Famers and rural communities obtain irrigation and drinking waters, some of the priority needs of humans, through open wells, ponds and streams. Inefficient supply of such waters contributes to a decrease in agricultural production and most of the diseases that afflict the people in rural areas. Water lifting device, like the 'Tapak-tapak' pump, can best answer some of the small-scale irrigation and rural water supply problems. This is because it is easy to construct, the materials are locally available, easy to dismantle and reassemble, easy to carry around, less expensive and could be handled by both women and children. The pump with a slight modification on the suction pipe (made 'gradual' insteadof 'sharp' bend) of the original design was constructed and tested. The performance of the pump was evaluated by making it lift water from a pond of 0.55m deep, low static head (LSH) and 3.10m deep, high static head (HSH), and a pipe length of 0.95m and 3.50m, respectively. Two types of up and down movements of the legs - fast (FS) and slow (SS) speeds at each static head were used. At trie LSI I, the mean FS and SS were 41 and 33 cycles/min. while at the HSH, the mean FS and SS were 42 and 35 cycles/min, respectively. The mean discharge at the LSH with FS was 125.2 1/min. and LHS with SS was 83.7 1/min. The values at the HSH with FS and HSH with SS were 106.8 1/min. and 69.2 l/min respectively. At the HSH the friction losses in the pipe were 5.86 cm and 2.51 cm for the FS and LS, respectively. Thecorresponding friction losses at the LSH were 2.19 cm and 1.08 cm. The hydraulic efficiency ranged between 92 percent and 98.9 percent depending on the speed and value of the static head. The lower the speed, the higher the hydraulic efficiency, and thehigher the static head, the higher the hydraulic efficiency. The volumetric efficiency
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