See Resources > Tools > Technical Standards for detailed information on design and construction of alternatives.
See: Community Water Supply: the Hand Pump Option. Saul Arlosoroff. The World Bank. 1987, 1998. This report investigates the cost-effectiveness and reliability of two water supply systems, ground water and hand pumps. It is based on the findings of UNDP/World Bank Hand Pumps projects, where thousands of hand pumps of many different designs have been field-tested by the projects to produce accurate and reliable results. In a second edition about half the entries have been updated to take account of new test data on the pumps concerned.
IN-HOUSE CONNECTION
Ultimately the goal of every utility and family is to have access to a safe and reliable water supply within the house. Although various options for in-house water supply may be provided the main feasture is access to piped water supply inside the house (full or partial pressure – See Case Example: Water Supply - Durban) accompanied by waterborne waste disposal facilities that could be on-site (septic tank, etc) or off-site (sewer network or communal wastewater collection or treatment facility).
Advantages:
Convenience of 24 hour access.
Higher water quality.
Customer satisfaction is generally high with this level of service.
Increased water quantity allows for improved health and hygiene.
Households have strong incentives to maintain their water-supply infrastructure.
Disadvantages:
May encourage wasteful usage, if metering and realistic pricing are not used.
Waste-water disposal cost cannot be ignored.
Possible sources of water: Utility network or localised point source or small piped network.
Management: Utility or other service provider meters and bills consumer on regular basis.
Implications: Consider long-term implications for sustainability or suitability for extension to improve service level: inefficiency or utilities operations leads to a vicious cycle of no water, inaccurate billing, non-payment, no maintenance, etc.
Piped systems require coordination and long-term planning to ensure sustainability.
Operation and maintenance requires adequate technical capacity and a system that provides spare parts and supplies.
Without adequate funding, system extensions will not keep pace with population growth.
Financing is often necessary to make up-front connection costs affordable for low-income households.
Lessons:
Options for pressure offered through tanks, bailiff, restrictor meters, etc. Allows household to monitor and control volumes consumed.
Deposits – reduces risk and provides security for utility but barrier to low-income household.
Non-payment usually a result of number of factors, e.g. domestic vending, irregular and inaccurate billing, etc.
Water supply network at minimum and standard level using communal facilities initially. The land subdivision pattern establishes the costs for the piped network - a more efficient land subdivision results in reduced costs to the municipality and the user, in both initial capital investment and long-term maintenance. See: Urbanization Primer. Horacio Caminos and Reinhard Goethert. MIT Press. 1983.
YARD TAP FOR A SINGLE FAMILY
A private tap in the yard provides many of the same benefits as an in-house connection. In certain communities—such as those with poor housing quality—yard taps may be the only household-level service option available.
Advantages:
Convenience of 24 hour access.
Customer satisfaction is generally high with this level of service.
Increased water quantity allows for improved health and hygiene.
Households have strong incentives to maintain their water-supply infrastructure.
Disadvantages:
Less control over usage.
Wastewater removal may require additional investment.
Potential for vandalism exists.
Possible sources of water: Utility network or localised point source or small piped network.
Management: Utility or other service provider meters and bills consumer on regular basis.
Implications: Consider long-term implications for sustainability or suitability for extension to improve service level: inefficiency of utility operations leads to a vicious cycle of no water, inaccurate billing, non-payment, no maintenance, etc.
Piped systems require coordination and long-term planning to ensure sustainability.
Operation and maintenance requires adequate technical capacity and a system that provides spare parts and supplies.
Without adequate funding, system extensions will not keep pace with population growth.
Financing is often necessary to make up-front connection costs affordable for low-income households.
YARD TAP FOR SEVERAL FAMILIES (shared multi family)
A shared yard tap is a compromise between in-house / single-family yard connections and community or public water points. It often is an affordable level of service nearest to households’ aspirations.
Advantages:
Convenient source of safe water supply.
Responsibility for tap maintenance shared among a small number of households.
Sharing capital costs helps resolve affordability problems for low-income households.
Disadvantages:
Possible disputes over tap sharing, especially where service is intermittent.
Non-payment by a single user may result in service disconnection for other households.
May encourage wasteful usage, if metering and realistic pricing are not used.
Wastewater removal may require additional investment.
Possible sources of water: Regional/ city utility network using groundwater or surface water (with or without treatment).
Management: Regional or municipal level service provider, small-scale private entrepreneur, NGO, or community.
Implications:
Piped systems require coordination and long-term planning to ensure sustainability.
Operation and maintenance requires adequate technical capacity and a supply system that provides spare parts and supplies.
Without adequate funding, system extensions will not keep pace with population growth.
Financing is often necessary to make up-front connection costs affordable for low-income households.
