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<Sourcebook of Alternative Technologies for Freshwater Augumentation in Africa> 4.4 Spring Protection -- Mukono District, Uganda Introduction This study outlines the experiences gained during the implementation of spring protection programmes in the Mukono District of Uganda during the RUWASA project.Mukono is one of eight RUWASA project districts. The project aimed at improving the quality of life of the rural people through provision of water supply and promotion of sanitation and good hygiene. The project was identified in 1989, after the area was found to have harsh socio-economic and health conditions related to poorly developed water supplies and poor sanitation. The Mukono District lies between 32o 30' 30" and 33o 25' E, and latitudes 1o S and 1o 30' 30" N. The district is bounded by rivers on the east and west, Lake Victoria on the south, and Lake Kyoga on the north. The northern and cental parts of the Mukono District are underlain by undifferentiated gneiss of the basement complex. Recent sediments cover the contour boundary along the Nile. The southern parts are underlain by the Buganda Toro system (granitic and partly metamorphosed rocks) with basement complex (granite gneiss) exposures running in a northeasterly and southwesterly direction. From a monotonous flat topography in the north, the land changes to an undulating topography in the central parts, becoming hilly in the southern parts. The central parts have intermediate to thick overburden while the southern parts have very thick overburden in the Buganda Toro system areas. Rainfall varies from an average of 1 010 mm/year of rain in the northern half to 1 625 mm/year in the south. In 1991, the population was 750 000 people. The population was largely rural, with over 90% residing in the countryside. The majority of the people are self-employed in agriculture, growing food crops for domestic consumption with the surplus, if any, being sold to urban centres. The water and sanitation coverage in 1991 was about 10% and 30% of the population, respectively. It was estimated that water sources in the District were distributed as follows: 21% spring sourced, 43% shallow well sourced, and 36% borehole sourced. An inventory carried out in 1990, however, indicated a great number of protectable springs were located primarily in the south. Bacteriological tests showed that most of the springs were contaminated with faecal coliform bacteria. Technical Description The RUWASA spring protection project started in 1990. To date, about 800 springs have been protected in the Mukono District, benefiting an estimated 120 000 people. Protection activities start with source identification carried out by technical officers and the community. The criteria used to recommend a spring for protection include the following: (i) There should be at least 50 users, or about 10 households for the protection project to be economically viable. (ii) The spring should be perennial (confirmed by the users). (iii) The spring should have a flow greater than or equal to 10 l/min. (iv) There should be an adequate ground slope to provide ample drainage after construction of the retaining wall. The structure or retaining wall placed around the spring to be protected was originally constructed using stones and/or hard core. However, this was changed to concrete blocks, except in the case of the wing walls. This was because stone-masonry work was slower since the stones provided by most communities were small, and greater skills are needed by the mason to fit the stones into the wall. The skill of the masons may be a problem in the application of this technology elsewhere, especially with new masons. A 2½ inch galvanised iron pipe, used to protect the PVC outlet pipe, is cast into the retaining wall flush with the back and extended 50 mm at the front. At the back it is sealed off with cement mortar in order to avoid contact with the spring water. The 50 mm extension offers a good outlet, making the water easy to draw with the water buckets, but too small to make it an attraction for children to stand or sit on. It is important not to block off any spring eye. The work of clearing and digging the drain, with an appropriate notch shape and slope, that protects the spring from surface runoff and from back flows into the spring from the surrounding land surface, tends to be rather hard, and the communities tend to leave it uncompleted. Thus, they have been encouraged to complete work on the drains in one operation before any of the other work takes place. Extent of Use Natural springs have traditionally been used as a source of water, especially for domestic purposes. This project has improved the protection of such springs from pollution and improved the method of collecting and distributing the spring water. The technology, therefore, is acceptable, especially since the water acquired from the springs is softer than most deep borehole water. In a few cases, people have tried to resist the implementation of spring protection measures for fear that the eyes of the springs would disappear. These fears have been minimised by informing people about the causes of such disappearances, and by demonstrating examples of protected springs in neighbouring villages. The speed with which protection is implemented is affected during the rainy season because, during the planting season, people are busy in the fields. The rains also make some roads impassable, and the delivery of materials difficult. Operation and Maintenance The operation and maintenance of spring protection systems is well within the capacity of the local communities. Apart from keeping the area surrounding the spring tidy, maintenance consists of fencing sensitive areas, especially the area behind the retaining wall, and maintaining the storm water and runoff drains. Level of Involvement The responsibilities of the communities in each of the spring protection projects undertaken during the RUWASA project included: (a) selection of at least six members of the community to create the Water User Committee (WUC); (b) selection of two caretakers, one of whom must be a woman; (c) provision of manual labour and locally available materials for use in the protection project; and, (d) assisting in construction work on a self-help basis. Prior to the construction of the protection works, the community is responsible for clearing the drain and providing hard core, plaster-sand, and clay, where available. The responsibilities of the WUC include: (a) ensuring that individual members actively participate in the construction activities; (b) ensuring that the water sources are well looked after; (c) assisting and supervising the