|Water Manual for Refugee Situations (UNHCR, 1992, 160 p.)|
|10. Water distribution systems|
7. Valve boxes should always be built to protect control valves from undesirable tampering, which may upset the hydraulic behaviour of an entire water supply system or some of its components; valve boxes are to protect control valves - and the whole supply system - from this type of disturbance; they may be attached to other structures (e.g. storage tanks) or placed independently along the pipeline. They may be made from many materials, depending on local availability, but they should always be provided with a secure cover, adequate drainage, and a size large enough to allow easy operation and maintenance.
8. Whenever it becomes necessary to reduce hydrostatic pressures in gravity pipelines, break-pressure tanks are used. These tanks permit the flow to discharge into the atmosphere, thus reducing pressures to zero; a new static level is, therefore, established. Strategic placing of break-pressure tanks minimizes capital costs, as the need to use GI pipes or more expensive, higher grade plastic pipes is reduced (See 10.5). Cement masonry, concrete or any other suitable material may be used for their construction.
9. The most common water distribution facility used in refugee camps is the public distribution standpost or tapstand. These structures should be designed and built bearing in mind that no other component in the water supply system will suffer more abuse and that they should always be adapted to social and cultural needs of the beneficiary refugee population. This is particularly important in view of the fact that standposts are more than a physical structure; they will normally become a social gathering point where several day-to-day activities (water collection, clothes washing, bathing) will take place (See 6.29). This means that, as part of their design, enough attention should be paid to their location and to the additional facilities necessary to make them sanitary and attractive. The control of water wastage at standposts should also be given importance. Users should never fail to turn off the taps and constant maintenance should be ensured to avoid leaky or broken taps; self-closing, water saving taps have proven effective in this context and their installation in tap-stands should be encouraged (See 10.6). The use of prefabricated distribution standposts may be considered during emergency situations, especially if other system components, such as pumping sets, storage or filtration tanks, etc., are also being brought in as prefabricated packages or kits; these should, however, be of sturdy construction and should allow the use of water saving taps. No single standpost location is likely to meet all ideal requirements; selecting the most appropriate ones will always be a process of compromise. Standposts should be located in places where distances to water users are minimal; as a guideline, 200 metre distances are advisable for most refugee camps, while in less congested situations, such as in rural refugee settlements, a minimum distance of 500 metres may be acceptable. The need to drain away all waste water should also be given consideration; the costs for this drainage system may be substantially reduced by locating other service components, such as laundry or bath/shower facilities, in the vicinity of the standpost or by using some of this waste water (free of soap or detergents, please!) in fruit or vegetable garden irrigation. Water pressure at standposts should not be too high, never higher than 4 bars (40 metres); very low pressures should also be avoided (absolute minimum: 0.70 bars or 7 metres). While it would be desirable that a single tap would not be used by more than 20 beneficiaries on average, this figure could be as high as 100, depending on the characteristics of each particular refugee situation; to provide an appropriate coverage, multiple tap standposts may be constructed; common designs allow for the installation of 5 to 10 taps in each post.
10. The need to include appropriate washing/laundry facilities as a standard infrastructure component of a refugee camp is often overlooked. Washing cooking dishes and clothes is a basic need and, as such, should be appropriately covered by the camp infrastructure. If not, more wasteful, and perhaps less sanitary alternatives, will be developed by the refugees themselves. It is not possible to give general rules or guidelines for the design or construction of appropriate laundry or bathing facilities, as they should respond to the individual needs, as well as to cultural and religious practices of the refugee users. Therefore, their design should be entrusted to qualified engineers who should take into account cultural habits, sanitation requirements as well as the need to minimize water wastage.
11. In some circumstances, there will be a need to provide appropriate watering points for cattle (See 10.1) or for the filling of animal driven carts or water tankers (See 3.5). Adequate designs for these facilities are available in the literature. Their location (normally outside camp boundaries) should, as a rule, be away from refugee water supply standposts. These facilities should always be provided with appropriate access and efficient drainage facilities.