diameter means that the well can act as a form of storage and e This system can provide a household level of service 13 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Limitations of hand dug wells Limitations of hand dug wells include e Children and animals can fall into unprotected wells and Depending on the level of improvement made to the hand dug
78. ore provide a more reliable water supply Limitations of tube wells Limitations of tube wells include They offer limited storage capacity for low yielding aquifers Problems with clogging of screens and scouring of sand from behind the screen may be encountered Ifthe raw water has a high iron or manganese content the abstraction screens will clog greatly reducing the yield e Access down the hole is not possible and They can only be constructed to a limited depth as compared to boreholes Practical experience Tube wells have been constructed along the coast in Northern KwaZulu Natal and in Zimbabwe 16 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Key references Ball Peter 2001 Drilled Wells Series of manuals on drinking water supply Volume 6 SKAT Still D A and Nash S R 2002 The Ubombo Family Wells Programme Paper presented at Water Institute of Southern Africa Biennial Conference Durban May 2002 Still DA Nash SR and MacCarthy Hand augered wells U seful contacts include O Department of Water Affair and Forestry O Groundwater Association of KwaZulu N atal O Partners in Development for hand augured shallow wells 17 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation W Spring Protection W hat is spring protection and how does it work A spring occurs where groundwater is forced to
79. ory Guide to Appropriate Solutions for Water Supply and Sanitation WE Alternating Twin Pit Composting Toilet Fossa Alterna Pet m iN Ti E T d Eo TE ag ALAN e ee SE Se ee W hat is a twin pit composting toilet and how does it work Two shallow pits are used alternately Solid and liquid waste drop into the pit and other matter such as soil vegetable matter leaves or grass are added at regular intervals to aid the decomposition process When the pit is three quarters full it is topped with a mixture of soil and leaves and is allowed to turn into compost over a period of six to twelve months During this time the alternative pit is used The time taken to fill the pit depends on the number of users The pits are small between 0 5 and 1 0 metres deep The humus produced can be used as a soil conditioner A vent pipe can be fitted to assist in the control of flies and odours The interior should be kept relatively dark Water can be used to wash down the chute of the pedestal but the contents of the pit should not become waterlogged Twin pit composting toilet requirements After each defecation organic matter or soil should be added Control of moisture of the waste is vital for proper operation of the system Groundwater and the system The pit cannot drain if the water table is high i e less than one metre from the surface In such cases alternative sanitation technologies for example urine di
80. out external support Institutional support is required if the compost has to be collected and transported for use elsewhere Capital requirements Capital costs include A structure this cost can be reduced if the toilet is placed inside an existing house Pedestal Vault and Composter The total cost depends on the materials used Costs can be reduced if the users do all or some of the work themselves O peration and maintenance Dehydrated faecal material must be removed to the composter and the compost heap must be maintained Alternatively the dehydrated faecal material must be removed to another location for composting 66 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Advantages of urine diversion dehydrating toilets Advantages include e The toilet can be constructed inside a house The compost may be used as a soil conditioner and the urine as a fertiliser re usable resource e The system can be constructed by the user with some guidance The vault may be built above ground if hard rock or high groundwater is encountered and e There are no problems associated with flies or smells as no decomposition takes place in the toilet Limitations of urine diversion dehydrating toilets Limitations include e The user must be willing to handle the dehydrated faecal matter on a regular basis and e The composter must be large enough to hold one year s amoun
81. r than hand excavation Practical experience Boreholes are common across South Africa Key references Ball Peter 2001 Drilled Wells Series of manuals on drinking water supply volume 6 SKAT Waterlines 1995 Technical Brief No 43 Simple drilling methods Vol 13 No 3 January Department of Water Affairs and Forestry 1997 Minimum Standards and Guidelines for Groundwater Resource Development for the Community Water Supply and Sanitation Programme First edition NORAD Project 3 and DWAF Standard Descriptions for Boreholes U seful contacts include O Department of Water Affair and Forestry O Groundwater Division of the Geological Society of South Africa O Borehole Water Association of Southern Africa O South African Drilling Association O Groundwater Association of KwaZulu N atal 11 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation WE Hand Dug Wells W hat is a hand dug well and how does it work This is a large diameter well dug by hand The diameter must be greater than 0 8 metres To enable two people to dig the well it should be 1 2 metres or more The diameter depth of the well and lining used if required can vary depending on the conditions at the site A lining prevents collapse of the sides of the well and can also protect the well from surface water entering and causing contamination Wells can be either protected or
