Coast once again looks to desalination plant

A DESALINATION plant for the central coast is still on the cards to meet future water needs, says a senior NamWater official.

Gert van Eeden, Manager Operations: Central at NamWater, told The Namibian that a desalination plant would definitely be needed at the current rate of development at the coast. Concerns over the long-term supply of fresh water to the central Namib area were again raised at recent public meetings on a new proposed uranium mine in the Namib Desert.The developer of Langer Heinrich Uranium, John Borshoff of Paladin Resources in Australia, said at the meetings that NamWater had indicated there was sufficient water to supply 1 million cubic metres a year to the mine.Van Eeden confirmed that there is enough water until 2018, even if the mine continued for longer than its minimum 10 years of operation.He also does not foresee a problem should other big developments, such as an oil refinery and smelter, come into operation at the coast.”There are still options in the Kuiseb and Omaruru rivers we have not yet developed to add to the current water supply,” said Van Eeden.A third option would be to start desalination.”Desalination will come one day,” he said.André Bruemmer, Manager:Water, Waste and Environmental Management at the Walvis Bay Municipality, said developers could not be chased away from the coast because of water.”If need be, desalination would have to start earlier.We simply cannot refuse development.”He felt the new mine was “not a train smash” in terms of water usage, as its annual consumption would be about a third of the Roessing mine’s annual usage and less than the fishing industry’s.”There is no doubt that over the long-term desalination would have to be developed.”Bruemmer said residents would not shoulder the full burden, as big developers would be asked to contribute.NamWater’s Van Eeden confirmed that each consumer would have to contribute to desalination.He added that new technology was bringing down the cost of desalination.”Should a new and cheaper technology become available in the near future, it would easily become an option to implement it sooner than planned.”Van Eeden explained that a forum of coastal belt water consumers, which included the municipalities, met on a quarterly basis to determine water needs.The local authorities also work on five-year projections in terms of water needs.”This makes water provision a moving target as we adapt it to the needs of consumers.”Apart from desalination, Van Eeden said the artificial recharge system at the Omdel Dam could still be expanded, while further boreholes in the Kuiseb River could be sunk as additional water sources.The Omdel scheme and Lower Kuiseb Aquifers are the two main water sources for the central coastal area.Figures released by NamWater last year indicated that an annual sustainable yield of 12,9 million cubic metres was available from the two main sources, while actual usage is around 11 million cubic metres.The sustainable yield is the volume of water that can be safely abstracted without causing any lasting damage to the aquifer or underground water source.Plans by NamWater to build a desalination plant were shelved in 2002 when good inflow of water into the Kuiseb aquifer during two flood events in 1997 and 2000 sufficiently recharged the system.Consumption also decreased sharply when water prices increased in anticipation of desalination.At Walvis Bay, the pilchard canning industry produced much less because of small fishing quotas.General consumption at the harbour town has also stabilised over the last four to five years, despite many new connections.This is attributed to a new tariff structure implemented for residents, as well as the provision of purified effluent for use in gardens.The Roessing mine has also cut back considerably on its usage since 1999.The Walvis Bay Mayor, King Mandume Muatunga, sounded a warning at a recent water saving competition for schools, though.He said water awareness should never be a one-off event.”Protecting our scarce and finite water resources forms an integral part of sustainable development.”Concerns over the long-term supply of fresh water to the central Namib area were again raised at recent public meetings on a new proposed uranium mine in the Namib Desert.The developer of Langer Heinrich Uranium, John Borshoff of Paladin Resources in Australia, said at the meetings that NamWater had indicated there was sufficient water to supply 1 million cubic metres a year to the mine.Van Eeden confirmed that there is enough water until 2018, even if the mine continued for longer than its minimum 10 years of operation.He also does not foresee a problem should other big developments, such as an oil refinery and smelter, come into operation at the coast.”There are still options in the Kuiseb and Omaruru rivers we have not yet developed to add to the current water supply,” said Van Eeden.A third option would be to start desalination.”Desalination will come one day,” he said.André Bruemmer, Manager:Water, Waste and Environmental Management at the Walvis Bay Municipality, said developers could not be chased away from the coast because of water.”If need be, desalination would have to start earlier.We simply cannot refuse development.”He felt the new mine was “not a train smash” in terms of water usage, as its annual consumption would be about a third of the Roessing mine’s annual usage and less than the fishing industry’s.”There is no doubt that over the long-term desalination would have to be developed.”Bruemmer said residents would not shoulder the full burden, as big developers would be asked to contribute.NamWater’s Van Eeden confirmed that each consumer would have to contribute to desalination.He added that new technology was bringing down the cost of desalination.”Should a new and cheaper technology become available in the near future, it would easily become an option to implement it sooner than planned.”Van Eeden explained that a forum of coastal belt water consumers, which included the municipalities, met on a quarterly basis to determine water needs.The local authorities also work on five-year projections in terms of water needs.”This makes water provision a moving target as we adapt it to the needs of consumers.”Apart from desalination, Van Eeden said the artificial recharge system at the Omdel Dam could still be expanded, while further boreholes in the Kuiseb River could be sunk as additional water sources.The Omdel scheme and Lower Kuiseb Aquifers are the two main water sources for the central coastal area.Figures released by NamWater last year indicated that an annual sustainable yield of 12,9 million cubic metres was available from the two main sources, while actual usage is around 11 million cubic metres.The sustainable yield is the volume of water that can be safely abstracted without causing any lasting damage to the aquifer or underground water source.Plans by NamWater to build a desalination plant were shelved in 2002 when good inflow of water into the Kuiseb aquifer during two flood events in 1997 and 2000 sufficiently recharged the system.Consumption also decreased sharply when water prices increased in anticipation of desalination.At Walvis Bay, the pilchard canning industry produced much less because of small fishing quotas.General consumption at the harbour town has also stabilised over the last four to five years, despite many new connections.This is attributed to a new tariff structure implemented for residents, as well as the provision of purified effluent for use in gardens.The Roessing mine has also cut back considerably on its usage since 1999.The Walvis Bay Mayor, King Mandume Muatunga, sounded a warning at a recent water saving competition for schools, though.He said water awareness should never be a one-off event.”Protecting our scarce and finite water resources forms an integral part of sustainable development.”