Sustainable Smallholder Land & Water Management Systems

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1 Sustainabe Smahoder Land & Water Management Systems Identifying promising smahoder water and and management systems, incuding soutions deveoped by poor communities. Evauating high potentia systems; finding ways to transfer them to hep other poor areas. Promoting the uptake of these innovations through increased institutiona capacity of nationa partners. 22 Research Themes: Integrated Water Management for Agricuture Sustainabe Smahoder Land & Water Management Systems Sustainabe Groundwater Management Water Resources Institutions & Poicies Water, Heath & Environment

2 Low-cost irrigation for poverty reduction An evauation of ow-head drip irrigation technoogies in Kenya S.N. Ngigi, J.N. Thome, D.W. Waweru, H.G. Bank Summary Unreiabe rainfa causes periodic droughts in Kenya. This unpredictabiity, couped with the ack of oca capacity to dea with the situation, creates a persistent threat of househod food insecurity in the region. Low-head drip irrigation technoogies were introduced to combat this probem and aeviate food insecurity for thousands of peope. First indications from a variety of research sources are that these technoogies are a formidabe poverty-fighting too. IWMI research evauated the ow-head drip systems most commony avaiabe in Kenya. The purpose of this research was to identify and address the technica constraints of the systems and to deveop practica recommendations for smahoder farmers, so that they can maximize the benefits of this technoogy. Low-head irrigation technoogies were introduced in Kenya in 1995 by Christian Mission Aid. The Kenyan Agricutura Research Institute (KARI) has been promoting the technoogy since Unti recenty, Kenyan smahoders, mosty women, strugged to maintain kitchen gardens, using hand-watering to cutivate vegetabes for their famiies. Hand-watering of vegetabe gardens is tedious and inefficient especiay where water is scarce. It requires many trips back and forth to the water source (which is often some distance away), and it does not deiver water down to the root zone (Reaves 1995). Rather than go through this tedious and time-consuming irrigation process, many peope chose to go without vegetabes in their diet during the dry season. Today, they use ow-head irrigation technoogies in the form of bucket drip kits to deiver water to their crops effectivey, with far ess effort and for a minimum cost. Hundreds of poor famiies that use bucket kits during the dry season have shown that it is possibe to produce enough vegetabes for their domestic use and even for sae (Lusaka 1999). Use of the drip kit is spreading rapidy in Kenya and the majority of drip users (some 70-80%) are women (Winrock 2000). Women do most of the gardening in Kenya, and woud often carry water from distant water sources to hand-water their vegetabes. 23

3 Low head drip irrigation technoogy: Advantages and disadvantages. Advantages Disadvantages Water saving a arge reduction in the amount of water needed for growing vegetabes Labor saving pots can be irrigated quicky, simpy by fiing the bucket Fewer disease probems, such a mod and powdery midew (funga), caused by soi spashing onto pant eaves (Baobab 1998) Low-cost the system is priced to fit poor farmers budgets Simpe to insta, operate and maintain Easy to adapt to meet farmers particuar needs; for exampe, Ouko (1998) reported that some farmers in the Suba district aong Lake Victoria, are fixing 30-m drip ines (rather than the usua 15 m) to arger 50-iter buckets to accommodate onger growing beds Breakage of the fiter pug due to britteness of the pastic used Less fexibiity in terms of emitter spacing and atera engths Easiy punctured by sharp objects if poory handed Cogging of some emitters Nonuniformity of emitter discharge aong the atera, especiay where and is not we eveed Lack of spare parts and inadequate extension services Leakage, especiay at bucket connections, if fittings are not done propery, i.e., if the hoe is bigger than the adapter; other causes of eakage are punctures, cracks. Insecurity: fear of theft if the system is instaed far from the house Pest attraction being the ony green spot, especiay during the proonged dry spes, insects, rodents, aphids, etc., find refuge in the drip gardens; porcupines in search of water have even been reported to puncture drip ines in the Suba district (Ouko 1998) Profitabe for sma-scae farmers enabing them to produce enough vegetabes for their famiies and for sae (Winrock 2000) Improved househod nutrition and incomes Drip kits do have disadvantages (see box) but the positive socioeconomic impacts seem to outweigh them. Farmers reported gross profit margins ranging between Ksh. 4,000-10,000 ($80-200) with a singe bucket kit per season, depending on the type of vegetabe (Winrock 2000), and between Ksh. 20,000-30,000 ($ ) per season with the 1/8 acre kit (Nyakwara et a. 2000; Winrock 2000). These kits enabe farmers to grow high-vaue crops, and they create empoyment opportunities in the rura areas. This adds up to a significant potentia for poverty aeviation. Take the case of Mrs. Mutai (KARI 1998). She is one of 150 women who were members of a group that started using drip irrigation in Edoret. The system was instaed in December Four months ater, she had aready sod enough vegetabes to invest in more ines and make her garden bigger. Another member of the women s group, Anne Butia, has sod Ksh 10,000 ($200) worth of vegetabes in three months from her tighty-fenced garden. Neighbors used to wak 10 kiometers to another district to buy vegetabes but now they buy them from her. She has used the extra income to pay schoo fees and buy cothes for her famiy. 24

