Windhoek — The decision on how to harvest water from the huge aquifer discovered in the northern part of the country, could take as long as six years.

This is because there is still a lot of technical work outstanding to determine whether the aquifer, discovered some 300 metres beneath a part of northern Namibia, is economically viable to pursue.

"A lot of work has still to be done. [We] do not know the extent of the aquifer, maybe it is extending to Angola. We might come up with big plans, while there is no water, or not plan well, while there is a lot of water," Under Secretary in the Department of Water Affairs and Forestry, Abraham Nehemia, said at a media briefing on Monday this week. Technical work could take as long as six years to complete, he said.

The underground aquifer was recently discovered, which scientists have named Ohangwena II.

The aquifer is estimated to be large enough to supply the northern regions of the country with fresh water for the next 400 years. Scientists have dated the water body to be as old 10 000 years, but with cleaner water for drinking than many modern sources.

However, there are concerns that unauthorised drilling could threaten the new supply.

An aquifer is a body of saturated rock through which water can easily move. It is both permeable and porous and includes such rock types as sandstone, conglomerate, fractured limestone and unconsolidated sand and gravel.

Sources and quantities of water in northern Namibia are variable, with either too much of it or too little, depending on the area.