82. r the first rains but to divert this run off The tank gutters pipes and screens must all be inspected and cleaned on a regular basis Advantages of rainwater harvesting Advantages of rainwater harvesting include The technology is easily and simply applied Water is collected at household level so there is ownership of the system Water is provided at the point where it is needed i e near the house The quality of the water is easily maintained Soil erosion and flooding around the house is reduced Gutters and storage tanks can be constructed from locally available material and The groundwater is less likely to be over exploited if it is used in conjunction with rainwater harvesting 6 O Limitations of rainwater harvesting Limitations of rainwater harvesting include e Rain is an unpredictable and irregular source of water e Large storage tanks may be required in areas where the dry season is long and e Itis difficult to attach guttering systems to circular or thatched roofs these require flexible guttering like impermeable shade cloth Practical experience Rainwater harvesting has been used for water supply for thousands of years It is still used extensively all over the world even in highly developed countries It has been used extensively in South Africa particularly where groundwater is poor and surface water is not perennial Key references Gould John 1999 Rainwater Harvesting Inform
83. reholes Hand Dug Wells Tube Wells Spring Protection Abstraction from a Sand Dam Artificial Recharge Water Supply Technologies O ther Rainwater Harvesting Cloud Mist Harvesting Greywater Recycling 2 Sources of Power for Pump Systems Introduction Sources of Power for Pumps Hand Pumps Solar Powered Pumps Wind Powered Pumps Diesel Powered Pumps Electric Pumps 3 Sanitation Technologies Introduction Sanitation Technologies Flush Toilet with Central Treatment Works Flush Toilet with Conservancy Tank Flush Toilet with Septic Tank and Soakaway Alternating Twin Pit Composting Toilet Fossa Alterna Urine Diversion Dehydrating Toilet Ventilated Improved Pit VIP Toilet 4 Technologies for the Control of Water Supply and Payment Systems Introduction Communal Standpipes Individual Households 36 37 38 38 41 44 47 49 51 52 53 53 56 59 62 65 69 71 72 73 LY 5 Background Information 83 Description of Pumps 84 Water Treatment 89 Household Level Treatment 89 Municipal Level Treatment 90 6 Additional References 95 Glossary and definitions 100 Acronyms CMA Catchment Management Agency CWSS Community Water Supply and Sanitation DWAF Department of Water Affairs and Forestry O amp M Operation and Maintenance SSA Support Services Agent WRM Water Resource Management W SA Water Services Authority W SDP Water Services Development Plan W SP Water Services Provider Intr
84. sh Toilet with Central Treatment Works W hat is a central treatment works and how does it work Waste from the toilet and greywater is flushed into a piped system that carries the sewage to a wastewater treatment works Greywater however can be separated out and utilised at household level At the works solids are separated from liquids pathogens are destroyed and solid waste is disposed of The treated water is then released back into the rivers The treatment works can vary from a simple pond system with no operators to a highly complex system requiring 24 hour support Waterborne sewerage requirements Waterborne sewage requires a household water connection a sewer reticulation and central treatment works Groundwater and the system Leakages if undetected may infiltrate the sub surface and result in groundwater contamination Further blockages and breakdowns which result in overflowing manholes can pollute both surface and groundwater 53 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water requirements A reliable 24 hour piped water supply is required Greywater The system can handle large quantities of greywater Level of comfort The toilet can be located inside the house A water trap prevents smells from the sewage entering the house Also there are no uncomfortable draughts whilst using the toilet Insitutional support Institutional support is required for t
