Water for Bukora and Ndego Water Security Issues in Rwandan Resettlement Villages

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1 Water for Bukora and Ndego Water Security Issues in Rwandan Resettlement Villages Hans Hartung and Caritas Mukankusi, fakt, Stuttgart, Germany, 1. The situation 1.1 Setting Following cessation of the war in Rwanda and the genocide in 1994, providing shelter for returnees was a top priority. New land areas with limited water resources had to be used for the resettlement schemes of refugees coming back from neighbouring countries. In this paper we are concerned with 2 resettlement areas near Rusoma on the border to Tanzania: - Bukora, with a total of households. So far 369 houses have been equipped with rainwater harvesting systems. - Ndego resettlement area has 1349 households, out of which 988 have rainwater harvesting systems. All in all we have households with a rainwater harvesting system of about households in total. 1.2 Water situation Underlying granite rock indicates little potential for sufficient deep groundwater. Shallow groundwater may be available at a few selected sites. There is a spring at 17 km distance from Bukora of limited and varying capacity. A pipeline from this spring to standposts in each sector of Bukora village forms the common water supply; but the taps are very often dry! There is the Akagera river as a permanent surface water source; the shortest distance is 3 km at Bukora, most of the houses are much farther away. Long-term rainfall is around 850 mm with a bimodal pattern (2 rainy seasons), with only minimal rainfall during the months of February, June, July and August. 1.3 Rainwater tanks The houses in the resettlement villages have a total usable roof of appr. 51 m 2 of which only 50% is used for rainwater harvesting. The rainwater systems were built in an emergency situation, when thousands of people moved across the borders to Rwanda and had to be settled within a short period. Water was scarce and the use of rainwater was considered as a partial solution, the idea coming from returnees who had seen such systems. But no tradition nor experience was available and the rainwater harvesting systems were built without detailed investigations. The rainwater systems now in place consist of: - a gutter, bent of corrugated iron - a downpipe consisting of an elbow and pieces of 100 mm PVC piping - a storage tank (bamboo basket and chicken wire as reinforcement), covered with cement mortar and made water tight with water proof cement. The

2 storage tank sits on a stone foundation, is jar shaped, appr. 1,25m high and has an outer diameter of appr. 1 m. The wall thickness is varying, generally around 6 cm. All tanks are slightly different, depending on the varying bamboo baskets used for reinforcing. The volume of an average tank is 600 l only! The tank has: - a wooden cover (not fitting very tightly on to the tank) - an outlet with a tap and finally - a cleaning outlet closed with a ¾ plug. Material cost for one system without the house-roof are given (prices taken from an estimate of 166 systems in Ndego I): Materials from outside (Kigali): US$ 97,- Local materials US$ 20,- Gutters US$ 13,- Connection pipes US$ 30,- Labour US$ 64,- Total US$ 224,- The costs for these tanks are very high (373 US$/m 3 of storage capacity, including guttering and piping), considering the relatively small volume of the tanks! The only possible explanation could be the emergency situation at the time when the systems were built! Tank costs depend largely on material costs, mainly cement. Tank costs from neighbouring Kenya and Uganda are quoted (personal communication) as around 40 US$/ m 3 (guttering and piping not included, non-skilled labour provided free of charge). 2. Elements of water security The users point of view is considered here. 2.1 Availability 1 Water availability (resource aspect of water) is a function of - supply, in our situation of various sources: rain, spring flow and river flow and - spatial distribution (rain collected in tanks, piped water in tapstands and the river flowing in the vicinity). Rainwater is obviously only available after the rains. Due to the limited storage volume of the tanks, the water supply will last an average of two weeks. The piped water supply (fed from spring water) in most sectors of Bukora is very restricted. It is available most of the times just one day per week: e.g. 4 out of 21 days surveyed in October and 6 out of 28 days surveyed in November The last resort (if no other possibility remains) at both locations (Bukora and Ndego) is water from the river Akagera, at a distance of 3 km for the ones living closest to the river. Water is available there throughout the year, but not of safe drinking water quality. 1 The concept of water security discussed under availability, access and usage apects is taken from: P.Webb, M.Iskandarani, Water Insecurity and the Poor, ZEF Discussion Papers on Development Policy, Bonn, October 1998

