Service Contract No 2007 / 147-446 NYANYALI ... - Swaziland

9 C O N C L U S I O NPump StationNyanyali’s ETA 80-250 pump is driven by a 55 kW 2-Pole motor designed to handle the 43hectares under sugarcane. There is no intake structure instead the foot valve is suspended atthe bank of the Mkhondvo River. The foot valve is not protected in any way and isintermittently in direct contact with the bottom of the channel and debris carried with the riverwater. Sand bangs are used to redirect the receding river water back into the sump,especially when the river level drops. The sump has no provision for cleaning, in order toclean this sump one has to swim in the crocodile infested river.The 55kW motor that drives this pump is correctly specified. These results will only beconclusive after accurately determining system pressure requirement. There is a possibilitythat the 80m indicated on the pump information plate is too correcting this could result inusing a smaller motor.The evaluation of pumps could not identify whether the pumps are optimally operating or notbecause the pump was not in operation during the evaluation. The assessment was carriedout after a period of heavy rains which not only raised the river level but also conceded a lotof iron oxide. According to Nyanyali management irrigating during this time causes thismaterial to accumulate inside the pipelines and in the long run reduces their capacity. Pumpperformance is, also, seriously affected when operated during the time, more so, because theiron oxide changes the specific gravity of the water. This evaluation, in any case could nothave been conclusive because there is no flow meter to measure pump discharge.This FA will require at least E95 000.00 to attend to immediate and short termrecommendations which include getting all pumps running to full capacity, replacing allincorrectly dimensioned fittings (bends and reducers) on the suction and delivery manifoldwith the correct size, etc. an intake sump will have to be constructed at a cost of E150000.00.Main Distribution LineNo information was available on irrigation layout and pipe sizes and class and an undisputedconclusion on whether the supply system was correctly designed or not cannot be drawn untildetails on pipe size, pipe classes, and distances occupied by the different sizes are obtained.Nyanyali Farmers Cooperative Report - 2009 Page - 41 -