85. stin L M 2000 Design construction operation and maintenance of VIP in South Africa WRC Report no 709 1 00 DWAF Sanitation Support 2001 Study Report on Management of Faecal Waste from On site Sanitation Systems in South Africa DWAF 2002 Sanitation for a Healthy Nation Sanitation Technology Options 70 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation 4 TECHNOLOGIES FORTHE CONTROL OF WATER SUPPLY AND PAYMENT OPTIONS INTRODUCTION COMMUNAL STANDPIPES Normal Tap Push Button Tap Mechanical Pre Payment Dispensing M eter Electrical Pre Payment Dispensing M eter Payment systems for communal standpipes INDIVIDUAL HOUSEHOLDS Electrical Pre Paid Dispensing M eter Trickle Feed System Ethekwini Durban Tank System Arrear Billed Mechanical M eters Payment systems for individual households 71 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Introduction This section covers the range of technologies available to control water supplies and to collect the tariff from the household Control of water losses is as important as cost recovery particularly in areas with communal standpipes or controlled delivery systems Poor management can result in losses higher than consumption In terms of payment options consideration must be given to where the householder can make payment collect coupons or recharge pre paid meter cards Tra
86. t of dehydrated faecal matter soil and toilet paper The size depends on the number of users Practical experience This technology is extensively in the Northern Cape and is being currently being implemented in Cape Town Key references DWAF Sanitation Support 2001 Study Report on Management of Faecal Waste from On site Sanitation Systems in South Africa DWAF 2002 Sanitation for a Healthy Nation Sanitation Technology Options 67 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation W Ventilated Improved Pit VIP Toilet W hat is a ventilated improved pit toilet and how does it work Waste drops into a large pit where the organic material decomposes and liquids percolate into the surrounding soil If the pit is sealed it becomes a conservancy tank which fills up quickly This is not a ventilated improved pit toilet O dours are removed and gases are vented by way of continuous airflow through the top structure down the pedestal and out via the vent pipe A darkened interior is maintained so that insects entering the pit are attracted to the light at the top of the vent pipe and are trapped by the fly screen The length of time taken to fill the pit depends on the number of users as well as the size of the pit If a large enough pit is provided three cubic metres or more and the system is well cared for by the householder life spans of 30 years are not uncommon
87. t options at household and municipal level Section 6 provides additional references to books journals and articles for in depth further reading for each solution Using the Guide to support use of the Decision Making Framework The Decision Making Framework for Municipalities N umber 7 3 in the Toolkit for Water Services is a stand alone flowchart available in poster and A4 formats It is for use by municipalities in making decisions for water supply and sanitation This Guide can be used as a reference when using the Decision Making Framework and where an explanation of the different solutions mentioned in the Framework is required 6 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation 1 WATER SUPPLY TECHNOLOGIES INTRODUCTION WATER SUPPLY TECHNOLOGIES GROUNDWATER Boreholes Hand Dug Wells Tube Wells Spring Protection Abstraction from a Sand Dam Artificial Recharge WATER SUPPLY TECHNOLOGIES OTHER Rainwater Harvesting Cloud Mist Harvesting Greywater Recycling 7 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Introduction The focus of this section is on access to the water resource source These sources are divided into Underground water resources sources e Atmospheric water resources sources and Recycling of the water resource source Underground water resources sources These comprise of both groundwater and springs
88. tes have been established in Atlantis Windhoek Polokwane O mdel supplying Henties Bay Swakopmund and Walvis Bay Karkams in Namaqualand and Calvinia Key references Murray E C 2004 Artificial groundwater recharge Wise water management for towns and cities WRC report no TT219 03 Murray E C and Tredoux G 1998 Artificial Recharge A technology for sustainable water resource development WRC Report no 842 1 98 Murray E C and Tredoux G 2002 Pilot artificial recharge schemes Testing sustainable water resource development in fractured aquifers WRC Report no 967 1 02 26 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water Supply Technologies Other WE Rainwater Harvesting W hat is a rainwater harvesting and how does it work Rainwater is collected from impermeable surfaces and led to storage tanks These surfaces include roofs and specially prepared ground and rock e Rainwater collected from roofs is channelled via gutters and pipes into storage tanks e Rainwater gathered from the ground is collected from sloping surfaces which are either compacted or covered with tiles concrete asphalt or plastic sheeting Water is directed to a storage tank Rock surface rainwater is collected from rocks that have been cleared of vegetation and soil Loose rocks and any fissures or fractures are sealed The water is prevented from running