If households in the community receive different levels of service and a ‘social’ (increasing block) tariff is used, low-income households who share taps may incur higher prices per volume than higher income households with individual-level service.
PRIVATE POINT SOURCE
A private point source, such as a well or borehole, may serve one or a group of households, depending on the source’s ownership, as well as its regeneration capacity. For communities beyond the reach of piped networks, private point sources may be the principal level of service for most households. Where piped networks exist but are unreliable or inadequate, households often use private point sources to supplement their water supply, particularly for non-potable purposes such as washing and bathing.
Advantages:
Convenient source of water supply.
Incentive for good maintenance shared among a small number of households.
Complements municipal piped water systems that are unable to reach all households.
May be a less expensive water-supply option for low-income families.
Disadvantages:
Difficult to detect water quality problems.
Seasonal variations in supply may reduce reliability.
Possible disputes over tap sharing, especially where service is intermittent.
Possible sources of water:
Ground water, rain harvesting reservoirs, or possibly surface water.
Management:
Generally private-sector or household installation and management; possibly community managed.
Implications:
Where widespread water-quality problems exist, substantial public-education and technical assistance efforts may be needed to ensure safe use of water.
Household-level decisions on water use at point sources may affect the viability of larger water-supply systems, e.g., through groundwater depletion. See also externalities.
A long-standing tradition in many parts of the world, water vending is a water-supply system that generally has low capital and high labor costs. Vendors obtain water from a variety of sources—surface water, borewells, or even a piped network—and transport it to customers using carts, bicycles, or hand-carried buckets. Charges are typically based on the volume of water sold. Households who rely on vendors often are unable or unwilling to invest in improved water supply services such as wells or taps.
Advantages:
Convenient delivery of water at the doorstep. Delivery to the home avoids the fatigue of carrying water and the time wasted at supply points.
Households without access to piped water can still obtain minimum amounts of safe water for cooking and drinking.
Daily or weekly payment to vendors may be more manageable to low-income households as compared to a monthly water bill.
Water quality is generally satisfactory.
Supplies may be obtained at any time and a customer loyalty policy (contract between deliverer and customer) is sometimes drawn up to guarantee regular deliveries.
Greater flexibility of payment options, and possibility of obtaining service on credit. Customers face no up-front payment or connection fee. Cash payment is appropriate given the limited savings capacity of low-income households.
Home delivery saves people from being identified as poor.
Disadvantages:
Households generally pay by volume for vended water that far exceed those of a piped system.
Little/no regulation of water quality or pricing.
Availability of vended water may help government to rationalize the failure to provide improved water supply services.
High prices restrict customers to parsimonious consumption (a few liters per day): in general potable water is used exclusively for food and drink.
Possible sources of water:
Groundwater (e.g., bore wells, open wells), surface water sources (e.g., springs, rivers). Vendors might also re-sell water from public standposts or private connections to households without access to piped water.
Management:
Generally private sector (individual or small groups of entrepreneurs). Some vendors sell water only in the dry season when profits are higher.
Implications:
High unit price of vended water does not necessarily indicate excessive profits; whether vending represents a reasonable service at a fair price for the customer depends on the degree of competition among suppliers.
Vending creates a local, labor-intensive market that is generally seen as an interim solution for communities without access to piped water supply. Customer protection measures, such as promoting competition and regulating quality, must be designed carefully so as not to discourage entrepreneurs.
Allowing the re-sale of municipal water by vendors is generally viewed as a pro-poor strategy. However, if the utility charges vendors less than what it costs to provide them water, this arrangement can actually slow the extension of the piped network to un-served neighborhoods.
RAINWATER HARVESTING
The direct collection and use of rainwater for domestic and agricultural purposes is an ancient technique which is slowly becoming more accepted. In many parts of the world with relatively high rainfall spread throughout the year, rainwater harvesting provides an important source. In Africa interest is growing and there are many initiatives ongoing across the continent, and institutional use has been increasing in Africa. Low rural incomes are a major obstacle for investing in household rainwater tanks. However, the increasing use of impermeable roofing materials, the establishment of community-based revolving funds and significant support from many donor agencies (e.g. UNICEF, SIDA, DANIDA, and FINIDA) has helped increase access among rural Africans.
Roof collection is the preferred method, because ground water tends to be too dirty for human use. It is particularly useful for laundry use because of its 'softness'. Partial supply of water needs is the more common approach. The bigger the storage tank, the less dependent on evenly spaced rainfall, but at becomes more expensive and requires more space.
Criteria for success include appropriate training, good workmanship, quality control, and the need for developing mechanisms through which poor people can paid for systems gradually being adopted around the world.
Systems often do not operate at full capacity because of inadequate design and construction of guttering and other components of the delivery system. The most common problems relate to the size and slope of gutters and/or the limited utilization of the available collection area.