4 These and other cases show that ow-head drip irrigation is proving to be a promising technoogy for responding to shortages of water and food in arid and semiarid areas. Lowhead drip irrigation technoogies promise improved food security and increased incomes at the househod eve, utimatey cuminating in a heathy nationa economy (Winrock 2000). Ndiritu (1999) goes further, saying that the bucket kit is the savation of our country, as it aows the poorest of the poor to produce vegetabes under conditions that previousy woud have ony produced starvation and death. Types of ow-head drip systems With ow-head drip irrigation the oversophisticated and overengineered contro eements used in the conventiona drip systems are minimized and repaced by simpe do-it-yoursef equipment ow-head drip irrigation technoogies. Low-head drip systems operate under pressures of m water head compared to the m water head needed for standard drip irrigation (Giead 1985). Sma reservoirs such as oi drums can be used as header water tanks. These are supported on bocks so that the water pressure fas within the required range. Perforated fexibe pastic piping conveys water to the pants. Low-head drip irrigation technoogies incudes gravity drip irrigation and bucket and drum kits. Gravity drip irrigation Gravity drip irrigation makes use of very ow pressures. It fits into the infrastructure of existing channes, ditches and gravity-irrigated fieds. Due to the ow pressures, the system is very sensitive to ground eevation differences and specia drip ateras operating under the above-mentioned condition are used (Giead 1985). The ow operating pressure has many advantages for the design of gravity drip irrigation. These incude: Enabes substantia enargement of the cross-section of the abyrinth fow passage of each emission unit, which simutaneousy wi minimize or even avoid cogging. Transating research into practica toos for farmers From science to smahoder Smahoders are those women and men farmers who use rainwater and sometimes irrigation water to grow crops on their own and, rented and, or common ground. The majority of farmers in deveoping countries are smahoders. Many of them have itte and and water and itte or no money or credit to manage, and they are not empowered to participate in management at viage or district eve. Smahoders often have no choice but to expoit their and and water resources in ways that ead to widespread and serious environmenta damage. Hundreds of miions of smahoders hardy benefit from past research on and and water management because they do not know about it, and because recommendations are too vague, toos are too impractica or soutions too expensive. Yet much reevant knowedge and expertise does aready exist. The chaenge before us is to bring practica knowedge and usefu toos from research to the minds and hands of sma farmers. Through IWMI s research on smahoder and and water management, we work for rura smahoders that farm soping ands, for those that have no choice but to farm od, infertie sois in the upand parts of river basins and for farmers who are trying to make ends meet in periurban areas. Water and nutrients from the soi are essentia to grow crops. Providing an adequate baance of these inputs maximizes the efficiency of investments in both. Our research goa is to produce more appropriate knowedge and better-adapted toos specificay for smahoders, to hep them achieve the optimum water/ nutrient baance consistenty and on a ong-term basis. Armed with these improvements, farmers can use their water and and resources more effectivey and get reasonabe returns on their investments. This increases their income and encourages investments in natura resources to make their use sustainabe. To achieve this goa of putting practica interpretations of our research into miions of smahoder farmers hands requires considerabe reach. We are doing this by buiding partnerships with Nationa Agricutura Research and Extension Services (NARES), whose task is to do exacty this. We are deveoping recommendations and toos with NARES, testing and improving them with the hep of farmers, and supporting NARES in their efforts to disseminate the resuts to smahoders and this synergy wi create the conditions that substantiay improve the we-being of many smahoders, and make use of natura resources sustainabe. Dr. Frits Penning de Vries, is the eader of IWMI s theme on sustainabe smahoder water and and management systems. 25