89. that causes the pump to operate beyond its maximum rating the water will not move through the pump and the pump will overheat Positive displacement pumps which include reciprocating and rotary pumps Reciprocating pumps The typical example of a reciprocating positive displacement pump is a windmill or handpump which works by the raising and lowering of a set of rods which in turn operate a piston in a cylinder near the bottom of a well With each upstroke of the piston water is drawn into the cylinder from the well With each downstroke of the piston water is pushed from the cylinder up a riser pipe out of the well A pair of opposed valves at the bottom and the top of the cylinder are basic to the operation of such a pump Maintenance typically consists of keeping these valves and the piston seals in working order 85 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Rotary pumps The typical example of a rotary pump is a progressive cavity pump e g the Mono pump This kind of pump uses the rotation of a screw shaped element the rotor within a similarly shaped housing called the stator in order to lift water Unlike a centrifugal pump a rotary progressive cavity pump is not self limiting in terms of how much pressure it can produce and therefore it is more versatile However if the pump operates against a closed valve or if the pipeline is blocked the pump will keep on raising the pressure un
90. til either the pump or the pipeline is seriously damaged To prevent such damage an adequately sized pressure relief device must be incorporated into Notes on terms used to describe pumps and pumping operations Head The term head is used to mean the number of metres by which the water must be lifted The static head is the vertical distance between the level from which the water must be lifted to where it will be used or stored The dynamic head is the extra lift that is required to overcome friction in the pumping line Curves Figures or graphs are used to show how much water a given pump can lift per second or hour at different pumping heads and rotational speeds known as the head Capacity curves Other curves show how much power is required for different pump duties the power demand curves what the pump efficiency is at those duties the efficiency curves and from what level a pump can suck the water below its inlet without damaging itself the N et Positive Suction Head curve or NPSH curve These various figures are known as the pump curves Depending on the design of the pump and the materials from which it is made a pump may only be able to pump clean water or it may be able to handle muddy water or sewage Some pumps can even work with water containing gravel and small stones The latter types of pumps are heavier and more expensive relative to a clean water pump for which lighter cheaper components are acceptable
91. tion and on the completion of construction Water quality Water quality depends on the inherent properties of the groundwater when extracted threats of contamination during the extraction process and threats of contamination from the surrounding environment However it is important to remember that groundwater is still generally better quality than untreated surface water Usually minimum or no water treatment is required In some cases though the spring water source may be contaminated or have unacceptably high chemical concentrations This requires appropriate treatment Insitutional support Technical support is required to implement the scheme Such support would include flow measurements design of the spring protection system an environmental impact assessment and final construction However construction can be done using local skills and material Springs can be easily managed by a local person with minimal outside support Capital requirements Costs are associated with Cement River sand Pipes Stone concrete blocks or bricks and A plastic or ferro cement tank gt Spring protection can be carried out by a local artisan with minimal external support O peration and maintenance Control of all human and animal activities around the spring is necessary Regular maintenance of the perimeter fence if one exists is needed The spring area should be kept free of litter The growth of trees around t
92. to the motor require trained personnel Generally specialised tasks such as rewinding need to be performed Usually this expertise is only found in major centres Arrangements need to be in place for the payment of electricity accounts to prevent cut offs and back up must be ensured during breakdowns Capital requirements Capital costs include The motor e Transmission lines and e Transformers Operation and maintenance The operation and maintenance costs of an electric engine are less than those of a diesel engine Routine maintenance checks need to be done by trained personnel Advantages of electric pumps Advantages include that electric pumps are easier to operate and do not require as much maintenance as diesel pumps Electric pumps can be automated Limitations of electric pumps Limitations include e Rural areas are often subject to power cuts e Voltage fluctuations can hamper the productivity of the pump and A line fee is usually charged for connection whether electricity is used or not Practical experience Electric pumps are normally the first choice when grid electricity is available Key reference Baumann E 2000 Series of manuals on drinking water supply volume 7 Water lifting SKAT Switzerland 50 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation 3 SANITATION TECHNOLOGIES INTRODUCTION SANITATION TECHNOLOGIES Flush Toilet with Central
