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Applications www.worldpumps.com Succumbing to e ects from climate changeWater & wastewatersupplies water in bulk to industries and municipalities.Installation, repairs or replacement of the pumps that pump water in all the municipalities is the responsibility of NamWater. NamWaters Corporate Commu- ce said in a statement during the November/December crisis that the public water utility was still exploring the possibility of another round of repair of the pumps to restore water supply in Katima Mulilo, a town of an estimated 26,000 people.inking the e ects of climate change to the performance or breakdown of a water pumping solution may look a farfetched idea for some. But that is what has rendered a small town in the Southern Africa country of Namibia a water stressed spot for more than three years.The climax of the water shortage crisis in Katima Mulilo Town Council in Namibias Caprivi region hit a crescendo between November and December of 2011 when two water pumps, installed at Africas fourth longest river, the Zambezi, failed.The vertical multistage in-line centrifugal pumps that pump water from the river, which passes through the countries of Angola along Namibia, Botswana and Zimbabwe to Mozambique into the Indian Ocean, had been repaired before they failed beyond repairŽ according to the Katima Mulilo Town Councils acting chief executive cer Charles Nawa.Katima Mulilo, just like other local councils in Namibia, gets all its water supplies from the Namibia Water Corporation Ltd. (NamWater), a government controlled water utility that The climax of the water shortage crisis in Katima Mulilo Town Council in Namibias Caprivi region hit a crescendo when two water pumps, installed at Africas fourth longest river, the Zambezi, failed. Both the town and government are looking for a solution. Could a vertical multistage in-line centrifugal pump in a situation where water levels cannot be regulated and there is a possibility of the pump pulling in destructive materials from a water source be the answer? Food outlets, like this “ sh eatery in Katima Mulilo town, are the worst hit by the perennial water shortages caused by unreliability of water pumps at the Zambezi River. WOPU1212_App_Katima 1613-11-2012 14:10:42 Applications www.worldpumps.com A recent climate change forum held in South Africas city of Cape Town warned of even worse devastation on water sources and towers should governments in the region fail to take measures to reduce both carbon emissions and the style of environmental Changes in water levelAfter the Zambezi River water levels dropped, there was reduction in pressure from the intake point forcing the pumps to pull in unwanted material from the river. The water level in the river is low, so the pump is pulling in all sorts of materials which are damaging the pump mechanically,Ž Erdtelt said.The fall in the water level would have resulted in reduced weight of the water above the pumps inlets hence leaving the atmosphere as the only force to push down the water into the pump.NamWater said water from the Zambezi River is pumped directly to the “ ve pressure sand “ lters at a reservoir where any suspended matter is removed from the water. The water is then disinfected by adding a chlorine gas/water mixture as it ” ows from the “ lters to an underground reservoir."From the reservoir the water is pumped to supply Katima and its suburbs, Mafuta, the army base at Mpacha and Chinchimane-Linyanti pipeline. Chlorine disinfection again takes place before the water is pumped to the consumers," Namwater explains.NamWater further said the raw-water entering the Katima Mulilo water treatment plant is already fairly clean, and the plant (Katima Mulilo) employs only two treatment steps … “ ltration and disinfection. Adding of ” occulants and settling of suspended parti-cles is thus not necessary on this plant.ŽThis process has been disrupted on several occasions because of the frequent reduction in water volumes at the Zambezi River and the resulting water pumping complications.How effective and suitable is a vertical multistage in-line centrifugal pump in a situation where water levels cannot be regulated and there is a possibility of the pump pulling in destructive materials from a water source?Although both NamWater and Katima Mulilo Town Council could not respond to queries on the suitability of this type of pump in the prevailing situation at the Zambezi River, various manufacturers attest to the fact that properly installed, and all parameters remaining correct (including average water levels at a water source like a river,) the water pump segment.According to Feeling Pumps (Shanghai), a maker of vertical multi-stage in line pumps, but which has no connection with the supply and installation of the failed water pumps at Katima Mulilo, this water pumping solution is preferred by many water supply service providers across the globe. This is because of its small volume, lightweight, low noise and easy maintenance. Those who have chosen this kind of pump have been attracted to it by its vertical and The company said the two water pumps complement each other but at times, like it happened during the water shortage period, both pumping solutions can be faulty plunging the town and its environs into a water supply crisis.NamWater blamed an electrical fault and failure of the internal parts of the pumps on their break down. "We have two pumps and we use one water pump at a time. It was unfortunate that when we switched to the other, it also had a problem," NamWater said in a statement.NamWater spokesperson Tommy Numbala said the public water utility was also consid-ering importing new water pumps as a long term solution to the perennial breakdown of the two solutions already