South Africa From: The Orange–Senqu River BasinInfrastructure Catalogue,ORASECOM Report 001/2013 Physical informa became greatly reduced andarable landhadtobede-scheduledprior toconstruction tunnel. ofthe Nelson Mandelaetropole) tworiverbasins ofdamsinthese capacities the andindustrialuse.Duetosiltation, Grahamstown urban(including Cape forirrigation, The Eastern watertothe and tunnelistodivert purposeofthe Purpose Sundays rivers. The tunnel has a length of 82.8 km, a diameter of 5.35 m and a maximum capacity of 54 m TeebusGariep Damtothe Great Spruitandthe Brak River, andfrom there Great ofthe valleys tothe F Orange–F network ofcanals,weirsandbalancingdams.This restored ofhectares andenabledthousands The ofirrigation. reservoirs, of the andsiltation by salinisation Orange– the F andexacerbatedDue tosevere duetowatershortages, formany years,partly stress Cape underwent Eastern the Description upperreachesin the Great ofthe F The Orange–F Loca An intake lake towerinthe some 20 km from tunnelthrough GariepDamheads the Suurberg the plateau. Orange–Fish Transfer Tunnel tion Canal name ish Transfer Tunnel was completed in 1975 and is the key structure by which water is delivered from the Orange–Fish TransferTunnel Orange RiverProjec ish Transfer Tunnel runsfrom Orange GariepDamonthe RivertoGrassridge Damwhichislocated tion astern CapeP Eastern ish Riverinthe Length (km) 83 t ish Transfer Tunnel wasconstructed, a with together Capacity (m rovince. 54 3 /s) ish andthe 3 /s. Orange–Fish TransferTunnel

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