93. trical pre paid dispensing meters are used extensively However there have been a number of problems with maintenance especially in rural areas 77 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Trickle Feed System This is a low pressure system that delivers water constantly at a very low flow to a household storage tank The tanks have a small box fitted onto the inlet with a float valve controlling flow into the box The box has a very small hole towards the bottom through which water constantly trickles into the larger tank The flow is constant and is determined by the size of the hole in the inner tank and by the height of the water above the hole which is constant under normal conditions The larger the hole in the inner tank the greater the flow or trickle into the main tank It is thus possible to regulate the maximum daily flow by choosing an appropriate size of trickle flow orifice The size of the hole is set by the water services provider according to a monthly flat rate and the specific daily amount of water delivered There are a number of advantages The buffer storage capacity means that the system as a whole has a lower peak demand and short term lapses in supply do not affect the household e The lower peak demand means that smaller pipes can be used Some storage is provided at the household level and therefore bulk storage can be reduced e Water losses or taps left ru
94. ubmitted Geojournal Olivier J 2002 Fog water harvesting along the West Coast of South Africa A feasibility study Water SA Vol 28 No 4 349 360 Olivier J and van Heerden J 1999 The South African fog water collection project Water Research Commission Report no 671 1 99 Olivier J and Rautenbach C J de W 2002 Implementation of fog water collection systems in South Africa Atmospheric Research 64 227 238 Olivier J and van Heerden J 2003 Implementation of an operational prototype fog water collection system Project implementation Water Research Commission Report no 902 1 02 32 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation WE Greywater Recycling a Er E o Bey at W hat is greywater recycling and how does it work Greywater refers to the water used for personal hygiene washing of clothes and washing dishes Instead of disposing of this water in a sewage system if one exists it can be recycled and used for garden irrigation This reduces the demand for fresh water for irrigation Greywater recycling requirements Pipes are required which channel the water from the bath shower basins and washing machine to a sump The water is then distributed manually or through a pump and sprinkler system onto the garden The garden must be of sufficient size to prevent a build up of salts or over irrigation Water quality Greywater contains chem
95. uctory Guide to Appropriate Solutions for Water Supply and Sanitation E Flush Toilet with Conservancy Tank W hat is a flush toilet with a conservancy tank and how does it work Waste from the toilet and greywater is flushed into a watertight tank The tank must be emptied on a regular basis by a tanker and the contents disposed of at a sewage treatment works The treatment works can vary from a simple pond system with no operators to a highly complex system requiring 24 hour support The waste treatment works separate the solids from the liquids remove pathogens and dispose of solid waste The treated water is then directed to a river The tank size and the frequency of emptying depend on both the number of people using the system and the quantity of greywater disposed of If greywater is separated out and utilised at household level the frequency of emptying the tank can be significantly reduced Conservancy tank requirements A household water connection is required The tank must be large enough to cater for the needs of the household Further provision must be made to empty the tank Groundwater and the system If the tank leaks and this goes undetected waste may infiltrate the sub surface resulting in groundwater contamination 56 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water requirements A reliable 24 hour piped water supply is required Greywater The system
96. unknown to the consumer However problems may arise from expensive capital and operation and maintenance costs No meter readings are required Payment is collected in arrears The meters are read by the water authority on a regular basis normally once a month or every quarter The consumer is then billed according to the amount of water used Bills are delivered to the consumer and the consumer must pay the municipality This method of billing can be adapted in a number of ways These include An invoice can be delivered by the meter reader saving on the cost of postage An invoice can be delivered and the money collected by the meter reader and A self billing payment system can be implemented at a centralised point Spot auditing and a penalty system for incorrect readings may be necessary here Costs are associated with reading and maintaining the meters and administering the billing collection of revenues and credit control 81 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Key references Hazelton D and Kondlo S Cost recovery for water schemes to developing urban communities A comparison of different approaches in the Umgeni Water planning area WRC No 521 1 98 Simes C E Lings R J and Tshivhase T 1993 Prepayment Water M etering for South Africa WRC Report no KV56 94 DWAF 1997 Implementing Prepayment Water Metering Systems Department of Water