Advantages:
More convenient than water which needs to be carried
Offers independence from outside control
Few, no demands on public funds
Little impact on other water sources
Buffers storm runoff
Disadvantages:
Requires 'hard' roof to collect water, hence, can be costly
Requires spaced rainfall for best performance
Uncertain water quality and rarely tested
Requires space for storage on surface or underground
Taste sometimes unfavorable compared to mineral-rich groundwater
Difficult to collect sufficient amount for higher densities
Consider collecting water from rain, but container must be covered and clean.
COMMUNITY STANDPOST
Standposts - sometimes called standpipes - are small piped distribution systems that feed a limited number of public taps, each of which serves all households in the vicinity. Standposts can be an efficient means of water distribution in settlements with limited water resources; they are also often provided in low-income areas where it is believed that households cannot afford private connections.
Advantages:
Households without private connections or yard taps can still obtain minimum amounts of safe water for cooking and drinking.
Capital costs shared by a number of households.
Disadvantages:
Users face time and labor costs in queuing and carrying water to their homes.
Possibility of disputes over sharing, especially where service is intermittent.
Often only a small volume of water is available to each user.
Public water points may be vandalized.
Possible sources of water:
Groundwater, surface water, or rain water (with or without treatment).
Management:
Municipal water supply service provider, village or community management, or small-scale local private entrepreneur.
Implications:
Community standpipes are often provided free of charge to users, which is likely to undermine long-term sustainability. Under municipal or private-sector management, the use of volumetric charges (charges based on container size) requires an attendant or the use of coin-operated meters. Flat monthly fees may be unaffordable for low-income households and are less effective in encouraging conservation. Community management may take advantage of local norms to devise payment rules that are enforced through social pressures.
Water kiosks can be viewed as stationary vending locations, staffed by attendants, where water is distributed by the container. They differ from 'Community Standposts' in that water is sold and not free as generally is the case of community standposts. Water sold in kiosks may come directly from a piped network, or may be transported from a borewell or surface water source for re-sale to households. Kiosks can help increase access to safe supply in communities without access to a piped network, or where the proportion of households connected to the network is small.
Advantages:
Provides households without access to piped water an alternative source of potable supply with no up-front payment or connection fee.
Mobile kiosks can respond quickly to changes in demand among neighborhoods.
Daily or weekly payment to kiosk attendant may be more manageable to low-income households as compared to a monthly water bill.
If realistic pricing is used, per-unit charges encourage financial self-sufficiency.
Disadvantages:
Users face time and labor costs in queuing and carrying water to their homes.
Kiosk operating times may be inconvenient to some users.
Relatively high administrative and operation costs.
Possibly little/no regulation of water quality or pricing.
Possible sources of water:
Groundwater (borewells), surface water (springs), or rain water (with or without treatment).
Management:
Municipal water supply service provider, private sector, NGOs, or community groups.
Implications:
Kiosk placement must respond to customers’ preferences.
For private operators, customer protection measures (e.g., promoting competition and regulating quality) must be designed carefully so as not to discourage entrepreneurs.
Allowing the re-sale of municipal water by private kiosk operators is generally viewed as a pro-poor strategy. However, if the utility charges operators less than what it costs to provide them water, this arrangement can actually slow the extension of the piped network to un-served neighborhoods.
RESALE BY NEIGHBOURS
Resale by neighbours occurs in communities partly connected to municipal networks, where households with in-house or yard taps sell economic inequalities or utility inefficiencies restrict connections to all households.
Advantages:
Increases access to potable water without additional capital investment on the part of households or the service provider.
Convenient and generally reliable source of potable water for users.
Households with connections have strong incentives to maintain their water-supply infrastructure.
In most cases, a less expensive option for households than delivery by vendors.
Daily or weekly payment to neighbours may be more manageable to low-income households as compared to a monthly water bill.
Disadvantages:
Neighbours may restrict/eliminate vending without warning, especially during short or irregular supply.
Possibility of disagreements among neighbours over water supply.
Possible sources of water:
Regional or urban level utility network using ground or surface water.
Management:
Generally private entrepreneurs.
Implications:
In many locations, re-sale of municipally supplied water is prohibited, which limits the options for obtaining safe water, particularly for poor households.
Where a ‘social tariff’ (increasing block tariff) is used, low-income households who buy water from neighbours may incur higher prices per volume than higher income households with individual-level service.
Because it is generally the wealthier households in a community who obtain water connections, allowing these households to profit from re-sale to poorer neighbours might be viewed as exploitative. On the other hand, if low-income households have little chance of obtaining a private connection themselves in the short term, re-sale by neighbours provides competition for vendors—which can drive down prices and improve the quality of service for poor households.