caretakers in carrying out their assigned duties; (d) proposing and enforcing by-laws, approved by the water users, regarding the use and up-keep of the village water supply; and, mobilising the community through the promotion of sanitation and hygiene education activities. The government or project manager produces guidelines for community based operations and maintenance activities; facilitates the training of caretakers and the WUC; and, pays for the skilled labour (masons and supervision), the transportation of materials to the site, and the acquisition of locally unavailable materials. Such materials may include cement, pipes, and lake sand. A further pilot project, using the private sector operators, started in 1995. The private contractors carry out the physical construction under government/district supervision, and with coordinating input from the village. Costs Protection of a spring is estimated to cost about $1 000. The value of the in kind community contribution (unskilled labour and locally available materials) is also estimated to average $1 000. Materials provided by the community are mainly sand, hard core and clay. Effectiveness of the Technology In general, the spring protection project was considered successful, although a high proportion of the springs continued to fall above the bacterial water standard. Unfortunately, during the 1993/94 drought, a large proportion of the protected springs were reported to have dried up. Notwithstanding, a study in May 1994 showed that, of 743 springs checked, 52% passed the minimum design yield criterion of 5 l/min, 42% were over 7.5 l/min criterion (the theoretical minimum to supply 20 litres per capita per day to 150 people over 8 hours, with 20% spillage), 34% were over the criterion of 10 1/min required for a spring to be protected, and 26% were completely dry. Over-night storage tanks are being constructed for low yielding springs. Given the community concerns regarding the drying of springs, additional investigations were made of the 26% of springs that have become dry. Some reasons for drying were found to include:
The studies showed that there was no difference in the protection provided to the springs in which polyethylene materials were used instead of clay as a seal. Because of the early concerns regarding the contamination of the springs, investigations into the water quality of the protected springs were also conducted. Water quality in the protected springs was generally satisfactory from a toxicological point of view as shown below. However, a survey carried out in the wet season showed that 3% exceeded the 50 Escherichia coli counts per 100 ml (EC/100 ml) criterion, 12% exceeded the 25 EC/100 ml criterion, and 52% exceeded the 3 EC/100 ml criterion. (Faecal coliform measurements were not made.) In 65% of cases investigated, there were higher levels of contamination at the household level than at source level, indicating that contamination occurred within the distribution system.
Other studies have suggested that springs located within less steep countryside had a higher percentage of better quality, in terms of both coliform counts and turbidities, than springs located in steeply sloped areas. It was also found that better the maintenance of the spring, such as maintaining the storm drainage, resulted in better the bacteriological water quality. Some communities have started growing vegetables to take advantage of the continually flowing spring water. Advantages The advantages offered through the use of spring protection technologies include:
Disadvantages The disadvantages of spring protection technologies include:
Further Development of the Technology Although the village inventory indicated a great number of protectable springs (3 200), only 40% met the project criteria for protection. Many reported springs were traditionally dug water holes in valley bottoms that could not be protected through this programme. Spring identification should be carried out during the dry season to minimise risk of protecting seasonally drying springs. Declines in the water table due to drops in rainfall were a major cause of drying springs. More detailed water resources studies are required to document the relationship between rainfall (seasonal and annual variations) and spring yields. In the meantime, the minimum yield criterion for a spring to be considered for protection was revised from 10 l/min to 15 l/min, and , in the case of low yielding springs, construction of a storage tank to collect water overnight is being explored and should be considered. The work plan for construction of spring should take into account the seasons (e.g., the demand for labour during the planting season). Human activity in the catchment area of a spring has a big affect, especially on the bacteriological quality of the water. Preferably, 30 m around and upgradient of a spring should be kept free of human activity to minimise the potential for contamination from this source. By-laws to this effect should be encouraged where possible. There is a need for improved and recorded observations on spring site features which might correlate with the vulnerability of the spring to pollution. Similarly, monitoring and record-keeping relative to the sensitivity of a spring to seasonal discharge changes would be desirable. Some general monitoring of subsequent performance of the spring would also provide valuable information with which to measure project success. Rural water quality guidelines should take into account the resources available and the coverage of public water supplies. In this case, if the project guidelines were strictly followed, 52% of the water sources which provide water to over 60 000 people would be condemned on the basis of excessive E. coli counts. Notwithstanding, hygiene education, especially the safe water chain, is important as the contamination level at the point of drinking in household is much higher than at the source. Information Sources DANIDA (Danish International Aid Agency) 1995. Project Document: RUWASA Phase II. DANIDA, Copenhagen. Geria, I. and UNICEF (United Nations International Childrens Emergency Fund) 1993. The Potential for Different Abstraction Technologies for Rural Water Supply in Uganda. Ministry of Natural Resources. Kruger, I. 1990. National Rural Water Supply Programme: Republic of Uganda. Nordic Consultancy Group. RUWASA East Uganda Project 1993. 1991-1992 Data And Experiences. Directorate of Water Development, Uganda. RUWASA East Uganda Project 1994a. Phase II Strategy Report. Directorate of Water Development, Uganda. RUWASA East Uganda Project 1994b. Status Report. Directorate of Water Development, Uganda.
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