97. urs when rainwater is harvested from larger surfaces such as rock faces Recycling of Greywater Greywater refers to household wastewater This includes water used for personal hygiene washing of clothes and washing dishes Instead of disposing of this water in a sewer system or septic tank it can be recycled and used for garden irrigation 8 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water Supply Technologies Groundwater W Boreholes pR nie I e pos an i TT re oO P eae JJ J aie J come mas Se et ee aS eee a a a ae ee ee ee a a Ngee oe to ae ten Tt rl a a a a ee ee omi ar S AA ai r Pi 2 E a TSP See ral ah ee a Saat ae i i G i n at a a al My ae ee ea 1 ea P J oa a en FN ob SF a mf fl fe et Eee Oe J oh ae i ee i Ae i he ee ON a op ee eee aa tay ee eo Te ey ae ee W hat is a borehole and how does it work In South Africa the definition of boreholes has evolved to mean a small diameter drilled hole using a drilling rig Boreholes are too small in diameter for a person to enter for either the construction or the maintenance of the hole Borehole diameters range from 101 millimetres to 318 millimetres 4 inches to 12 5 inches The standard drilling method is rotary percussion drilling in hard rock In soft sediments the standard method is mud rotary drilling The type of construction method used will depend on the expected ground con
98. vel costs can greatly add to the overall cost of the service For example in the major urban areas payment can be made by direct debit through checkouts at major supermarkets post offices etc The consumer only pays the transaction charge No extra travel or time costs are incurred However this is not the case in rural areas Travel and time costs for the payment of bills and collection of pensions are considerable Travel costs must be properly calculated as ultimately this has a major impact on what is an appropriate and sustainable institutional set up 72 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Communal Standpipes Communal standpipes are placed along roads and in public places Householders bring their containers to the standpipe They fill them and carry them home Research has shown that the biggest limitation to consumption is the physical act of carrying water to the house Asa result only between 100 and 125 litres are utilised per household per day To dispense water to the consumer a communal standpipe can be fitted with the following technologies A normal tap that the householder can open or close There is no limitation to the amount of water released A push button tap that releases a set amount of water e g push button taps in Durban that release exactly 25 litres of water e A mechanical pre payment dispensing metre A token is inserted which allows for the release of
99. version toilets are recommended 62 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Water requirements This toilet does not require water for effective functioning Greywater This toilet cannot accept greywater This must be disposed of in a soakaway or used for garden irrigation Level of comfort The toilet cannot be placed inside the house Insitutional support The household can construct the toilet without external support Institutional support is required if the compost has to be collected and transported for use elsewhere Otherwise the user can maintain the toilet with no institutional support Capital requirements Capital requirements are associated with Building a structure The pedestal and Digging the pits The total cost depends on the materials used Costs can be reduced if the users do all or some of the work themselves O peration and maintenance The addition of organic matter such as garden material and vegetable matter or soil will assist in the decomposition process The top structure and the pedestal must be alternated between the pits The humus must be excavated after six months to a year for further use or for the collection and transportation for use elsewhere Advantages of twin pit composting toilets Advantages include e Waste may be used as a soil conditioner The toilet can be built by the householder and The two pits used occupy a small ar