5 The drip rate can be reduced down to 1.2/h/m, despite the arge fow passage. Lower drip rate means arger atera ines and diameter reduction of the distribution and main ines and aso of the other contro eements. It enabes use of a atera produced from a very thin but sti very strong pastic fim made from a speciay taiored poymer, which heps to reduce gravity drip irrigation atera costs to a minimum. Optima growing conditions can be achieved because the very ow drip rate enabes round-the-cock irrigation at peak season. Advances in drip irrigation technoogy have made it possibe to deveop a simpe bucket/ drum kit system that ow-income famiies can afford (produced by Chapin Watermatics). For severa years, bucket kit drip irrigation has heped thousands of famiies provide fresh vegetabes for their famiies. It has proved especiay usefu in water-scarce areas where water has to be carried for ong distances requiring that every drop is used in the most efficient way possibe. Overview of drip kits and ines avaiabe in Kenya. Type of Suppier(s) Emitter Wa thickness Tape diameter Current cost system/tape spacing (cm) (mm) (mm) (Ksh. and US$) Chapin KARI, FPEAK per kit ($19) T-Tape 520 Booth per meter ($0.24) Typhoon 25 Amiran per meter ($0.32) Victoria ShadeNet Ltd per meter ($0.18) Waterboys KARI, for ,800 per kit ($56) demonstration In Kenya, this simpe technoogy is being promoted by KARI and the Fresh Produce Exporters Association of Kenya (FPEAK) in cooperation with Chapin Third Word Projects. The system is gaining popuarity and is being used by many famiies in the Edoret, Ngong, and Kajiado districts in the Rift Vaey province; Gatundu and Ndeiya-Karai in the Centra province; Tharaka, Machakos and Kitui in the Eastern province, and in many other drought- prone areas. In addition to Kenya, the bucket kit has aso been impemented in Zambia, Mozambique, Maawi, Swaziand, South Africa, Namibia, Uganda and Nigeria (Chapin 1998). Bucket and drum drip kits The bucket kit is a sma-scae drip irrigation system with high water use efficiency that operates at ow pressure heads of 0.5 to 2.0 m ( bar). It consists of a 20-iter 26

6 bucket or a 200-iter drum, drip tape, fiters, rubber washers, mae and femae adapters, two suppy tubes and barb fittings. A 0.75-inch screen fiter with a fow ranging from 0.9 to 2.5 m 3 /h is provided with the drip kit. The bucket is mounted on a stand, which hods it one meter above the ground. The drip ines are suppied in engths of 15 m, and, for best resuts, they are aid on eve ground. If the drip ines go up a sma sope, the bucket or drum shoud be paced on the highest side. The ines are aid with the emitters facing up to reduce the probem of sediment setting on the emitters. In the case of the drum system, the drum is connected to a manifod with five openings, each ocated to cover a bed. The manifod incudes a PVC pipe, bends, gate vave, tees, and gue for fitting. Comparison of the avaiabe drip ines in Kenya There are many suppiers of different commercia drip systems in Kenya. The majority of existing drip ines are designed for high-pressure systems. There are few specificay designed ow-head drip ines. These incude Chapin, T-Tape and Waterboys. IWMI research evauated these, and the most commony avaiabe high-head drip ines for use with owhead systems. Two common probems experienced by farmers using ow-head drip systems are uneven water distribution, especiay on soping and, which can drasticay affect yieds due to under-irrigation of some pants and over-irrigation of others; and the tendency of emitters to cog. IWMI research tested existing ow-head drip irrigation systems in an effort to overcome or at east minimize some of these constraints. 27

