e r 2 - Umgeni Water

| Water Resources Chapterconstructing Phase 1 of the Maphumulo Bulk Water Supply Scheme (BWSS) to supply the communities ofMaphumulo, Maqumbi and Ashville. This scheme will initially draw water directly from the Mvutshane River,which is a tributary of the Hlambitwa River, which in turn is a tributary of the Mvoti River. Phase 2 of this schemeentails the construction of a dam on the Mvutshane River to replace the run-of-river abstraction system. This willincrease the yield from the scheme and ensure a more sustainable supply. The detailed design of this dam iscurrently underway and construction is expected to commence in 2012. A possible later extension to this scheme isto augment the Mvutshane Dam from the Hlambitwa River.Upper Mvoti Bulk Water Supply Scheme: Mvoti-Poort DamIn the long-term the intention is to consolidate the various schemes in the area inland from the North Coast region(areas bounded by the uThukela and Mvoti rivers and extending from Greytown in the west to Maphumulo in theeast) ,as well as incorporate other communities that fall outside of the current supply areas. This can be achievedthrough the development of a regional bulk water supply scheme that is able to meet the potable water needs ofthe region on a long-term sustainable basis. This regional scheme will best be supported by a water resourcedevelopment on the upper Mvoti River. Investigations conducted by DWA in the past have shown that a smalldam at the previously identified Mvoti–Poort dam site would be a possible solution. Umgeni Water has thereforerequested DWA to undertake appropriate water resource investigations linked to developing a dam at the Mvoti-Poort site or at another suitable site in its vicinity. It is envisaged that the water resource development andtransfer infrastructure development investigations will proceed in a concurrent and integrated manner.Lower Mvoti Bulk Water Supply Scheme: Welverdient DamDWA and Umgeni Water conducted numerous water resource and supply infrastructure investigations of the lowerMvoti River catchment during the latter half of the 1990s. At the time, the proposed Isithundu Dam (serving bothirrigation and potable water demands) with a downstream abstraction works located near the town of KwaDukuzawas identified as being the preferred infrastructure development configuration. However, a number of criticalassumptions have since changed. Most significantly, legislative changes governing national raw water pricing hasled to the irrigation sector withdrawing from the proposed scheme on affordability grounds. The implication isthat storage options serving only the potable water sector now need to be considered.Umgeni Water has therefore requested DWA to urgently re-institute investigations to review the findings of theprevious investigations and develop detailed feasibility plans for the next phase of water resource augmentationfor the North Coast System – most likely to be the proposed Welverdient Dam option. Umgeni Water willundertake concurrent detailed feasibility level investigations into the associated bulk water transfer infrastructure.It is envisaged that both investigations will proceed simultaneously and in an integrated manner.7.4.3 South Coast System: Planned Developments and ShortfallsThe water resources that support the Middle South Coast area lack substantial storage capacity, making themespecially susceptible during periods of drought as witnessed during the latter part of 2010. While theinfrastructure linkages between the Umzinto, Mtwalume and Craigieburn water treatment works’ were able toalleviate localised supply shortages for short periods, they were not able to sustain supply over longer periods andwater restrictions were often required.Several localised solutions were investigated, including an assessment by DWA of the feasibility of a low-level weiron the Mtwalume River to improve abstractions at this point during low flow periods. These minor water resourcedevelopments only solve the problem in the short-term. As with the North Coast area, the Middle South Coastarea is experiencing strong growth in water demand, driven by economic growth in the region, and it is envisagedthat a major water resource development and/or inter-basin transfers will be required to provide a long-termsolution to water scarcity in the area.Umgeni Water Five-Year Business Plan | 2011/2012 to 2015/2016 Page 37