100. wback is that it is dependent on a functioning transmission system In isolated areas this can be problematic Also with electricity accounts are paid in arrears In a number of situations this has led to the generation of huge bills The responsible organisation then can not pay and the power supply is cut creating huge problems Finally electrical pumps need transmission lines to be reasonably close to keep the capital costs down In contrast diesel powered motors require fuel to be delivered to the engine A degree of logistical planning is therefore important But in smaller schemes it may be easier to manage the rate of consumption of diesel than electricity However if the cost of supplying diesel or electrical energy is too high then alternatives such as solar wind and human power need to be assessed 37 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation Sources of Power for Pumps ma Hand Pumps W hat is a hand pump and how does it work Hand pumps use human power to bring groundwater to the surface The action of the pump handle results in a column of water being lifted to the surface Since human effort is used to lift the water this is a major limiting factor Hand pump adaptations H uman powered pumps include foot pumps where a person uses their legs as opposed to their arms Also there are play pumps that look like merry go rounds Hand pump requirements These includ
101. well there is a risk of contamination Practical experience Hand dug wells have been used extensively in Southern Africa The most notable example is the Zimbabwean family wells programme In South Africa hand dug wells have been built in KwaZulu Natal Limpopo and the Eastern Cape Key references King Georgina 1996 Development of Shallow Wells on the Zululand Coastal Plain DWAF Directorate Geohydrology KwaZulu N atal Watt S B and Wood W E 1979 Hand dug wells and their construction Intermediate Technology Publications London 14 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation E Tube Wells BU fee ao ed ae EAF A MA Sa i W hat is a tube well and how does it work In South Africa tube wells refer to small diameter holes constructed in soft formations using a hand auger Tube well diameters can range from 60 millimetres to 170 millimetres The water is brought to the surface by a pump or a small diameter bucket or bailer Tube well requirements The depth of tube wells should accommodate seasonal or annual fluctuations in water levels This is to ensure that the tube well does not go dry when the water table is low The optimum diameter of the tube well should be determined taking into account the anticipated yield the demand and the extraction method used The tube well should be cased from top to bottom and the casing should includ
102. witzerland Pearson l Weaver J and Ravenscroft P 2003 The reliability of small spring water supply systems for community supply projects Water Research Commission Report No 859 1 03 20 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation WE Abstraction from a Sand Dam W hat is sand dam abstraction and how does it work Groundwater can be collected from sandy riverbeds when the river is dry but the sand is still saturated Sand dams can also be constructed artificially by constructing a weir in the riverbed and allowing the area behind the weir to fill with sand Larger sand reservoirs should be developed over time by raising the wall in stages If the wall is raised too rapidly an accumulation of silt and clay can occur in the dam basin affecting water quality Water is usually abstracted through the construction of horizontal infiltration drainpipes or galleries The infiltration galleries are usually constructed perpendicular to the groundwater flow The pipes have slots or perforations that allow the groundwater to enter and screens to prevent or minimise the intake of sand They can be made of concrete stainless steel or PVC The pipes are placed in the riverbed by hand or mechanically The water that enters the pipes is drained to a collector well and abstracted through pumping Sand dam abstraction requirements A catchment with a significant percentage of coars
103. y Rainwater harvested from catchments other than the roof is not recommended for drinking purposes unless the water is treated first However this water can be used for washing and watering of plants and animal watering Rainwater quality from roofs can be improved by the inclusion of a coarse screen between the guttering and the delivery pipe Further improvements can include a fine screen between the delivery pipe and the tank a lid on the tank a first flush system that sends the initial run off to waste and the use of suitable roofing material Water quality can be poor in areas experiencing significant air pollution However this is usually not a threat in rural areas Insitutional support The householder can undertake installation of a roof rainwater harvesting system with no outside advice or assistance A ground or rock face rainwater harvesting system might require external support due to the scale of the construction Both systems can be constructed using local materials and artisans Capital requirements Costs are associated with The roof cleared rock face or prepared ground surface The guttering system downpipes or collection wall Filters and Storage tanks 28 Introductory Guide to Appropriate Solutions for Water Supply and Sanitation O peration and maintenance If it has not rained for a long time the roof must be cleaned before rainwater is collected Another option is to wait fo

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