3 2.2 Water access Water access refers to household water as a commodity (commodity aspect of water). This is partly determined by modes of distribution (see chapter 2.1) and partly by effective demand (how much a household can actually "take home"). Access to rainwater is restricted to those who own a tank which is connected to the house. Of the 16 households surveyed in Bukora and Ndego settlements, 3 of them (located in Ndego) had no rainwater tanks. Three other households in Ndego never used water from the water supply, apparently because of distance! Other than that, access is restricted by the availability both of rainwater and the piped water supply, working only intermittently. Cost consideration don not play a role as there are no direct water charges on the water taken from the mains supply. 2.3 Water use Water use relates to individual entitlements, i.e. water as a public and private good (entitlement aspect of water). Water quantity used per person and day in the different households changes significantly between households but stays the same in these households over the months: Oct. Nov. Dec. Bukora (l/p/d) 10,9 19,5 9,7 20,2 10,1 20,5 Ndego (l/p/d) (4,9) 7,4 17,7 7,9 22,8 6,8 22,9 Jan Feb. March April Bukora (l/p/d) 8,9 16,8 6,7 11,9 8,0 13,2 8,1 13,0 Ndego (l/p/d) 6,7 16,1 5,7 19,1 5,7 15,8 5,7 16,1 Water from the piped water supply will be used whenever it is available (on average around once a week). Water is usually not stored overnight but used up and new water is collected the next day. The average daily consumption from the piped water supply is roughly double the amount of the other water sources, rainwater and river water (when it is available). It has been found, that there is hardly any differentiation of water use coming from the different water sources. If rainwater is available, it will be the first choice and is used for all purposes until it is finished. Average percentage of rain water to total water use of those households with rainwater tanks: Oct. Nov Dec. Jan. Feb. March April Bukora 39% 76% 74% 47% 4% 64% 65% Ndego 85% 94% 96% 76% 0% 51% 60% Average daily water consumption from rain or river are more or less equal.

4 Differentiated acc. to use, the picture does not change much between the households in Bukora: Water use for Drinking/cooking 39% Hygiene/washing face, 40% hands, etc. Washing cloths 21% There was only one household using consistently water for other purposes: (animals, gardening) which amounted to about 25% of its total water use. One household used a small amount for these purposes once in a while. 3. Rainwater harvesting as an appropriate solution The standard practise of conventional engineering: only one water source for all possible uses is obsolete and not practical in many water scarce areas of the world.. Rainwater harvesting is a well introduced water source in some parts of the world having a long tradition in many of them 2. It has been neglected in the last few decades due to "modern" concepts of water supply. It currently finds renewed interest 3 as many water problems cannot be solved by conventional engineering and centralised approaches. There will always be people living in the hills or other areas without access to ground water or a possibility of connection to a water supply systems. Moreover the country has a very dispersed settlement pattern and a highly varied topography (country of a thousand hills). Due to a relatively high rainfall and a bimodal pattern, rainwater may play an important role in the future! But in order to make successful use of the advantages of rainwater harvesting, several basic considerations are necessary which have not been met in the situation described here: - structural stability of the tank. Bamboo is clearly not a durable reinforcement material! Evidence in Thailand 4 and other countries shows a short life span of bamboo reinforced tanks (5 years only quoted)! - storage volume of the tank. This depends on water demand, rainfall pattern, catchment area (roof size) and the availability of other water sources, but also on cost considerations. Sizing tanks to meet year round water demand of the household will certainly result in tanks too large to be economically affordable. In discussions with the tank owners and looking at various tank sizing methods, a storage capacity giving 30 days water was found suitable and would result in a tank size of 2,25 m 3. (15 l/p/d average consumption for a 5 member household). This size corresponds with standard tank sizes of 5m 3 in neighbouring countries with double roof size connected. 2 see e.g. work done by Agarwal, Anil et al. at CSE: 3 Proceedings of various International Conferences on Rainwater Catchment Systems 4 Gould, J. & Nissen-Petersen, E., Rainwater Catchment Systems for Domestic Supply, IT Publications Ltd., London, 1999

5 - The cost of the tank is crucial if rainwater harvesting is to be replicated further. This is certainly impossible with the high cost of the tank as quoted above (see chapter 1.3). But careful design with minimising material input like in Kenya has shown that costs can come down so that replication is possible! - Not much experience in rainwater harvesting exists so far in Rwanda much in contrast to the neighbouring countries Kenya or Uganda. Experience in setting up larger programmes as the one described is absolutely necessary and will optimise the funds available to get a higher degree of water security with the funds available. 4. Conclusion - Households in resettlement villages of Rwanda (as in many other places around the world) use multiple sources of water to meet their daily water demands. This fact has to be recognised when designing a water supply with limited funds and in a water scare environment - Rainwater plays a significant role in water supply of many households in the Rwandan settlement villages. Their rainwater harvesting system has a high value. In fact, neighbours without these facilities, see rainwater tanks as the best solution to ease their own water problems. - Water security is improved for those households with rainwater harvesting systems as - water availability is increased (one additional water source available), - improved access (physical and timely) to water, - that means that water use is at least possible with less constraint by walking long distances and still not getting good quality water (as from the river). - The design of rainwater harvesting system needs long-term experience. Storage tank construction and storage tank size can be optimised for maximum performance at minimal costs.