installed. However, by late April 2012, the procurement process was yet to kick o in earnest.It is after the tendering process has been kick-started that it would be possible to know where the pumps will be imported from and who will do the installation. NamWater has in the past relied on its own engineers for the installation and maintenance of the water pumps at all its pumping sites.Back to the climate change and perform-ance of these two pumps. Michael Erdtelt , a technical engineer at Katima Mulilo Town Council, said the damage caused to the pumps arose from the falling water levels of Zambezi River. The drop in the rivers water level is a common phenomenon in Southern Africa where ravages of drought have ected even the largest water bodies in the region.The ” uctuating water levels at the mighty Zambezi River have lead to low pressure and the subsequent pulling in of material impurities by the pumps which have been blamed for their malfunctioning. WOPU1212_App_Katima 1713-11-2012 14:10:44 Applications www.worldpumps.com compact structure, Feeling said. Its inlet and outlet flanges are located at the same central line, small area occupation and installation.Ž|Its assembly mechanical seal makes its installa-tion and maintenance safer and more conven-ient, and guarantees the reliability of the mechanical seal, the Shangai-based pump maker said on its website. Long term ideasA long-term solution to the water crisis in Katima Mulilo, which residents say has been recurring over the past three years, lies in improving the towns water supply network in addition to installing a new water pump.Although there is currently an ongoing programme to upgrade the water supply systems at Katima Mulilo, there have been proposals for more and bigger water reser-voirs that can outlast the prolonged drought periods experienced in the region.The planned upgrade of water systems in Katima Mulilo follows completion of feasi-bility study by Lund Consulting Engineers (LCE), experts in water, civil and structural engineering as well as project managers.LCE said the project study commissioned by the Department of Water Affairs in the Ministry of Agriculture, Water A airs and Forestry, entailed a physical assessment of the water supply infrastructure (mostly single borehole installations) between Katima Mulilo and Kongola in the Caprivi Region and the preparation of proposals and cost esti-mates for an upgraded water supply infra-structure to this area.ŽSeveral water supply options have been explored including upgraded boreholes to tap the currently used shallow aquifer, new bore-holes to tap the deep aquifer recently discov-ered, and the combination of a supply of piped water from Katima Mulilo (from the Zambezi River) and from the Kwando River near Kongola. The options are being explored in search of a long term solution to water shortages in the area.The Namibian government has allocated $4.2 million for the Katima water supply upgrading project spread over four years since 2009. The upgrading and expansion is likely to create additional water storage capacities and drawing points to cater for lean periods when the Zambezi Rivers ” ow is low or when the water pumping system fails.A number of institutions in Katima Mulilo have ered the brunt of the perennial water pumping disruption over the past two years with some reporting reduced business and disruption of operations as the crisis persisted.Residents have also been forced to draw water directly from the Zambezi River, a practice which has exposed them to water-borne diseases like cholera and the frequent crocodile attacks.At the height of any water shortage crisis in Katima Mulilo, food outlets are among the most ected businesses while most public toilets in the town were shut for lack of water. Residents had to walk several kilometers to fetch water from Zambezi River for cleaning and ” ushing toilets.The other large rivers relied on by Namibia for water including Orange River in the South as well as the Okavango Rivers in the North.However, the residents are not only paying the price of a malfunctioning water pumping system, they have also to pay for the cost of abstracting water from the Zambezi River. This has been considered one of the most prohibi-tive factors in expanding water supply to the nearest local councils including Katima Mulilo. Local councils, including Katima Mulilo, use more than 70 million m3 of water out of the estimated 300 million m3 consumed in Namibia. Namibia tops sub Saharan African countries in providing water through municipal councils. The councils buy the water from NamWater for distribution to consumers. The country, which is the fourth-largest exporter of nonfuel minerals in Africa and the world's “ fth-largest producer of uranium, spends an average of 3% of its gross domestic product in the operations of water utilities, the largest amount in sub Saharan Africa.Despite the hiccups in water supply in Katima Mulilo, the UN listed Namibia as one of the leading sub Saharan countries to have improved its water supply situation. Last year, the UN did an evaluation of Namibia's water supply and commended access levels compared to the situation at independence in 1990."A large part of the population cannot, however, make use of these resources due to the prohibi-tively high consumption cost and the long distance between residences and water points in rural areas," another report on the country's water and sanitation said. www.namwater.comThe Namibia Water Corporation Ltd (NamWater) looks forward to import centrifugal pumps, similar to this one by Yongjia Haihe Pumps Factory China, to alleviate water shortages in Katima Mulilo town. (PHOTOS COURTESY: Ministry of Information and Communication Technology and Yongjia Haihe Pumps China.) WOPU1212_App_Katima 1813-11-2012 14:10:47