7 Recommendations for farmers using ow-head drip systems Readiy avaiabe high-head drip ines can be adapted for use with ow-head systems. In addition to Chapin system drip ines, the existing high-head drip tapes, e.g., Typhoon, T-Tape and Victoria, can be used for ow-head (as ow as 0.5m) bucket kit systems without substantiay affecting performance (water distribution uniformity aong the drip tape for various suppy head, atera ength and and sope). This means ow-head drip kits can be assembed ocay with readiy avaiabe high-head drip tapes and fittings. Land sope has more effect on water distribution uniformity than either head or atera ength. Different drip tapes perform differenty with respect to the three parameters evauated and sope, atera ength, and water suppy head. Thus discharge rates vary with head, sope, atera ength and type of drip tape. Water distribution uniformity decreases with the atera ength, though different tapes perform differenty, e.g., for T-Tape, ength increases beyond 20 m have no significant effect on water distribution uniformity. Athough water suppy head seems to have no significant effect on water distribution uniformity, there is a sight improvement with increase in head, especiay for high-head-designed tapes. The effect of head is significant for soping and. However, and sope has more effect on water distribution uniformity than either head or atera ength. The effect of and sope on water distribution for Victoria driptape. To adapt to the performance variation between the two drip ines of a kit, farmers shoud grow crops with higher water demand on the side of the higher performing ine. Water distribution varies between the two drip ines of the bucket kit. The difference in performance coud be attributed to either one ine being a bit ower than the other, more eakage on one ine or more cogging on one ine. These factors coud ead to pressure differences and hence the variations in water distribution. Farmers can adapt to this difference by growing the crops with higher water demands on one side. 28

8 For soping and, the bucket shoud be paced up-sope; the crops with the highest water demand shoud be panted down-sope. Water distribution uniformity decreases with an increase in and sopes, whether up-sope or down-sope, but down-sope drip kit ayout gives a better water distribution uniformity than up-sope ayouts. If and is soping, as is normay the case, it is advisabe to pace the bucket on the higher side, i.e., down-sope. For soping and, high water-consumption crops shoud be panted on the downstream side whie ess water-consuming crops shoud be panted upstream. Impications of combining any two parameters. The combined effect of any two parameters: water-suppy head and and sope, water suppy-head and atera ength, and and sope and atera ength reveaed that: It is not advisabe to use onger engths (beyond 7.5 m) for soping and. It is advisabe to use higher head (1.50 m) for onger atera engths. Water uniformity distribution improves significanty with increase in suppy head for soping and, especiay for up-sope ayout. Up-sope ayout is recommended with high water suppy head. Fiters can be improv ised out of common househod materias to prevent emitter cogging. To improve water distribution uniformity, a fiter which is an important component of the drip kit, is used to prevent emitter cogging. Waterboys, which have no fiter, seem to be prone to cogging. Locay avaiabe fiter materia, e.g., used ady s stockings, mosquito nets, etc., can be improvised as a form of jua kai fiter. REFERENCES Chapin, R. D Bucket kit news. Giead, G. G Gravity Drip Irrigation (GDI) System. Proceedings of the Third Internationa Drip/Tricke Irrigation Congress. Caifornia, U.S.A. ASAE Vo. II. KARI Simpe drip irrigation makes a big difference on sma farms. Harambee-puing together for Kenya. A report of the Kenya Nationa Research Project. KARI, Nairobi. Lusaka, N Bucket kits in Kenya. Bucket Kit News, Chapin Living Waters Foundation. Unpubished report. Ndiritu, C Quoted from Chapin Living Waters Foundation Brochure. Ouko, B Kenya Isands Mission Drip Irrigation Programme. Proceedings of Workshop on Sma-Scae Drip Irrigation Experience Sharing Workshop September, 1998, Kitui Kenya. Reaves, R.E Third word faith in action. Irrigation Journa 45(6). Adams Trade Press. Winrock Proceedings of Low-Head Drip Irrigation Review Workshop February, 2000, Nairobi, Kenya. S.N Ngigi, J.N. Thome, and D.W. Waweru are from the University of Nairobi s Department of Agricutura Engineering; H.G. Bank was IWMI s regiona representative in Eastern Africa up unti August This research is part of a series of projects and investigations by IWMI and its partners, examining various aspects of sma-scae and informa irrigation in southern and eastern Africa. The research was carried out with support from the African Deveopment Bank. 29